JP2014052948A - High speed chaos optical signal generation optical circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate random numbers with high disorder that is capable of simplifying an entire system, and can cope with a request for generating a high-speed random number.SOLUTION: A high-speed chaos optical signal generation optical circuit is configured to: demultiplex, by an optical demultiplexer SP-1, clock signal light to be output from a light output port P-MZ-1-cross of a Mach-Zehnder interference type light intensity modulation part MZ-1 into two systems; input the clock signal light of two systems to phase modulators R1 and L1 provided in two interference arms in the Mach-Zehnder interference type light intensity modulation part MZ-1 as clock signal light for controlling a phase modulation; and thereby generate a phase difference in clock signal light to be input from a light input port P-MZ-1-1 and propagating in the two interference arms. The phase modulators R1 and L1 sufficiently eliminate the clock signal light for controlling the phase modulation, and selectively output only the clock signal light obtained by modulating the phase. Further, the phase modulators R1 and L1 have a light reception part provided on one port not led outside, of two light output ports.

Description

  The present invention generates a random number used in a computer that performs calculations such as device modeling, financial derivative calculation, and weather simulation, a random number used in a secret key sharing cryptographic system, or a random number used in quantum cryptography communication. The present invention relates to a high-speed chaotic optical signal generating optical circuit.

  Conventionally, as a method for generating a random number, roughly three methods have been proposed. The first random number generation method generates random numbers by calculation based on a random number generation program. The second random number generation method generates a random number based on physical noise inherent in an electronic circuit.

  According to the third random number generation method, (1) a chaos laser (see Non-Patent Document 1) or (2) laser light is used according to the output power of a predetermined time using an E / O (Electrical / Optical) modulator. An optical chaos signal source (see Patent Document 1) having an O / E (Optical / Electrical) conversion delay feedback electric circuit that modulates the intensity and (3) the optical path length difference between the two interference arms is controlled by the thermo-optic effect. A device that uses a plurality of Mach-Zehnder interferometers controlled so as to have a certain relationship in the optical path length difference, and realizes a chaos mapping relationship with the output power from each Mach-Zehnder interferometer (see Patent Document 2) ) Or the like to generate a random number based on the output chaotic signal.

  The first and second random number generation methods described above have a generation speed limit based on the operating frequency of a practical electronic device (see Non-Patent Document 2), and are sufficiently compatible with high-speed signal generation exceeding 10 Gb / s. I can't.

  In the random number generation by the chaotic laser disclosed in Non-Patent Document 1, it has been reported that the random number generation can be performed at a very high speed, but reproducibility should be ensured due to the complexity of the chaotic laser system. In addition, since the system configuration includes an optical fiber portion and the like, it is difficult to integrate and downsize the entire system.

  In addition, the random number generated by the chaotic laser is a signal generated based on the periodicity resulting from the use of an optical resonator or a well-known chaos generation mechanism, so that the output signal light has chaotic properties. Although recognized, it is imperfect in terms of randomness and does not mean a “random” signal similar to thermal noise.

  For this reason, in the example of Non-Patent Document 1, first, two chaotic output optical signals are prepared, and XOR logic operation processing is performed after 1-bit AD conversion is performed on the two chaotic output optical signals. It is necessary to improve the randomness of the signal by post-processing such as logic operation. For this reason, it is inevitable that the system becomes complicated and large including a post-processing logic operation unit.

Even in the random number generation by the optical chaotic signal source disclosed in Patent Document 1, it is difficult to integrate the entire system because a system configuration including an optical fiber unit and a high-frequency electric amplifier is required.
In the optical chaos random number generator disclosed in Patent Document 2, there is a limit of random number generation speed based on the control speed (several ms) based on the thermo-optic effect, and in addition, a temperature control unit, a digital data processing unit, a storage device, etc. Therefore, there is a problem that it is difficult to integrate the entire apparatus.

Japanese Patent No. 2960406 Japanese Patent No. 3396883

A. Uchida, et al., “Fast physical random bit generation with chaotic semiconductor lasers”, Nature Photonics, vol.2, p.728-732, 2008 "Efforts of Switch Optical Technology Entering Tbit / sec", Nikkei Electronics, No.719, p.107-113, 1998.6.29

As described above, the first and second random number generation methods have a problem that they cannot cope with high-speed signal generation exceeding 10 Gb / s.
In the random number generation method using a chaotic laser disclosed in Non-Patent Document 1, it is difficult to integrate and downsize the system, and there is a problem that the system becomes complicated in order to increase the randomness of the signal.

The random number generation method using an optical chaos signal source disclosed in Patent Document 1 has a problem that it is difficult to integrate and downsize the system.
The optical chaos random number generator disclosed in Patent Document 2 has a problem that it is difficult to deal with high-speed signal generation, and in addition, it is difficult to integrate the entire system.

  The purpose of the present invention is to generate random numbers used in calculators that perform calculations such as device modeling, financial derivative calculations, weather simulations, random numbers used in secret key sharing cryptosystems, or random numbers used in quantum cryptography communications. The high-speed chaos optical signal generation optical circuit for this purpose is capable of simplifying and integrating the entire system and responding to requests for ultra-high-speed optical random number generation utilizing the characteristics of the optical chaos method suitable for high-speed operation. It is an object of the present invention to provide a high-speed chaotic optical signal generation optical circuit that can generate random numbers with high randomness.

  The high-speed chaotic optical signal generation optical circuit (first embodiment) of the present invention includes a first Mach-Zehnder interference type optical intensity modulation means MZ-1 that inputs an RZ-type clock signal light, and the first Mach-Zehnder. RZ type clock signal light output from one of the two optical output ports P-MZ-1-cross and P-MZ-1-bar of the interference type optical intensity modulation means MZ-1 is divided into two systems. The first optical demultiplexing means SP-1 for wave generation and the two systems of RZ type clock signal light demultiplexed by the first optical demultiplexing means SP-1 are used as the clock signal light for phase modulation control. 1 Mach-Zehnder interference type light intensity modulation means MZ-1 and a first optical waveguide guided to the first phase modulation means in the Mach-Zehnder interference type light intensity modulation means MZ-1, Light that receives the RZ type clock signal light Force port P-MZ-1-1, two first interference arms that transmit the RZ-type clock signal light input to this optical input port P-MZ-1-1, and the two first interferences One of the two optical output ports P-MZ-1-cross and P-MZ-1-bar provided at the end of the arm and one of the two first interference arms are provided. The RZ type clock signal light transmitted by the interference arm is composed of the first phase modulation means R1 and L1 for phase modulating the RZ type clock signal light according to the light intensity of the RZ type clock signal light inputted from the first optical waveguide. The first phase modulation means R1 and L1 respectively combine the clock signal light transmitted by the first interference arm and the clock signal light for phase modulation control, and combine the signal light. The first light that splits The first optical waveguide arm that transmits the two types of signal light outputted from the first optical interference type optical branching unit, and the two first optical waveguide arms. A second optical interference type multiplexing / branching unit that multiplexes the two signal lights and demultiplexes the combined signal lights into two systems, and one each for the two first optical waveguide arms. , First optical phase modulation control means for phase-modulating the clock signal light transmitted by the first interference arm in accordance with the light intensity of the clock signal light for phase modulation control, and the two first optical lights A first phase adjusting means provided on at least one of the waveguide arms and capable of adjusting the phase of the signal light in accordance with the amount of injection current supplied from the outside; and the second optical interference type combination. Of the two optical output ports of the branching means, the first interference arm And a first light receiving means for receiving signal light output from the one not connected to the first optical waveguide, further provided in the first optical waveguide, and separated by the first optical demultiplexing means SP-1. A delay corresponding to a difference in optical propagation delay until the two RZ-type clock signal lights that have been waved reach the first phase modulation means R1 and L1 is input to the first phase modulation means R1 and L1. The first optical propagation delay difference imparted to the RZ clock signal light having the longer light propagation delay until reaching the first phase modulation means R1 and L1 among the two RZ clock signal lights. Means D-D-1, and one of the two light output ports of the second optical interference type branching means provided in each of the first phase modulation means R1 and L1, and the first light receiving means The phase-modulated clock signal light is output from the unconnected one The output signal light is obtained from one of the two optical output ports P-MZ-1-cross and P-MZ-1-bar of the first Mach-Zehnder interference type optical intensity modulation means MZ-1. It is characterized by this.

  Further, one configuration example (second embodiment) of the high-speed chaotic optical signal generation optical circuit of the present invention is further provided in the first optical waveguide, and the first optical demultiplexing means SP-1 Optical delay means DT-1 for providing a predetermined delay to each of the two RZ-type clock signal lights that have been demultiplexed is provided.

  Further, one configuration example (third embodiment) of the high-speed chaotic optical signal generating optical circuit according to the present invention further includes second Mach-Zehnder interference type optical intensity modulation means MZ- that inputs the RZ type clock signal light. 2 and RZ output from one of the two optical output ports P-MZ-2-cross and P-MZ-2-bar of the second Mach-Zehnder interference type light intensity modulation means MZ-2 Optical output ports P-MZ- of the second optical demultiplexing means SP-2-1 for demultiplexing the type clock signal light into two systems and the second Mach-Zehnder interference type optical intensity modulation means MZ-2 Among the 2-cross, P-MZ-2-bar, RZ type clock signal light output from the one not connected to the second optical demultiplexing means SP-2-1 is demultiplexed into two systems. 3 optical demultiplexing means SP-2-2 and the second light The two RZ-type clock signal lights demultiplexed by the wave means SP-2-1 are used as the phase modulation control clock signal lights in the second Mach-Zehnder interference type light intensity modulation means MZ-2. The second optical waveguide guided to the phase modulation means and the two systems of RZ type clock signal light demultiplexed by the third optical demultiplexing means SP-2-2 are used as the clock signal light for phase modulation control. The first Mach-Zehnder interference type light intensity modulation means MZ-1 and a third optical waveguide leading to the third phase modulation means in the first Mach-Zehnder interference type light intensity modulation means MZ-1, Further, instead of the first phase modulation means R1, L1, one RZ type clock signal light provided on each of the two first interference arms and transmitted by the first interference arm, Input from the first optical waveguide The first phase modulation means R1-1 and L1-1 that perform phase modulation according to the light intensity of the Z-type clock signal light, and the two phases behind the first phase modulation means R1-1 and L1-1. One RZ type clock signal light is provided for each first interference arm and transmitted by the first interference arm according to the light intensity of the RZ type clock signal light input from the third optical waveguide. The second phase modulation means R1-2 and L1-2 for phase modulation, and the second Mach-Zehnder interference type light intensity modulation means MZ-2 receives the RZ type clock signal light. -MZ-2-1, two second interference arms that transmit the RZ-type clock signal light input to the optical input port P-MZ-2-1, and ends of the two second interference arms The two optical output ports P− provided in the section MZ-2-cross, P-MZ-2-bar, and one RZ type clock signal light provided by each of the two second interference arms and transmitted by the second interference arm. And the second phase modulation means R2 and L2 that perform phase modulation according to the light intensity of the RZ type clock signal light input from the optical waveguide, and the first phase modulation means R1-1 and L1-1. Respectively multiplexes the clock signal light transmitted by the first interference arm and the clock signal light for phase modulation control input from the first optical waveguide into two systems of the combined signal light First optical interference type branching and splitting means for splitting into two, two first optical waveguide arms for transmitting two signal light beams output from the first optical interference type branching and splitting means, and the two Two systems transmitted by the first optical waveguide arm Each of the first optical waveguide arms and the second optical interference type multiplexing / branching means for multiplexing the signal light and splitting the combined signal light into two systems. First optical phase modulation control means for phase-modulating the clock signal light transmitted by one interference arm according to the light intensity of the clock signal light for phase modulation control input from the first optical waveguide; A first phase adjusting means provided on at least one of the two first optical waveguide arms and capable of adjusting the phase of the signal light in accordance with the amount of injected current supplied from outside; A first light receiving means for receiving the signal light output from the one not connected to the first interference arm among the two optical output ports of the two optical interference type branching means; 2 phase modulation means R2, L2 respectively A third signal for multiplexing the clock signal light transmitted by the interfering arm and the clock signal light for phase modulation control input from the second optical waveguide, and demultiplexing the combined signal light into two systems; An optical interference type coupling / branching unit, two second optical waveguide arms that transmit two signal light beams output from the third optical interference type coupling / branching unit, and the two second optical waveguide arms One for each of the second optical waveguide arm and the fourth optical interference type multiplexing / branching means for multiplexing the two signal light signals to be transmitted and demultiplexing the combined signal light into two systems. A second optical phase modulation which is provided and phase-modulates the clock signal light transmitted by the second interference arm according to the light intensity of the clock signal light for phase modulation control input from the second optical waveguide. Control means and at least one of the two second optical waveguide arms Both of the second phase adjusting means, which is provided on one side and can adjust the phase of the signal light according to the amount of injection current supplied from the outside, and the fourth optical interference type branching means A second light receiving means for receiving signal light output from the one not connected to the second interference arm among the optical output ports, and the third phase modulating means R1-2, L1- 2 is provided in each of two third optical waveguide arms and one each of the two third optical waveguide arms, and the clock signal light transmitted by the first interference arm is transmitted to the third optical waveguide. A third optical phase modulation control means for performing phase modulation in accordance with the light intensity of the phase modulation control clock signal light input from the first optical waveguide arm and at least one of the two third optical waveguide arms, Depending on the amount of injection current supplied from , Transmitted by the third phase adjusting means capable of adjusting the phase of the signal light, the clock signal light transmitted by the first interference arm, and one of the two third optical waveguide arms. A fifth optical interference type multiplexing / branching unit that multiplexes the combined clock signal light and demultiplexes the combined signal light into two systems, and a phase modulation control clock input from the third optical waveguide Sixth optical interference type multiplexing / branching that multiplexes the signal light and the clock signal light transmitted by the other of the two third optical waveguide arms and demultiplexes the combined signal light into two systems. And a third light receiving means for receiving the signal light output from one of the two optical output ports of the sixth optical interference type merging / branching means that is not connected to the first interference arm. The first optical propagation delay difference providing means DD-1 is configured as described above. Delay corresponding to the difference in optical propagation delay until the two RZ-type clock signal lights demultiplexed by one optical demultiplexing means SP-1 reach the first phase modulation means R1-1 and L1-1. Of the two systems of RZ type clock signal light input to the first phase modulation means R1-1 and L1-1 until the first phase modulation means R1-1 and L1-1 are reached. Two systems of RZ that are provided to the RZ-type clock signal light having the longer optical propagation delay, are further provided in the second optical waveguide, and are demultiplexed by the second optical demultiplexing means SP-2-1. A delay corresponding to the difference in optical propagation delay until the clock signal light reaches the second phase modulation means R2 and L2, and two RZ clocks inputted to the second phase modulation means R2 and L2. Of the signal light, the light propagation delay until reaching the second phase modulation means R2, L2. Second optical propagation delay difference applying means DD-2 for applying to the longer RZ type clock signal light, and the third optical demultiplexing means SP-2 provided in the third optical waveguide A delay corresponding to the difference in optical propagation delay until the two systems of RZ type clock signal light demultiplexed by -2 reach the third phase modulation means R1-2 and L1-2 is defined as the third phase. Of the two systems of RZ-type clock signal light input to the modulation means R1-2 and L1-2, the one having the longer optical propagation delay until reaching the third phase modulation means R1-2 and L1-2 A third optical propagation delay difference applying means DD-2-1 for applying to the RZ-type clock signal light; and a second optical modulator provided in each of the first phase modulating means R1-1 and L1-1. Of the two optical output ports of the optical interference type combining / branching means, the one not connected to the first light receiving means The phase-modulated clock signal light is output, and the second light receiving port out of the two optical output ports of the fourth optical interference type merging / branching means provided in each of the second phase modulation means R2 and L2. The phase-modulated clock signal light is output from the one not connected to the means, and the sixth optical interference type branching means provided in each of the third phase modulation means R1-2 and L1-2. Of the two optical output ports, the phase-modulated clock signal light is output from the one not connected to the third optical waveguide arm, and the first Mach-Zehnder interference type optical intensity modulation means MZ-1 The output signal light is obtained from one of the two optical output ports P-MZ-1-cross and P-MZ-1-bar.

  Further, one configuration example (fourth embodiment) of the high-speed chaotic optical signal generating optical circuit of the present invention is further provided in the first optical waveguide, and the first optical demultiplexing means SP-1 Optical delay means DT-1 for giving a delay of a predetermined delay time T-1 to the two demultiplexed RZ-type clock signal lights, and the second optical waveguide, Optical delay means D- for imparting a delay of a predetermined delay time T-2 (T-1 ≠ T-2) to the two systems of RZ type clock signal light demultiplexed by the optical demultiplexing means SP-2-1. It comprises at least one of T-2.

  In one configuration example (first to fourth embodiments) of the high-speed chaotic optical signal generation optical circuit according to the present invention, the optical phase modulation control means adjusts the optical intensity of the clock signal light for phase modulation control. Semiconductor optical amplifier having a property of changing the refractive index in response to the above, an optical waveguide structure including a quantum dot layer having a property of changing the refractive index in accordance with the light intensity of the clock signal light for phase modulation control, and the phase modulation control It is characterized by comprising any one of the semiconductor EA optical modulators in a constant voltage driving state having a property that the refractive index changes according to the light intensity of the clock signal light for use.

  According to the present invention, the RZ type clock signal light is input to the optical input port P-MZ-1-1 of the first Mach-Zehnder interference type light intensity modulation means MZ-1, and the first Mach-Zehnder interference type light intensity is input. The RZ type clock signal light output from either one of the two optical output ports P-MZ-1-cross and P-MZ-1-bar of the modulation means MZ-1 is demultiplexed into two systems. Two RZ type clock signal lights are used as phase modulation control clock signal lights, and phase modulation means R1 provided on each of the two interference arms in the first Mach-Zehnder interference type light intensity modulation means MZ-1. , L1 causes a phase difference in the RZ type clock signal light input from the optical input port P-MZ-1-1 and propagating through the two interference arms, so that the phase modulation control clock signal Can modulate the output light intensity of the inputted RZ type optical clock signal to the first Mach-Zehnder interferometer type optical intensity modulating means MZ-1 after in time than. As a result, in the present invention, the entire system can be simplified and integrated, and an ultra-high-speed optical random number generation request exceeding 10 Gb / s utilizing the characteristics of the optical chaos method suitable for high speed can be handled. It is possible to generate random numbers with high randomness. In the present invention, it is possible to realize high-speed random number data generation exceeding 10 Gb / s, which cannot be realized by a conventional random number generation program or a random number generation method using an electronic circuit. Further, in the present invention, it is possible to realize reproducibility and controllability that are indispensable for engineering applications, which has been difficult with a complicated system configuration such as a random number generation method using a chaos laser, and has high accuracy and System integration can be realized. Further, in the present invention, it is possible to realize the integration of the system that cannot be realized by the random number generation method using the optical chaos signal source. Further, in the present invention, by using a plurality of Mach-Zehnder interferometers that are controlled so as to have a certain relationship between the optical path length differences by controlling the optical path length difference between the two interference arms by the thermo-optic effect, There is no need to have an optical path length difference information storage device or temperature-based optical path length difference control unit like a device that realizes a chaotic mapping relationship with the output power from a Mach-Zehnder interferometer, which speeds up and integrates the system. Can be realized. Further, in the present invention, it is possible to realize reproducibility and controllability that are indispensable for engineering applications, which has been difficult with an apparatus that uses the optical chaos phenomenon of all light based on the nonlinear refractive index effect of an optical fiber. System integration can be realized. In the present invention, the first phase modulation means R1 and L1 are divided into the first optical interference type branching means, the two first optical waveguide arms, the second optical interference type branching means, and the first optical phase. By comprising the modulation control means, the first phase adjustment means, and the first light receiving means, sufficient optical phase modulation in the first phase modulation means R1 and L1 can be realized continuously. In particular, in the present invention, by providing the first light receiving means in the first phase modulating means R1 and L1, the first phase modulating means R1 and L1 can be obtained without giving an influence such as loss to the optical circuit. It is possible to perform initial adjustment of the effective length of each of the optical waveguide arms, and it is possible to improve the characteristics of the optical circuit and simplify and economically adjust the initial adjustment of the operating conditions of the optical circuit.

  Further, in the present invention, by providing the optical delay means DT-1 for giving a predetermined delay to the two systems of RZ type clock signal light demultiplexed by the first optical demultiplexing means SP-1, Furthermore, it becomes possible to generate a random number sequence with increased randomness.

  In the present invention, the light is output from one of the two light output ports P-MZ-2-cross and P-MZ-2-bar of the second Mach-Zehnder interference type light intensity modulation means MZ-2. Second phase modulation means provided on each of the two interference arms in the second Mach-Zehnder interference type light intensity modulation means MZ-2 using the RZ type clock signal light as the clock signal light for phase modulation control. By inputting to R2 and L2, a phase difference is generated in the RZ type clock signal light that is input from the optical input port P-MZ-2-1 and is propagating through the two interference arms. Phase modulation control is applied to the RZ-type clock signal light output from one of the two optical output ports P-MZ-2-cross and P-MZ-2-bar of the Zender interference type optical intensity modulation means MZ-2. As a clock signal light for use, it is input to the third phase modulation means R1-2 and L1-2 provided one by one on the two interference arms behind the first phase modulation means R1-1 and L1-1. By doing so, it becomes possible to generate a random number sequence with further increased randomness. In the present invention, the first phase modulation means R1-1 and L1-1 are divided into the first optical interference type branching means, the two first optical waveguide arms, the second optical interference type branching means, 1 optical phase modulation control means, first phase adjustment means, and first light receiving means, and the second phase modulation means R2 and L2 are composed of a third optical interference type branching means and two second An optical waveguide arm, a fourth optical interference type merging / branching unit, a second optical phase modulation control unit, a second phase adjustment unit, and a second light receiving unit are provided, and a third phase modulation unit R1-2, L1-2 includes two third optical waveguide arms, third optical phase modulation control means, third phase adjustment means, fifth optical interference type branching means, sixth optical interference type branching means, The first, second, and third phase modulation means R1-1, L1-1, R2, and L2 are continuously constructed. R1-2, it is possible to achieve sufficient optical phase modulation in L1-2. In particular, in the present invention, the first, second, and third light receiving means are provided to the first, second, and third phase modulation means R1-1, L1-1, R2, L2, R1-2, and L1-2. By providing the first, second, and third phase modulation means R1-1, L1-1, R2, L2, R1-2, and L1-2 without giving an extra influence such as loss to the optical circuit. It is possible to perform initial adjustment of the effective length of each of the optical waveguide arms, and it is possible to improve the characteristics of the optical circuit and simplify and economically adjust the initial adjustment of the operating conditions of the optical circuit.

  Further, in the present invention, the optical delay means DT- that gives a delay of a predetermined delay time T-1 to the two systems of RZ type clock signal light demultiplexed by the first optical demultiplexing means SP-1. 1 and optical delay means DT-2 for giving a delay of a predetermined delay time T-2 to the two systems of RZ type clock signal light demultiplexed by the second optical demultiplexing means SP-2-1. By providing at least one of the above, it becomes possible to generate a random number sequence with further increased randomness.

It is a block diagram which shows the structural example of the high-speed chaotic optical signal production | generation optical circuit which concerns on the 1st Embodiment of this invention. It is a schematic diagram of the optical power change of the clock signal light in the first embodiment of the present invention. It is a figure which shows the input timing of the input clock signal light to the optical input port in the 1st Embodiment of this invention, and the input timing of the input signal light to a phase modulation part. It is a figure which shows the example of the normalization optical output intensity | strength of the clock light pulse output from the optical output port in the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the other structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the other structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the other structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the other structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the other structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the other structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the other structural example of the phase modulation part which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the high-speed chaotic optical signal production | generation optical circuit which concerns on the 2nd Embodiment of this invention. It is a figure which shows the input timing of the input clock signal light to the optical input port in the 2nd Embodiment of this invention, and the input timing of the input signal light to a phase modulation part. It is a figure which shows the time-sequential return map of the optical signal according to normal chaotic dynamics. It is a figure which shows the time-sequential dynamic history relationship of the optical signal according to the high-speed chaotic optical signal generation circuit which concerns on the 2nd Embodiment of this invention. It is a figure which shows the time series return map of the optical signal according to the high-speed chaotic optical signal generation circuit which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structural example of the high-speed chaotic optical signal production | generation optical circuit which concerns on the 3rd Embodiment of this invention. It is a figure which shows the input timing of the input clock signal light to the optical input port in the 3rd Embodiment of this invention, and the input timing of the input signal light to a phase modulation part. It is a figure which shows the time series return map of the optical signal according to the high-speed chaotic optical signal generation circuit which concerns on the 3rd Embodiment of this invention. It is a block diagram which shows the structural example of the high-speed chaotic optical signal production | generation optical circuit which concerns on the 4th Embodiment of this invention. Input timing of the input clock signal light to the optical input port of the second Mach-Zehnder interferometric light intensity modulator in the fourth embodiment of the present invention and the phase modulator in the second Mach-Zehnder interferometric light intensity modulator It is a figure which shows the input timing of the input signal light to. It is a figure which shows the time-sequential dynamic history relationship of the optical signal according to the high-speed chaotic optical signal generation circuit which concerns on the 4th Embodiment of this invention. It is a figure which shows the time-sequential return map of the optical signal according to the high-speed chaotic optical signal generation circuit which concerns on the 4th Embodiment of this invention. It is a block diagram which shows the other structural example of the high-speed chaotic optical signal production | generation optical circuit which concerns on the 4th Embodiment of this invention. It is a block diagram which shows the other structural example of the high-speed chaotic optical signal production | generation optical circuit which concerns on the 4th Embodiment of this invention.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of a high-speed chaotic optical signal generating optical circuit according to the first embodiment of the present invention.
The high-speed chaotic optical signal generation optical circuit according to the present embodiment includes a Mach-Zehnder interference light intensity modulation unit MZ-1 and an optical output port P-MZ-1- described later of the Mach-Zehnder interference light intensity modulation unit MZ-1. An RZ (Return to Zero) type clock signal light output from the cross is split into two systems, an optical demultiplexing unit SP-1, and two systems of RZ type clock signals are demultiplexed by the optical demultiplexing unit SP-1. Two systems in which a delay corresponding to a difference in light propagation delay until light reaches phase modulators R1 and L1 (described later) in Mach-Zehnder interference type light intensity modulator MZ-1 is input to phase modulators R1 and L1 Of the RZ type clock signal light, the optical propagation delay difference providing unit DD-1 for applying to the RZ type clock signal light having a longer optical propagation delay until reaching the phase modulation units R1 and L1. The

  The Mach-Zehnder interference type light intensity modulation unit MZ-1 includes an optical input port P-MZ-1-1 that receives an RZ type clock signal light having a constant peak light power output from a clock signal light source (not shown), Two interference arms that transmit the RZ-type clock signal light input to the input port P-MZ-1-1, and two optical output ports P-MZ-1- provided at the ends of the two interference arms cross, P-MZ-1-bar, and two optical signals demultiplexed by the optical demultiplexing unit SP-1 are phase modulation described later in the two interference arms of the Mach-Zehnder interferometric light intensity modulation unit MZ-1. Optical input ports P-R1 and P-L1 for phase modulation control for input to the units R1 and L1, and one RZ type clock signal light provided by two interference arms and transmitted by the interference arms, Optical input port -R1, composed of the phase modulation unit R1, L1 Metropolitan to phase modulation in accordance with the light intensity of the RZ type clock signal light input from the P-L1.

  In FIG. 1, 100 is an optical waveguide having one end connected to the optical input port P-MZ-1-1 and the other end connected to the input of the phase modulation unit L1, and 101 has one end disposed close to the optical waveguide 100. An optical waveguide having one end connected to the input of the phase modulation unit R1, 102 an optical waveguide having one end connected to the output of the phase modulation unit L1, and the other end connected to the optical output port P-MZ-1-bar, 103 One end is an optical waveguide that is connected to the output of the phase modulation unit R <b> 1, the other end is connected to the optical output port P-MZ-1-cross, and a part thereof is disposed close to the optical waveguide 102.

  The optical waveguides 100 and 102 constitute one interference arm of the Mach-Zehnder interference type light intensity modulation unit MZ-1, and the optical waveguides 101 and 103 constitute the other interference arm of the Mach-Zehnder interference type light intensity modulation unit MZ-1. doing. An optical signal leaks between the optical waveguide 100 and the optical waveguide 101, and the optical signal input to the optical waveguide 100 is also input to the optical waveguide 101. The optical signal leaks between the optical waveguide 102 and the optical waveguide 103.

  An optical waveguide 104 has one end connected to the optical output port P-MZ-1-cross and the other end connected to the input of the optical demultiplexing unit SP-1, and 105 has one end connected to the optical demultiplexing unit SP-1. An optical waveguide connected to the first output and having the other end connected to the input of the optical propagation delay difference applying unit DD-1, and one end connected to the second output of the optical demultiplexing unit SP-1 An optical waveguide having one end connected to the optical input port P-R1, 109 is an optical waveguide having one end connected to the output of the optical propagation delay difference adding unit DD-1 and the other end connected to the optical input port P-L1 It is.

  FIG. 2 shows changes in the optical power of the clock signal light input to the optical input port P-MZ-1-1. Thus, the clock signal light input from the clock signal light source (not shown) to the optical input port P-MZ-1-1 is RZ type signal light having a constant peak light power.

  In a standard Mach-Zehnder interferometric light intensity modulation unit, a state in which no phase difference occurs when light propagates through two interference arms constituting an interferometer is a state in which modulation driving is not performed. 100% of the optical signal is output from the optical output port of the interference arm on the different side with respect to the interference arm on the input side. In a state where the phase difference is π when light propagates through the two interference arms, 100% of the optical signal is output from the optical output port of the interference arm on the same side as the optical input port.

  Therefore, when the clock signal light is input from the optical input port P-MZ-1-1 to the high-speed chaos optical signal generation optical circuit shown in FIG. 1, the first clock optical pulse p0 is the optical input port P-MZ- 100% is output from the optical output port P-MZ-1-cross of the interference arm on the side different from 1-1, and is demultiplexed into two optical clock pulses p0-1 and p0-2 by the optical demultiplexing unit SP-1. Then, after being delayed by the optical propagation delay difference adding unit DD-1, the optical input ports P-R1 and P-L1 are input to the phase modulating units R1 and L1, respectively.

3A shows the input timing of the input clock signal light to the optical input port P-MZ-1-1, and FIG. 3B shows the input timing of the input signal light to the phase modulator R1. FIG. 3C is a diagram showing the input timing of the input signal light to the phase modulation unit L1.
As shown in FIG. 3B, the optical propagation delay difference is applied at the timing between the clock light pulse p0 input to the optical input port P-MZ-1-1 and the clock light pulse p1 of the next time step. The clock light pulse p0-1 to which the optical propagation delay by the part DD-1 is not given is input to the phase modulation part R1. On the other hand, as shown in FIG. 3C, an optical propagation delay is imparted by the optical propagation delay difference providing unit DD-1 at a timing between the clock optical pulse p1 and the clock optical pulse p2 of the next time step. The generated clock light pulse p0-2 is input to the phase modulator L1.

  In the phase modulation unit R1, immediately before the clock light pulse p1 is input from the optical input port P-MZ-1-1 via the optical waveguides 100 and 101, the clock optical pulse p0-1 from the optical input port P-R1. Is input, the refractive index changes according to the light intensity of the clock light pulse p0-1. Thus, the phase modulation unit R1 modulates the phase of the clock light pulse p1 according to the light intensity of the clock light pulse p0-1 (mutual phase modulation).

  On the other hand, in the phase modulation unit L1, the clock light pulse p0-2 is output from the optical input port P-L1 immediately after the clock light pulse p1 is input from the optical input port P-MZ-1-1 via the optical waveguide 100. Is input, the refractive index changes according to the light intensity of the clock light pulse p0-2. Thus, the phase modulation unit L1 modulates the phase of the clock light pulse p2 according to the light intensity of the clock light pulse p0-2 (mutual phase modulation).

  As a result, after the clock light pulse p0-1 is input to the phase modulation unit R1, until the clock light pulse p0-2 is input to the phase modulation unit L1, the Mach-Zehnder interference light intensity modulation unit MZ-1 A phase difference occurs between the two interference arms, and the light output intensity of the clock light pulse p1 output from the light output port P-MZ-1-cross is modulated.

  Similarly, it is demultiplexed by the optical demultiplexing unit SP-1 at the timing between the clock optical pulse p1 input to the optical input port P-MZ-1-1 and the clock optical pulse p2 of the next time step. Of the clock light pulses p1-1 and p1-2, the clock light pulse p1-1 to which the light propagation delay by the light propagation delay difference applying unit DD-1 is not applied is input to the phase modulation unit R1. On the other hand, at the timing between the clock light pulse p2 and the clock light pulse p3 of the next time step, the clock light pulse p1-2 to which the light propagation delay is imparted by the light propagation delay difference imparting unit DD-1 is provided. Is input to the phase modulation unit L1.

  The phase modulation unit R1 receives a clock light pulse p1- that is a demultiplexed light of the clock light pulse p1 immediately before the clock light pulse p2 is input from the optical input port P-MZ-1-1 through the optical waveguides 100 and 101. When 1 is input from the optical input port P-R1, the phase of the clock light pulse p2 is modulated according to the light intensity of the clock light pulse p1-1.

  The phase modulation unit L1 receives a clock light pulse p1-2 that is a demultiplexed light of the clock light pulse p1 immediately after the clock light pulse p2 is input from the optical input port P-MZ-1-1 through the optical waveguide 100. When input from the optical input port P-L1, the phase of the clock light pulse p3 is modulated in accordance with the light intensity of the clock light pulse p1-2. As a result, the optical output intensity of the clock optical pulse p2 output from the optical output port P-MZ-1-cross is modulated.

  As described above, at the timing between the clock light pulse p (t) (t = 0, 1, 2, 3,...) And the clock light pulse p (t + 1) of the next time step, One clock optical pulse p (t) output from the output port P-MZ-1-cross and demultiplexed by the optical demultiplexing unit SP-1 is input to the phase modulation unit R1, and the clock optical pulse p (t + 1) and The other clock optical pulse p output from the optical output port P-MZ-1-cross and demultiplexed by the optical demultiplexing unit SP-1 at the timing between the clock optical pulse p (t + 2) of the next time step. (T) is input to the phase modulation unit L1. As a result, the optical output intensity of the clock optical pulse p (t + 1) output from the optical output port P-MZ-1-cross is modulated. Thus, the modulation of the clock light pulses p1, p2, p3,.

  FIG. 4 is a diagram illustrating a normalized light output intensity obtained by normalizing the light intensity of the clock light pulse output from the light output port P-MZ-1-cross of the Mach-Zehnder interference type light intensity modulator MZ-1. This shows a case where the amount of phase modulation generated in the clock light pulse of the next time step by the clock light pulse output from the optical output port P-MZ-1-cross is 1.8261π.

  The clock output from the optical output port P-MZ-1-cross under the condition that the output is 100% from the optical output port P-MZ-1-cross of the Mach-Zehnder interference type optical intensity modulator MZ-1. By setting the phase modulation units R1 and L1 so that the amount of phase modulation generated by the optical pulse in the clock optical pulse at the next time step is sufficient and appropriate, for example, as shown in FIG. The intensity of the clock light pulse output from the optical output port P-MZ-1-cross becomes a chaotic state in time series, and at the same time the intensity of the clock light pulse output from the optical output port P-MZ-1-bar It becomes a chaos state in the series.

  The reason why the intensity of the clock light pulse output from the optical output port P-MZ-1-bar of the Mach-Zehnder interference type optical intensity modulator MZ-1 is also in a chaos state in time series is that the total light intensity of the clock light pulse is The clock light pulse having the remaining light intensity obtained by subtracting the light intensity of the same clock light pulse output from the light output port P-MZ-1-cross is output from the light output port P-MZ-1-bar. is there.

  Thus, in the present embodiment, the behavior of the optical output intensity of the output clock signal light output from the optical output port P-MZ-1-cross can be made messy. If the light intensity at 100% output is set to 1 and the threshold value is set to 0.5, and the light intensity of the output clock signal light in which the light intensity is in a chaotic state in time series is larger than the threshold value, the binarized signal When a binarization process is performed in which the value of 1 is 1 and the light intensity of the output clock signal light is less than or equal to the threshold value, the value of the binarized signal is set to 0. A binary random number sequence is obtained.

  In this embodiment, it is possible to realize high-speed random number data generation exceeding 10 Gb / s, which cannot be realized by a conventional random number generation program or a random number generation method using an electronic circuit. Also, in this embodiment, the reproducibility and controllability that are indispensable for engineering applications, which was difficult with a complicated system configuration such as the random number generation method using a chaotic laser disclosed in Non-Patent Document 1, is realized. In addition, higher accuracy and system integration can be realized.

  Further, in this embodiment, it is possible to realize system integration that cannot be realized by the random number generation method using the optical chaos signal source disclosed in Patent Document 1. Further, in the present embodiment, by using a plurality of Mach-Zehnder interferometers that are controlled so as to give a certain relationship to the optical path length difference by controlling the optical path length difference between the two interference arms by the thermo-optic effect, There is no need to have an optical path length difference information storage device or temperature-based optical path length difference control unit like a device that realizes a chaotic mapping relationship with the output power from each Mach-Zehnder interferometer, and the system is speeded up and integrated. Can be realized.

  In addition, in this embodiment, it is possible to realize reproducibility and controllability that are indispensable for engineering applications, which has been difficult with an apparatus using an optical chaos phenomenon of all light based on the nonlinear refractive index effect of an optical fiber. Further, system integration can be realized.

Next, the phase modulation units R1 and L1 of the present embodiment will be described in more detail. FIG. 5 is a block diagram illustrating a configuration example of the phase modulation unit R1.
The phase modulation unit R1 is a Mach-Zehnder interference circuit and is transmitted by the interference arm of the Mach-Zehnder interference type optical intensity modulation unit MZ-1 and input to the optical input port 1007 (hereinafter referred to as phase-modulated signal). And RZ type clock signal light (hereinafter referred to as phase modulation control signal light) that is demultiplexed by the optical demultiplexing unit SP-1 and input to the optical input port 1008 (P-R1 in FIG. 1). Multimode interference coupler (MMI) b1, which is an optical interference type multiplexing / branching means that multiplexes and splits the combined signal light into two systems, and two signal lights output from multimode interference coupler b1 are transmitted. Multi-mode interference, which is an optical interference type combining / branching unit that multiplexes two optical waveguide arms to be transmitted and two optical signals transmitted by the two optical waveguide arms and demultiplexes the combined optical signals into two systems Cap b2, optical phase modulation control units c1 and c2 that are provided one by one on two optical waveguide arms and phase-modulate the phase-modulated signal light according to the light intensity of the phase modulation control signal light, and two optical waveguide arms Connected to one optical output port of the multimode interference coupler b2 and a phase adjustment unit d1 that can adjust the phase of the signal light according to the amount of injection current supplied from the outside. It is comprised from the light-receiving part e1.

  5, 1010 is an optical waveguide having one end connected to the optical input port 1007 of the phase modulation unit R1 and the other end connected to the first optical input port of the multimode interference coupler b1, and 1011 has one end connected to the phase modulation unit R1. An optical waveguide connected to the optical input port 1008 and connected to the second optical input port of the multimode interference coupler b1 at the other end, and 1012 has the other end connected to the first optical output port of the multimode interference coupler b1. Is connected to the optical input port of the optical phase modulation controller c1, 1013 is connected to the second optical output port of the multimode interference coupler b1, and the other end is the optical input port of the optical phase modulation controller c2. The optical waveguide 1014 is connected to the optical output port of the optical phase modulation controller c1 and the other end is connected to the optical input port of the phase adjuster d1. An optical waveguide 1015 has one end connected to the optical output port of the optical phase modulation control unit c2 and the other end connected to the second optical input port of the multimode interference coupler b2, and 1016 has an optical output from the phase adjustment unit d1. An optical waveguide connected to the port and having the other end connected to the first optical input port of the multimode interference coupler b2, 1018 has one end connected to the first optical output port of the multimode interference coupler b2 and the other end receiving the light. An optical waveguide 1019 connected to the optical input port e1 is an optical waveguide having one end connected to the second optical output port of the multimode interference coupler b2 and the other end connected to the optical output port 1009 of the phase modulator R1. is there.

The optical waveguides 1012, 1014, and 1016 constitute one optical waveguide arm of the phase modulation unit R 1, and the optical waveguides 1013 and 1015 constitute the other optical waveguide arm of the phase modulation unit R 1.
The configuration of the phase modulation unit L1 is the same as that of the phase modulation unit R1. In the case of the phase modulation unit R1, the optical input port 1007 is connected to the optical waveguide 101 in FIG. 1, the optical input port 1008 (P-R1 in FIG. 1) is connected to the optical waveguide 106, and the optical output port 1009 is connected to the optical waveguide 103. Connected to. In the case of the phase modulation unit L1, the optical input port 1007 is connected to the optical waveguide 100 in FIG. 1, the optical input port 1008 (P-L1 in FIG. 1) is connected to the optical waveguide 109, and the optical output port 1009 is connected to the optical waveguide 102. Connected to.

  Next, operations of the phase modulation units R1 and L1 shown in FIG. 5 will be described. The multimode interference coupler b1 combines the phase-modulated signal light input to the optical input port 1007 and the phase modulation control signal light input to the optical input port 1008, and combines the combined signal light into two systems. Demultiplex.

  Next, the optical phase modulation control unit c1 receives one of the combined signal light of the phase modulated signal light and the phase modulation control signal light output from the multimode interference coupler b1, and outputs the phase modulated signal light in phase. Phase modulation is performed according to the light intensity of the modulation control signal light. When the pulse of the phase modulation control signal light is input immediately before the pulse of the phase modulated signal light is input, the refractive index of the optical phase modulation control unit c1 changes according to the light intensity of the phase modulation control signal light. To do. Thus, the optical phase modulation control unit c1 modulates the phase of the phase-modulated signal light according to the light intensity of the phase modulation control signal light (mutual phase modulation).

Similarly, the optical phase modulation control unit c2 receives the other of the combined signal light of the phase modulated signal light and the phase modulation control signal light output from the multimode interference coupler b1, and outputs the phase modulated signal light in phase. Phase modulation is performed according to the light intensity of the modulation control signal light.
As the optical phase modulation controllers c1 and c2 that perform phase modulation as described above, there are semiconductor optical amplifiers (SOA) having an optical waveguide structure. Further, an optical waveguide structure including a quantum dot layer may be used as the optical phase modulation control units c1 and c2, or a semiconductor EA (Electro-Absorption) optical modulator in a constant voltage driving state is used as the optical phase modulation control units c1 and c2. It may be used as

Next, the multi-mode interference coupler b2 combines the two signal lights output from the optical phase modulation controllers c1 and c2, and demultiplexes the combined signal lights into two systems.
At this time, the phase adjusting unit d1 selectively outputs the phase-modulated signal light from the second optical output port (optical output port 1009) of the multimode interference coupler b2, and the phase modulation control signal light is output from the multimode interference coupler. It is adjusted so as to be selectively output from the first optical output port b2. Therefore, the phase-modulated signal light is output to the optical output port 1009, and the phase-modulation control signal light is output to the light receiving unit e1.

  In the high-speed chaotic optical signal generation optical circuit of the present embodiment, when the phase modulation control signal light is output together with the phase-modulated signal light without being sufficiently removed from the phase modulation units R1 and L1, the phase modulation control signal light However, there is a problem that it works as noise in later phase modulation in time series, and it becomes difficult to perform sufficient phase modulation.

  Therefore, in the present embodiment, the phase adjustment unit d1 is provided on one of the two optical waveguide arms that connect the multimode interference coupler b1 and the multimode interference coupler b2. The phase adjustment unit d1 can adjust the phase of the signal light according to the amount of injection current supplied from the outside. By adjusting the phase of the signal light output from the optical phase modulation control unit c1 by the phase adjustment unit d1, the phase-modulated signal light is selectively output from the second optical output port of the multimode interference coupler b2. The phase difference between the two optical waveguide arms can be adjusted after manufacturing so that the phase modulation control signal light is selectively output from the first optical output port of the multimode interference coupler b2. As a result, in the present embodiment, sufficient optical phase modulation can be realized in the phase modulation units R1 and L1 continuously.

  However, in order to perform adjustment by the phase adjustment unit d1, it is necessary to measure and evaluate the optical output power from the first and second optical output ports of the multimode interference coupler b2. The second optical output port of the multimode interference coupler b2 of the phase modulation unit R1 is connected to the optical output port P-MZ-1-cross of the Mach-Zehnder interference type optical intensity modulation unit MZ-1 via the optical output port 1009. Has been. Therefore, by measuring and evaluating the optical output power from the optical output port P-MZ-1-cross, the optical output power from the second optical output port of the multimode interference coupler b2 of the phase modulator R1 is measured and evaluated. It is possible. Similarly, the second optical output port of the multimode interference coupler b2 of the phase modulation unit L1 is connected to the optical output port P-MZ-1-bar of the Mach-Zehnder interference type optical intensity modulation unit MZ-1. By measuring and evaluating the optical output power from the optical output port P-MZ-1-bar, the optical output power from the second optical output port of the multimode interference coupler b2 of the phase modulator L1 can be measured and evaluated. Is possible.

  On the other hand, since the first optical output port of the multimode interference coupler b2 is not used in normal times, it is not necessary to extract the output outside the phase modulation units R1 and L1. Therefore, when the high-speed chaotic optical signal generating optical circuit of the present embodiment is made of a planar optical circuit, the first optical output port of the multimode interference coupler b2 is closed on the planar optical circuit. Therefore, it is difficult to extract the signal light from the first optical output port of the multimode interference coupler b2 without affecting the optical circuit such as loss. Even if an optical output port for taking out the optical output to the outside is provided outside the phase modulators R1 and L1 on the assumption that the optical circuit is affected by a loss or the like, the optical output port is connected to the optical output port during phase adjustment. On the other hand, a separate optical coupling system and optical power detector must be prepared.

  Therefore, in the present embodiment, the light receiving unit e1 that can output a current corresponding to the received light intensity to the outside is connected to the first optical output port of the multimode interference coupler b2. This eliminates the need to pull out the first optical output port of the multimode interference coupler b2 to the outside, and eliminates the need for an optical coupling system and an optical power detector.

  Then, the optical output power from the optical output port P-MZ-1-cross is measured and evaluated, and the optical output power detected by the light receiving unit e1 of the phase modulation unit R1 is evaluated, so that the phase-modulated signal light is The phase modulation control signal light is selectively output from the first optical output port of the multimode interference coupler b2 of the phase modulation unit R1, and is selectively output from the second optical output port of the multimode interference coupler b2 of the phase modulation unit R1. So that the phase adjustment unit d1 of the phase modulation unit R1 can be adjusted. Similarly, the optical output power from the optical output port P-MZ-1-bar is measured and evaluated, and the optical output power detected by the light receiving unit e1 of the phase modulating unit L1 is evaluated to thereby evaluate the phase-modulated signal light. Is selectively output from the second optical output port of the multimode interference coupler b2 of the phase modulation unit L1, and the phase modulation control signal light is selected from the first optical output port of the multimode interference coupler b2 of the phase modulation unit L1. Therefore, the phase adjustment unit d1 of the phase modulation unit L1 can be adjusted so as to be output in a normal manner.

  Thus, in the present embodiment, it is possible to perform the initial effective length adjustment of the optical waveguide arms of the phase modulation units R1 and L1 without extra effects such as loss on the optical circuit, and the optical circuit It is possible to improve the characteristics and simplify and economically adjust the initial adjustment of the operating conditions of the optical circuit.

  Further, the phase modulation units R1 and L1 may be configured as shown in FIG. In the configuration of FIG. 6, the phase adjustment unit d2 is provided on the other of the two optical waveguide arms connecting the multimode interference coupler b1 and the multimode interference coupler b2 instead of the phase adjustment unit d1. In the configuration of FIG. 6, the other end of the optical waveguide 1015 may be connected to the optical input port of the phase adjustment unit d2. Reference numeral 1017 in FIG. 6 denotes an optical waveguide having one end connected to the optical output port of the phase adjusting unit d2 and the other end connected to the second optical input port of the multimode interference coupler b2.

The phase adjustment unit d2 can adjust the phase of the signal light according to the amount of injection current supplied from the outside. In the configuration of FIG. 6, the phase-modulated signal light is adjusted from the second optical output port of the multimode interference coupler b2 by adjusting the phase of the signal light output from the optical phase modulation control unit c2 by the phase adjustment unit d2. The phase difference between the two optical waveguide arms can be adjusted after manufacturing so that the phase modulation control signal light is selectively output and the phase modulation control signal light is selectively output from the first optical output port of the multimode interference coupler b2. it can. The method of adjusting the phase adjustment unit d2 using the light receiving unit e1 is the same as that of the phase adjustment unit d1.
Further, the phase modulation units R1 and L1 may be configured as shown in FIG. The configuration of FIG. 7 is provided with both phase adjustment units d1 and d2.

  Further, the phase modulation units R1 and L1 may be configured as shown in FIG. In the configuration of FIG. 8, instead of providing the phase adjustment unit d1 between the optical phase modulation control unit c1 and the multimode interference coupler b2 as shown in FIG. 5, the multimode interference coupler b1 and the optical phase modulation control unit c1 It is provided in between. In this case, the other end of the optical waveguide 1012 may be connected to the optical input port of the phase adjustment unit d1. Reference numeral 1020 in FIG. 8 denotes an optical waveguide having one end connected to the optical output port of the phase adjusting unit d1 and the other end connected to the optical input port of the optical phase modulation control unit c1.

  Further, the phase modulation units R1 and L1 may be configured as shown in FIG. In the configuration of FIG. 9, instead of providing the phase adjustment unit d2 between the optical phase modulation control unit c2 and the multimode interference coupler b2 as shown in FIG. 6, the multimode interference coupler b1 and the optical phase modulation control unit c2 It is provided in between. In this case, the other end of the optical waveguide 1013 may be connected to the optical input port of the phase adjustment unit d2. Reference numeral 1021 in FIG. 9 denotes an optical waveguide having one end connected to the optical output port of the phase adjusting unit d2 and the other end connected to the optical input port of the optical phase modulation control unit c2.

  Further, the phase modulation units R1 and L1 may be configured as shown in FIG. The configuration of FIG. 10 is a combination of FIG. 8 and FIG. 9, wherein the phase adjustment unit d1 is provided between the multimode interference coupler b1 and the optical phase modulation control unit c1, and the phase adjustment unit d2 is provided with the multimode interference coupler b1 and the optical It is provided between the phase modulation control unit c2.

  Further, the phase modulation units R1 and L1 may be configured as shown in FIG. 11, the phase adjustment unit d1 is provided between the optical phase modulation control unit c1 and the multimode interference coupler b2 as shown in FIGS. 5 and 7, and the phase adjustment unit d2 is provided as shown in FIGS. This is provided between the multimode interference coupler b1 and the optical phase modulation controller c2.

  Further, the phase modulation units R1 and L1 may be configured as shown in FIG. In the configuration of FIG. 12, the phase adjustment unit d1 is provided between the multimode interference coupler b1 and the optical phase modulation control unit c1 as shown in FIGS. 8 and 10, and the phase adjustment unit d2 is provided as shown in FIGS. This is provided between the optical phase modulation controller c2 and the multimode interference coupler b2.

In this embodiment, the optical output port P-MZ-1-cross is connected to the input of the optical demultiplexing unit SP-1, but the optical output port P-MZ-1-bar and the optical demultiplexing are connected. You may make it connect with the input of part SP-1.
In the present embodiment, the output signal light of the high-speed chaotic optical signal generating optical circuit is output from two optical output ports P-MZ-1-bar and P-MZ-1- of the Mach-Zehnder interference type optical intensity modulator MZ-1. What is necessary is just to obtain from either one of cross.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 13 is a block diagram showing a configuration example of a high-speed chaotic optical signal generating optical circuit according to the second embodiment of the present invention.
The high-speed chaos optical signal generation optical circuit according to the present embodiment is different from the high-speed chaos optical signal generation optical circuit according to the first embodiment in two RZ-type clocks that are demultiplexed by the optical demultiplexing unit SP-1. An optical delay unit DT-1 for adding a predetermined delay to each signal light is added.

  In the present embodiment, the other end of the optical waveguide 105 is connected to the first optical input port of the optical delay unit DT-1, and the other end of the optical waveguide 106 is connected to the second optical delay unit DT-1. It may be connected to the optical input port. 13 in FIG. 13 is an optical waveguide having one end connected to the first optical output port of the optical delay unit DT-1 and the other end connected to the input of the optical propagation delay difference providing unit DD-1. An optical waveguide having one end connected to the second optical output port of the optical delay unit DT-1 and the other end connected to the optical input port PR-1. The configuration of the phase modulation units R1 and L1 is as described in the first embodiment.

  Next, the operation of the high-speed chaotic optical signal generating optical circuit according to the present embodiment will be described. When the clock signal light is input from the optical input port P-MZ-1-1 to the high-speed chaotic optical signal generation optical circuit of the present embodiment, the first clock optical pulse p0 is the optical input port P-MZ-1- 100% is output from the optical output port P-MZ-1-cross of the interference arm on the side different from 1, and is split into two optical clock pulses p0-1 and p0-2 by the optical demultiplexing unit SP-1. Subsequently, a delay is given by the optical propagation delay difference giving unit DD-1, and then input from the optical input ports P-R1 and P-L1 to the phase modulation units R1 and L1, respectively.

  14A shows the input timing of the input clock signal light to the optical input port P-MZ-1-1, and FIG. 14B shows the input timing of the input signal light to the phase modulator R1-1. FIG. 14C is a diagram illustrating the input timing of the input signal light to the phase modulation unit L1-1. As shown in FIG. 14 (B), the clock light pulse pM1 after a certain delay step time T-1 in time series from the clock light pulse p0 input to the optical input port P-MZ-1-1 and the next The clock optical pulse p0-1 to which the optical propagation delay by the optical propagation delay difference applying unit DD-1 is not applied is input to the phase modulation unit R1 at the timing between the clock optical pulse pM2 of the time step Is done. On the other hand, as shown in FIG. 14C, the light propagation delay is imparted by the light propagation delay difference providing unit DD-1 at the timing between the clock light pulse pM2 and the clock light pulse pM3 of the next time step. The generated clock light pulse p0-2 is input to the phase modulator L1.

  The delay step time T-1 is a delay time given to the clock signal light by the optical delay unit DT-1. That is, the clock signal light output from the optical output port P-MZ-1-cross is demultiplexed into two by the optical demultiplexing unit SP-1, and the delay step time T-1 by the optical delay unit DT-1. Is added to the optical input port P-R1, and the other clock signal light is further delayed by the optical propagation delay difference adding unit DD-1. Is input to the optical input port P-L1.

The phase modulation unit R1 receives the clock optical pulse p0 input from the optical input port P-R1 immediately before the clock optical pulse pM2 is input from the optical input port P-MZ-1-1 via the optical waveguides 100 and 101. The phase of the clock light pulse pM2 is modulated according to the light intensity of -1.
On the other hand, the phase modulation unit L1 receives the clock light pulse p0 input from the optical input port P-L1 immediately after the clock light pulse pM2 is input from the optical input port P-MZ-1-1 via the optical waveguide 100. The phase of the clock light pulse pM3 is modulated according to the light intensity of -2.

  As a result, after the clock light pulse p0-1 is input to the phase modulation unit R1, until the clock light pulse p0-2 is input to the phase modulation unit L1, the Mach-Zehnder interference light intensity modulation unit MZ-1 A phase difference occurs between the two interference arms, and the light output intensity of the clock light pulse pM2 output from the light output port P-MZ-1-cross is modulated.

  Similarly, at the timing between the clock light pulse pM2 after the delay step time T-1 from the clock light pulse p1 input to the optical input port P-MZ-1-1 and the clock light pulse pM3 at the next time step. Of the clock light pulses p1-1 and p1-2 demultiplexed by the light demultiplexing unit SP-1, the clock light pulse to which the light propagation delay by the light propagation delay difference providing unit DD-1 is not given p1-1 is input to the phase modulation unit R1. On the other hand, at the timing between the clock light pulse pM3 and the clock light pulse pM4 of the next time step, the clock light pulse p1-2 to which the light propagation delay is imparted by the light propagation delay difference imparting part DD-1 is provided. Is input to the phase modulation unit L1.

The phase modulation unit R1 outputs a clock light pulse p1- that is a demultiplexed light of the clock light pulse p1 immediately before the clock light pulse pM3 is input from the optical input port P-MZ-1-1 through the optical waveguides 100 and 101. When 1 is input from the optical input port P-R1, the phase of the clock light pulse pM3 is modulated according to the light intensity of the clock light pulse p1-1.
The phase modulation unit L1 receives a clock light pulse p1-2 that is a demultiplexed light of the clock light pulse p1 immediately after the clock light pulse pM3 is input from the optical input port P-MZ-1-1 via the optical waveguide 100. When input from the optical input port P-L1, the phase of the clock light pulse pM4 is modulated according to the light intensity of the clock light pulse p1-2. As a result, the optical output intensity of the clock optical pulse pM3 output from the optical output port P-MZ-1-cross is modulated.

  As described above, at the timing between the clock light pulse p (i + Ns) (Ns is an integer of 1 or more) and the clock light pulse p (i + Ns + 1) of the next time step, the optical output port P-MZ-1- One clock light pulse p (i) output from the cross and demultiplexed by the optical demultiplexing unit SP-1 is input to the phase modulation unit R1, and the clock light pulse p (i + Ns + 1) and the clock light pulse of the next time step are input. The other clock light pulse p (i) output from the optical output port P-MZ-1-cross and demultiplexed by the optical demultiplexing unit SP-1 at the timing between p (i + Ns + 2) is the phase modulation unit L1. Is input. As a result, the optical output intensity of the clock optical pulse p (i + Ns + 1) output from the optical output port P-MZ-1-cross is modulated. In this way, the clock light pulses pM2, pM3, pM4,... Are continuously modulated.

  The clock output from the optical output port P-MZ-1-cross under the condition that the output is 100% from the optical output port P-MZ-1-cross of the Mach-Zehnder interference type optical intensity modulator MZ-1. By setting the phase modulation units R1 and L1 so that the amount of phase modulation generated in the clock light pulse positioned behind the pulse on the time axis is sufficient and appropriate, for example, FIG. As shown in the figure, the intensity of the clock light pulse output from the optical output port P-MZ-1-cross becomes a chaotic state in time series, and at the same time, output from the optical output port P-MZ-1-bar. The intensity of the clock light pulse is also chaotic in time series.

  When the optical delay unit DT-1 is not provided, that is, when T-1 = 0, the clock light pulse of the immediately preceding time step i-1 is used for the light intensity modulation of the clock light pulse of the time step i. Will be used. At this time, the light intensity at the time of 100% output is set to 1 and the threshold value is set to 0.5, and the light intensity of the output clock signal light whose light intensity is in a chaos state in time series is larger than the threshold value. If a binarization process is performed in which the value of the binarized signal is 1, and the value of the binarized signal is 0 if the light intensity of the output clock signal light is equal to or less than the threshold value, a binary random number sequence is obtained.

  However, when the optical delay unit DT-1 is not provided, the output clock signal light obtained from the optical output port P-MZ-1-cross or P-MZ-1-bar is a physical noise used as a physical random number source. Thus, it is not suitable for application fields that are required to have completely random characteristics. The reason is that a system that follows a dynamic system that generally behaves like a chaotic behaves unpredictably and randomly in the long run, but the light intensity between adjacent pulses on a time step is, for example, shown in FIG. Because there is a clear relationship / correlation as shown in the return map, it becomes easy to predict the light intensity at the next time step from the light intensity at a certain time step. This is because it is not a good behavior. In the example of FIG. 15, it is shown that there is a correlation between the normalized light output intensity at time step i and the normalized light output intensity at the next time step i + 1.

  For this reason, in the random number generation method using a chaotic laser disclosed in Non-Patent Document 1, after two chaotic output optical signals are obtained from two chaotic lasers, the two independent chaotic output lights are obtained. By applying logical arithmetic processing to the signal, a random sequence with high randomness can be obtained even in the short term.

  On the other hand, in the high-speed chaotic optical signal generation optical circuit of the present embodiment, the problem that the output clock signal light is not messy when viewed in a short time in a time series is added without preparing a plurality of chaotic light sources. This is realized without applying logical operation processing. That is, in this embodiment, the problem is caused by providing the optical delay unit DT-1 so that the delay step time T-1 is an arbitrary value equal to or longer than one step time (period of the clock light pulse). Solve. Here, the delay step time T-1 is, for example, a time that is an integral multiple of the period of the clock light pulse.

  When the optical delay unit DT-1 is provided so that the delay step time T-1 becomes an arbitrary value equal to or longer than one step time, the pulse train of the output clock signal light is p (i), p (i + 1), p (i + 2),..., p (i + Ns-1) Ns chaotic pulse trains and p (i + Ns), p (i + Ns + 1), p (i + Ns + 2),..., p (i + 2Ns-1) ) Ns chaotic state pulse trains of p (i + Ns), p (i + Ns + 1), p (i + Ns + 2),..., P (i + 2Ns−1) pulse trains of p (i + 2Ns−1) and p (I + 2Ns), p (i + 2Ns + 1), p (i + 2Ns + 2),... It becomes the column are combined as shown in FIG. 16. Ns is the number of clock light pulses in the delay step time T-1, and is an integer value of 1 or more.

  Due to the combination of such pulses, the difference in the initial values due to slight fluctuations is physically unavoidable in the real world, and thus the pulse train of the Ns chaotic states is unpredictable and messy in the long term. In addition, the relationship between the pulse train of Ns chaotic states and another pulse train of Ns chaotic states becomes unpredictable. Therefore, in the present embodiment, when T-1 = 0, it is clear that the light intensity of a pulse at an arbitrary time step i adjacent in time series and the light intensity of a pulse at time step i + 1 can be seen. The relation / regularity can be lost as shown in FIG. 17, and a random number sequence with increased randomness can be generated. As described above, in the present embodiment, it is possible to generate a random number sequence with further increased randomness as compared with the first embodiment.

In this embodiment, the optical output port P-MZ-1-cross is connected to the input of the optical demultiplexing unit SP-1, but the optical output port P-MZ-1-bar and the optical demultiplexing are connected. You may make it connect with the input of part SP-1.
In the present embodiment, the output signal light of the high-speed chaotic optical signal generating optical circuit is output from two optical output ports P-MZ-1-cross, P of the first Mach-Zehnder interference type optical intensity modulation means MZ-1. It may be obtained from any one of -MZ-1-bar.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. FIG. 18 is a block diagram showing a configuration example of a high-speed chaos optical signal generation optical circuit according to the third embodiment of the present invention.
The high-speed chaotic optical signal generation optical circuit according to the present embodiment includes Mach-Zehnder interference type optical intensity modulation units MZ-1 and MZ-2 and an optical output port P of the first Mach-Zehnder interference type optical intensity modulation unit MZ-1. An optical demultiplexing unit SP-1 for demultiplexing the RZ type clock signal light output from MZ-1-cross into two systems, and an optical output port P-MZ- of the Mach-Zehnder interference type optical intensity modulation unit MZ-2 An optical demultiplexing unit SP-2-1 that demultiplexes an optical signal output from 2-cross into two systems, and an optical output port P-MZ-2-bar of the Mach-Zehnder interference type optical intensity modulation unit MZ-2. An optical demultiplexing unit SP-2-2 for demultiplexing the output optical signal into two systems, and two systems of RZ type clock signal light demultiplexed by the optical demultiplexing unit SP-1 are Mach-Zehnder interference type optical intensities. A phase modulation unit R1- described later in the modulation unit MZ-1. , L1-1, a delay corresponding to the difference in optical propagation delay until reaching L1-1, among the two RZ-type clock signal lights input to the phase modulators R1-1 and L1-1, the phase modulator R1-1. , L1-1, the optical propagation delay difference providing unit DD-1 for applying to the longer RZ type clock signal light and the optical demultiplexing unit SP-2-1. The delay corresponding to the difference in optical propagation delay until the two systems of RZ type clock signal light reach phase modulation units R2 and L2 (to be described later) in the Mach-Zehnder interference type optical intensity modulation unit MZ-2 is represented by the phase modulation unit R2. , L2 of the two RZ type clock signal lights input to L2, the optical propagation delay difference giving part D for giving to the RZ type clock signal light having a longer light propagation delay until reaching the phase modulation parts R2 and L2. -D-2 and two systems of R demultiplexed by the optical demultiplexing unit SP-2-2 A delay corresponding to a difference in optical propagation delay until the clock signal light reaches a phase modulation unit R1-2, L1-2, which will be described later, in the Mach-Zehnder interference light intensity modulation unit MZ-1. 2 of the two RZ-type clock signal lights input to L1-2, the RZ-type clock signal light having a longer optical propagation delay until reaching the phase modulation units R1-2 and L1-2. It is comprised from the optical propagation delay difference provision part DD-2-1.

  The Mach-Zehnder interference type optical intensity modulation unit MZ-1 of the present embodiment is an optical input port P-MZ-1 that receives an RZ type clock signal light having a constant peak optical power output from a clock signal light source (not shown). -1 and two interference arms that transmit the RZ type clock signal light input to the optical input port P-MZ-1-1, and two optical output ports P provided at the ends of the two interference arms -MZ-1-cross, P-MZ-1-bar and the two optical signals demultiplexed by the optical demultiplexing unit SP-1 in the two interference arms of the Mach-Zehnder interference type optical intensity modulation unit MZ-1 Are divided by phase modulation control optical input ports P-R1-1 and P-L1-1 for input to phase modulation units R1-1 and L1-1, which will be described later, and an optical demultiplexing unit SP-2-2. Mach-Zehnder interference type with two optical signals Optical input ports P-R1-2, P-L1-2 for phase modulation control for input to phase modulation units R1-2, L1-2, which will be described later, in the two interference arms of the intensity modulation unit MZ-1. One RZ type clock signal light provided on each of the two interference arms and transmitted by the interference arm is used as the light of the RZ type clock signal light input from the optical input ports P-R1-1 and P-L1-1. One is provided in each of the phase modulation units R1-1 and L1-1 that performs phase modulation according to the intensity and the two interference arms behind the phase modulation units R1-1 and L1-1, and is transmitted by the interference arm. Phase modulators R1-2 and L1-2 for phase-modulating the RZ-type clock signal light in accordance with the light intensity of the RZ-type clock signal light input from the optical input ports P-R1-2 and P-L1-2; Consists of

  The Mach-Zehnder interference light intensity modulator MZ-2 includes an optical input port P-MZ-2-1 that receives an RZ-type clock signal light having a constant peak light power output from a clock signal light source (not shown). Two interference arms that transmit the RZ type clock signal light input to the optical input port P-MZ-2-1, and two optical output ports P-MZ-2 provided at the ends of the two interference arms -Cross, P-MZ-2-bar, and the two optical signals demultiplexed by the optical demultiplexing unit SP-2-1 will be described later in the two interference arms of the Mach-Zehnder interferometric light intensity modulation unit MZ-2. Optical input ports P-R2 and P-L2 for phase modulation control for input to the phase modulation units R2 and L2 to be transmitted, and one RZ type clock signal provided by two interference arms and transmitted by the interference arms Light Port P-R2, composed of the phase modulation unit R2, L2 Metropolitan to phase modulation in accordance with the light intensity of the RZ type clock signal light input from the P-L2.

  In FIG. 18, reference numeral 200 denotes an optical waveguide having one end connected to the optical input port P-MZ-1-1 and the other end connected to the input of the phase modulation unit L1-1, and 201 is arranged close to the optical waveguide 200. The other end of the optical waveguide is connected to the input of the phase modulation unit R1-1. 202 is an optical waveguide having one end connected to the output of the phase modulation unit L1-1 and the other end connected to the input of the phase modulation unit L1-2. Waveguide 203 has one end connected to the output of phase modulator R1-1 and the other end connected to the input of phase modulator R1-2. 204 has one end connected to the output of phase modulator L1-2. An optical waveguide having the other end connected to the optical output port P-MZ-1-bar, 205 has one end connected to the output of the phase modulator R1-2, and the other end connected to the optical output port P-MZ-1-cross And a part of the optical waveguide 204 is disposed in the vicinity. A waveguide.

  The optical waveguides 200, 202, and 204 constitute one interference arm of the Mach-Zehnder interference type light intensity modulation unit MZ-1, and the optical waveguides 201, 203, and 205 constitute the other of the Mach-Zehnder interference type light intensity modulation unit MZ-1. It constitutes an interference arm. An optical signal leaks between the optical waveguide 200 and the optical waveguide 201, and the optical signal input to the optical waveguide 200 is also input to the optical waveguide 201. Between the optical waveguide 204 and the optical waveguide 205, optical signal leakage occurs mutually.

  Reference numeral 206 denotes an optical waveguide having one end connected to the optical input port P-MZ-2-1 and the other end connected to the input of the phase modulation unit L2. Reference numeral 207 denotes one end arranged close to the optical waveguide 206 and the other end. Is an optical waveguide connected to the input of the phase modulation unit R2, 208 is an optical waveguide having one end connected to the output of the phase modulation unit L2 and the other end connected to the optical output port P-MZ-2-bar, and 209 is one end Is an optical waveguide that is connected to the output of the phase modulation unit R 2, the other end is connected to the optical output port P-MZ-2-cross, and a part thereof is disposed close to the optical waveguide 208.

  The optical waveguides 206 and 208 constitute one interference arm of the Mach-Zehnder interference type light intensity modulation unit MZ-2, and the optical waveguides 207 and 209 constitute the other interference arm of the Mach-Zehnder interference type light intensity modulation unit MZ-2. doing. An optical signal leaks between the optical waveguide 206 and the optical waveguide 207, and the optical signal input to the optical waveguide 206 is also input to the optical waveguide 207. Between the optical waveguide 208 and the optical waveguide 209, optical signal leakage occurs mutually.

  210 is an optical waveguide having one end connected to the optical output port P-MZ-1-cross and the other end connected to the input of the optical demultiplexing unit SP-1, and 211 is one end of the optical demultiplexing unit SP-1. An optical waveguide connected to the first output and having the other end connected to the input of the optical propagation delay difference applying unit DD-1, and one end 212 connected to the output of the optical propagation delay difference applying unit DD-1. An optical waveguide having the other end connected to the optical input port P-L1-1, 213 has one end connected to the second output of the optical demultiplexing unit SP-1, and the other end connected to the optical input port P-R1-1. Optical waveguide.

  An optical waveguide 216 has one end connected to the output of the optical propagation delay difference adding unit DD-2 and the other end connected to the optical input port P-L2. 219 has one end connected to the optical propagation delay difference adding unit D-. An optical waveguide connected to the output of D-2-1 and having the other end connected to the optical input port PR1-2. 221 has one end connected to the optical output port P-MZ-2-cross and the other end connected to the optical component. An optical waveguide connected to the input of the wave part SP-2-1, 222 has one end connected to the first output of the optical demultiplexing part SP-2-1 and the other end connected to the optical propagation delay difference adding part DD-. 2 is connected to the second output of the optical demultiplexing unit SP-2-1 and the other end is connected to the optical input port P-R2. 224 is one end. Is connected to the optical output port P-MZ-2-bar and the other end is connected to the input of the optical demultiplexing unit SP-2-2. The optical path 225 has one end connected to the first output of the optical demultiplexing unit SP-2-2 and the other end connected to the input of the optical propagation delay difference providing unit DD-2-1. An optical waveguide having one end connected to the second output of the optical demultiplexing unit SP-2-2 and the other end connected to the optical input port P-L1-2.

  Changes in the optical power of the clock signal light input to the optical input ports P-MZ-1-1 and P-MZ-2-1 are as shown in FIG. The clock signal light input to the optical input ports P-MZ-1-1 and P-MZ-2-1 from a clock signal light source (not shown) is RZ type signal light having a constant peak light power.

  As the phase modulators R1-1, L1-1, R1-2, L1-2, R2, and L2, any one of the configurations shown in FIGS. 5 to 12 of the first embodiment can be used. In the case of the phase modulation unit R1-1, the optical input port 1007 is connected to the optical waveguide 201, the optical input port 1008 (P-R1-1 in FIG. 18) is connected to the optical waveguide 213, and the optical output port 1009 is the optical waveguide. 203. In the case of the phase modulation unit L1-1, the optical input port 1007 is connected to the optical waveguide 200, the optical input port 1008 (P-L1-1 in FIG. 18) is connected to the optical waveguide 212, and the optical output port 1009 is the optical waveguide. 202.

  In the case of the phase modulation unit R2, the optical input port 1007 is connected to the optical waveguide 207, the optical input port 1008 (P-R2 in FIG. 18) is connected to the optical waveguide 223, and the optical output port 1009 is connected to the optical waveguide 209. The In the case of the phase modulation unit L2, the optical input port 1007 is connected to the optical waveguide 206, the optical input port 1008 (P-L2 in FIG. 18) is connected to the optical waveguide 216, and the optical output port 1009 is connected to the optical waveguide 208. The

  On the other hand, the phase modulation unit R1-2 and the phase modulation unit L1-2 are different from the phase modulation units R1, L1, R1-1, L1-1, R2, and L2 in port connection and internal circuit operation. That is, in the case of the phase modulation unit R1-2 and phase modulation unit L1-2, 1008 and 1009 are optical input ports, and 1007 is an optical output port. In the case of the phase modulation unit R1-2, the optical input port 1009 is connected to the optical waveguide 203, the optical input port 1008 (P-R1-2 in FIG. 18) is connected to the optical waveguide 219, and the optical output port 1007 is the optical waveguide. 205 is connected. In the case of the phase modulation unit L1-2, the optical input port 1009 is connected to the optical waveguide 202, the optical input port 1008 (P-L1-2 in FIG. 18) is connected to the optical waveguide 226, and the optical output port 1007 is the optical waveguide. 204.

  The multimode interference coupler b2 of the phase modulation unit R1-2 and phase modulation unit L1-2 receives the phase-modulated signal light input to the optical input port 1009 and the signal light from the optical phase modulation control unit c2 (FIG. 6, FIG. 7, in the case of FIG. 12, the signal light from the phase adjustment unit d2 is multiplexed, the combined signal light is demultiplexed into two systems, and one signal light is connected to the light receiving unit e1. The second optical output port (in the case of FIGS. 6, 8 to 10 and FIG. 12, connected to the optical phase modulation control unit c1). Output to the second optical output port).

The optical phase modulation control unit c1 of the phase modulation unit R1-2 and phase modulation unit L1-2 receives the signal light output from the multimode interference coupler b2, and uses the phase-modulated signal light as the light of the phase modulation control signal light. Phase modulation is performed according to the intensity.
The multimode interference coupler b1 of the phase modulation unit R1-2 and phase modulation unit L1-2 receives the phase modulation control signal light input to the optical input port 1008 and the signal light from the optical phase modulation control unit c1 (FIG. 8, FIG. 10, in the case of FIG. 12, the signal light from the phase adjustment unit d1) is multiplexed, the combined signal light is split into two systems, and one signal light is connected to the optical phase modulation control unit c2. To the first optical output port (the first optical output port connected to the phase adjustment unit d2 in the case of FIGS. 9 to 11), and the other signal light is connected to the port 1007. Output to output port.

The optical phase modulation control unit c2 of the phase modulation unit R1-2 and phase modulation unit L1-2 receives the signal light output from the multimode interference coupler b1, and uses the phase-modulated signal light as the light of the phase modulation control signal light. Phase modulation is performed according to the intensity.
Then, the phase modulation units d1 and d2 of the phase modulation unit R1-2 and the phase modulation unit L1-2 are selected from the second optical output port (optical output port 1007) of the phase-modulated signal light of the multimode interference coupler b1. And the phase modulation control signal light may be adjusted so as to be selectively output from the first optical output port of the multimode interference coupler b2 connected to the light receiving unit e1.

  Thus, although the port connections are different, the phase modulator R1-2 and phase modulator L1-2 also realize the same operation as the phase modulators R1, L1, R1-1, L1-1, R2, and L2. Can do.

  Next, the operation of the high-speed chaotic optical signal generating optical circuit according to the present embodiment will be described. When the clock signal light is input from the optical input port P-MZ-1-1 to the high-speed chaotic optical signal generation optical circuit of the present embodiment, the first clock optical pulse p0 is the optical input port P-MZ-1- 100% is output from the optical output port P-MZ-1-cross of the interference arm on the side different from 1, and is split into two optical clock pulses p0-1 and p0-2 by the optical demultiplexing unit SP-1. Subsequently, after the delay difference is given by the optical propagation delay difference giving means D-D-1, the signals are input from the optical input ports P-R1-1 and P-L1-1 to the phase modulators R1-1 and L1-1, respectively. Is done.

  19A shows the input timing of the input clock signal light to the optical input port P-MZ-1-1, and FIG. 19B shows the input timing of the input signal light to the phase modulator R1-1. FIG. 19C is a diagram illustrating the input timing of the input signal light to the phase modulation unit L1-1. As shown in FIG. 19B, the optical propagation delay difference is applied at the timing between the clock light pulse p0 input to the optical input port P-MZ-1-1 and the clock light pulse p1 of the next time step. The clock light pulse p0-1 to which the optical propagation delay by the part D-D-1 is not given is input to the phase modulation part R1-1. On the other hand, as shown in FIG. 19C, an optical propagation delay is imparted by the optical propagation delay difference providing unit DD-1 at a timing between the clock optical pulse p1 and the clock optical pulse p2 of the next time step. The generated clock light pulse p0-2 is input to the phase modulator L1-1.

  The phase modulator R1-1 is input from the optical input port P-R1-1 immediately before the clock optical pulse p1 is input from the optical input port P-MZ-1-1 via the optical waveguides 200 and 201. The phase of the clock light pulse p1 is modulated according to the light intensity of the clock light pulse p0-1.

  On the other hand, the phase modulation unit L1-1 is input from the optical input port P-L1-1 immediately after the clock optical pulse p1 is input from the optical input port P-MZ-1-1 via the optical waveguide 200. The phase of the clock light pulse p1 is modulated according to the light intensity of the clock light pulse p0-2.

  As a result, Mach-Zehnder interferometric light intensity modulation is performed after the clock light pulse p0-1 is input to the phase modulation unit R1-1 until the clock light pulse p0-2 is input to the phase modulation unit L1-1. A phase difference is generated between the two interference arms of the unit MZ-1, and the optical output intensity of the clock light pulse p1 output from the optical output port P-MZ-1-cross is modulated.

  Similarly, it is demultiplexed by the optical demultiplexing unit SP-1 at the timing between the clock optical pulse p1 input to the optical input port P-MZ-1-1 and the clock optical pulse p2 of the next time step. Of the clock light pulses p1-1 and p1-2, the clock light pulse p1-1 to which the light propagation delay by the light propagation delay difference applying unit DD-1 is not applied is input to the phase modulation unit R1-1. The On the other hand, at the timing between the clock light pulse p2 and the clock light pulse p3 of the next time step, the clock light pulse p1-2 to which the light propagation delay is imparted by the light propagation delay difference imparting unit DD-1 is provided. Is input to the phase modulation unit L1-1.

  The phase modulation unit R1-1 receives a clock light pulse that is a demultiplexed light of the clock light pulse p1 immediately before the clock light pulse p2 is input from the optical input port P-MZ-1-1 through the optical waveguides 200 and 201. When p1-1 is input from the optical input port PR1-1, the phase of the clock light pulse p2 is modulated according to the light intensity of the clock light pulse p1-1.

  The phase modulation unit L1-1 receives a clock light pulse p1- that is a demultiplexed light of the clock light pulse p1 immediately after the clock light pulse p2 is input from the optical input port P-MZ-1-1 via the optical waveguide 200. When 2 is input from the optical input port P-L1-1, the phase of the clock light pulse p2 is modulated according to the light intensity of the clock light pulse p1-2. As a result, the optical output intensity of the clock optical pulse p2 output from the optical output port P-MZ-1-cross is modulated.

  As described above, at the timing between the clock light pulse p (t) (t = 0, 1, 2, 3,...) And the clock light pulse p (t + 1) of the next time step, One clock optical pulse p (t) output from the output port P-MZ-1-cross and demultiplexed by the optical demultiplexing unit SP-1 is input to the phase modulation unit R1-1, and the clock optical pulse p (t + 1) ) And the clock light pulse p (t + 2) of the next time step, the other clock light output from the optical output port P-MZ-1-cross and demultiplexed by the optical demultiplexing unit SP-1 The pulse p (t) is input to the phase modulation unit L1-1. As a result, the optical output intensity of the clock optical pulse p (t + 1) output from the optical output port P-MZ-1-cross is modulated. Thus, the modulation of the clock light pulses p1, p2, p3,.

  The clock output from the optical output port P-MZ-1-cross under the condition that the output is 100% from the optical output port P-MZ-1-cross of the Mach-Zehnder interference type optical intensity modulator MZ-1. By setting the phase modulators R1-1 and L1-1 so that the amount of phase modulation generated by the optical pulse in the clock optical pulse at the next time step is sufficient and appropriate, for example, as shown in FIG. As in the case, the intensity of the clock light pulse output from the optical output port P-MZ-1-cross becomes a chaotic state in time series, and at the same time, the clock light pulse output from the optical output port P-MZ-1-bar The intensity of chaos also becomes chaos in time series.

  However, the output clock signal light whose optical output intensity is chaotic in time series is required to have completely random characteristics like physical noise used as a physical random number source. Not suitable for the field. The reason is as described in FIG.

  Therefore, in the present embodiment, an additional logic operation process is applied to the problem that the output clock signal optical pulse train of the Mach-Zehnder interference type optical intensity modulation unit MZ-1 is not messy when viewed in a short time in a time series. It has been solved. In the present embodiment, a Mach-Zehnder interference light intensity modulator MZ-2 is provided separately from the Mach-Zehnder interference light intensity modulator MZ-1, and the light output port P of the Mach-Zehnder interference light intensity modulator MZ-2 is provided. -Under the condition that 100% is output from the MZ-2-cross, the clock light pulse output from the optical output port P-MZ-2-cross is clocked at the next time step in the phase modulators R2 and L2. The phase modulation amount generated in the optical pulse is set to be sufficient and appropriate, and the clock signal light synchronized with the clock signal light input to the optical input port P-MZ-1-1 is optically input. Input is also made to the port P-MZ-2-1.

  When the clock signal light is input from the optical input port P-MZ-2-1 of the Mach-Zehnder interference light intensity modulation unit MZ-2, similarly to the Mach-Zehnder interference light intensity modulation unit MZ-1, the first clock The optical pulse p0 is output 100% from the optical output port P-MZ-2-cross of the interference arm on the side different from the optical input port P-MZ-2-1, and is clocked by the optical demultiplexing unit SP-2-1. After being demultiplexed into two pulses p0-1 and p0-2 and subsequently given a delay difference by the optical propagation delay difference providing means DD-2, the phase is respectively transmitted from the optical input ports PR2, P-L2. The signals are input to the modulation units R2 and L2.

  Then, at the timing between the clock light pulse p0 input to the optical input port P-MZ-2-1 and the clock light pulse p1 of the next time step, the light by the light propagation delay difference providing unit DD-2 The clock light pulse p0-1 to which the propagation delay is not given is input to the phase modulation unit R2. On the other hand, at the timing between the clock light pulse p1 and the clock light pulse p2 of the next time step, the clock light pulse p0-2 to which the light propagation delay is applied by the light propagation delay difference providing unit DD-2. Is input to the phase modulation unit L2.

  The phase modulation unit R2 receives the clock optical pulse p0 input from the optical input port P-R2 immediately before the clock optical pulse p1 is input from the optical input port P-MZ-2-1 through the optical waveguides 206 and 207. The phase of the clock light pulse p1 is modulated according to the light intensity of -1. The phase modulation unit L2 receives the clock light pulse p0-2 input from the optical input port P-L2 immediately after the clock light pulse p1 is input from the optical input port P-MZ-2-1 through the optical waveguide 206. The phase of the clock light pulse p1 is modulated according to the light intensity.

  As a result, the Mach-Zehnder interference light intensity modulation unit MZ-2 is from the time when the clock light pulse p0-1 is input to the phase modulation unit R2 to the time when the clock light pulse p0-2 is input to the phase modulation unit L2. A phase difference occurs between the two interference arms, and the optical output intensity of the clock optical pulse p1 output from the optical output port P-MZ-2-cross is modulated.

  As described above, at the timing between the clock light pulse p (t) (t = 0, 1, 2, 3,...) And the clock light pulse p (t + 1) of the next time step, One clock optical pulse p (t) output from the output port P-MZ-2-cross and demultiplexed by the optical demultiplexing unit SP-2-1 is input to the phase modulation unit R2, and the clock optical pulse p (t + 1) ) And the clock light pulse p (t + 2) of the next time step, the other output from the optical output port P-MZ-2-cross and demultiplexed by the optical demultiplexing unit SP-2-1 The clock light pulse p (t) is input to the phase modulation unit L2. As a result, the optical output intensity of the clock optical pulse p (t + 1) output from the optical output port P-MZ-2-cross is modulated. Thus, similarly to the Mach-Zehnder interference type light intensity modulation unit MZ-1, the Mach-Zehnder interference type light intensity modulation unit MZ-2 continuously modulates the clock light pulses p1, p2, p3,. Done.

  The pulse train of the output clock signal light output from the optical output port P-MZ-2-cross of the Mach-Zehnder interference type light intensity modulation unit MZ-2 is the optical output port P of the Mach-Zehnder interference type light intensity modulation unit MZ-1. The pulse sequence of the output clock signal light output from -MZ-1-cross matches the clock timing, and the optical output intensity is chaotic in time series. In addition, the chaotic state generated in the pulse train of the output clock signal light output from the optical output port P-MZ-2-cross of the Mach-Zehnder interference type optical intensity modulation unit MZ-2 is a chaotic dynamic viewpoint. The pulse train of the output clock signal light from the optical output port P-MZ-1-cross is not affected at all.

  Therefore, due to the butterfly effect that is one of the characteristics of chaos, the optical output intensity of the pulse at a certain time step i included in the output clock signal optical pulse train from the optical output port P-MZ-1-cross is A state that cannot be predicted based on the light output intensity of the pulse at the time step i-1 immediately before the time step i included in the output clock signal optical pulse train from the output port P-MZ-2-cross, ie, light The output clock signal light from the output port P-MZ-1-cross and the output clock signal light from the optical output port P-MZ-2-cross are in a messy state.

  Next, an optical propagation delay difference adding unit DD-2 with respect to two output clock signal lights output from the optical output port P-MZ-2-bar and demultiplexed by the optical demultiplexing unit SP-2-2. −1 to give a propagation delay difference, and two output clock signal lights to which the propagation delay difference is given from the optical input ports P-R1-2 and P-L1-2 of the Mach-Zehnder interference type optical intensity modulation unit MZ-1. Input to the phase modulation units R1-2 and L1-2.

  The phase modulation units R1-2 and L1-2 are provided independently of the phase modulation units R1-1 and L1-1, and are input from the phase modulation units R1-1 and L1-1 via the optical waveguides 203 and 202. The phase modulation amount with respect to the maximum value of the intensity of the input clock signal light is set to be sufficient and appropriate. For this reason, the phase modulators R1-2 and L1-2 cause a phase difference between the two interference arms of the Mach-Zehnder interference light intensity modulator MZ-1.

  Thus, in the present embodiment, the chaotic state generated in the output clock signal optical pulse train from the optical output port P-MZ-2-bar is replaced with the output clock signal optical pulse train from the optical output port P-MZ-1-cross. By convolving with respect to the chaos state occurring in the optical output port P-MZ-1-cross, the behavior of the optical output intensity of the output clock signal light from the optical output port P-MZ-1-cross can be made messy. In the present embodiment, when the optical circuit unit including the Mach-Zehnder interference type optical intensity modulation unit MZ-1, the optical demultiplexing unit SP-1, and the optical propagation delay difference providing unit DD-1 is driven alone. As shown in FIG. 20, the relationship of the light intensity between adjacent pulses on the time step, as shown in FIG. 20, can be lost, and a random number sequence with increased randomness can be generated. As described above, in the present embodiment, it is possible to generate a random number sequence with further increased randomness as compared with the first embodiment.

  Further, in the present embodiment, the phase-modulated signal is obtained by using any one of the configurations in FIGS. 5 to 12 as the phase modulation units R1-1, L1-1, R1-2, L1-2, R2, and L2. At the same time as phase modulation is applied to the light, the phase modulation control signal light is removed to a sufficient extent, and only the phase-modulated signal light is phase-modulated R1-1, L1-1, R1-2, L1-2, R2, The light can be selectively output from the optical output port of L2. As a result, in the present embodiment, sufficient optical phase modulation can be realized in the phase modulators R1-1, L1-1, R1-2, L1-2, R2, and L2.

  In this embodiment, the optical output port P-MZ-1-cross is connected to the input of the optical demultiplexing unit SP-1, but the optical output port P-MZ-1-bar and the optical demultiplexing are connected. You may make it connect with the input of part SP-1. Further, the optical output port P-MZ-2-bar is connected to the input of the optical demultiplexing unit SP-2-1, and the optical output port P-MZ-2-cross and the optical demultiplexing unit SP-2-2 are connected. The input may be connected.

  In this embodiment, the output of the optical propagation delay difference providing unit DD-2-1 is connected to the optical input port PR1-2, but the optical propagation delay difference providing unit DD-2. -1 output is connected to the optical input port P-L1-2, and the optical propagation delay by the optical propagation delay difference providing unit DD-2-1 is provided among the outputs of the optical demultiplexing unit SP-2-2. The output that is not connected may be connected to the optical input port PR1-2.

  In this embodiment, RZ type clock signal light output from the same clock signal light source is demultiplexed in advance and input to the optical input ports P-MZ-1-1 and P-MZ-2-1. Alternatively, the RZ type clock signal light output from the first clock signal light source is input to the optical input port P-MZ-1-1 and is synchronized with the first clock signal light source. The RZ type clock signal light output from the second clock signal light source may be input to the optical input port P-MZ-2-1.

  In the present embodiment, the output signal light of the high-speed chaos optical signal generation optical circuit is output from two optical output ports P-MZ-1-cross and P-MZ- of the Mach-Zehnder interference type optical intensity modulator MZ-1. It may be obtained from any one of 1-bar. At this time, the light intensity at 100% output is set to 1 and the threshold is set to 0.5. If the light intensity of the output signal light is larger than the threshold, the value of the binarized signal is set to 1, and the output signal light If the light intensity is less than or equal to the threshold value, a binary random number sequence is obtained by performing binarization processing in which the value of the binarized signal is 0.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. FIG. 21 is a block diagram showing a configuration example of a high-speed chaotic optical signal generating optical circuit according to the fourth embodiment of the present invention.
The high-speed chaotic optical signal generation optical circuit according to the present embodiment is different from the high-speed chaotic optical signal generation optical circuit according to the third embodiment in that two RZ-type clocks demultiplexed by the optical demultiplexing unit SP-1. An optical delay unit DT-1 for giving a delay of a predetermined delay time T-1 to the signal light, and two systems of RZ type clock signal light demultiplexed by the optical demultiplexing unit SP-2-1, respectively. An optical delay unit DT-2 that adds a delay of a predetermined delay time T-2 (T-1 ≠ T-2) is added.

  In the present embodiment, the other end of the optical waveguide 211 is connected to the first optical input port of the optical delay unit DT-1, and the other end of the optical waveguide 213 is connected to the second optical delay unit DT-1. The other end of the optical waveguide 222 is connected to the first optical input port of the optical delay unit DT-2, and the other end of the optical waveguide 223 is connected to the optical delay unit DT-2. What is necessary is just to connect to a 2nd optical input port. 21 is an optical waveguide having one end connected to the first optical output port of the optical delay unit DT-1 and the other end connected to the input of the optical propagation delay difference providing unit DD-1. An optical waveguide having one end connected to the second optical output port of the optical delay unit DT-1 and the other end connected to the optical input port PR1-1, 229 has one end connected to the optical delay unit DT-2 An optical waveguide having the other end connected to the input of the optical propagation delay difference providing unit DD-2 and the other end of the optical waveguide 230 being the second light of the optical delay unit DT-2. An optical waveguide connected to the output port and connected to the optical input port PR2 at the other end.

  Next, the operation of the high-speed chaotic optical signal generating optical circuit according to the present embodiment will be described. In the high-speed chaos optical signal generation optical circuit of the present embodiment, when the Mach-Zehnder interference type optical intensity modulation unit MZ-2 does not exist and the clock signal light is input from the optical input port P-MZ-1-1, The first clock optical pulse p0 is output 100% from the optical output port P-MZ-1-cross of the interference arm on the side different from the optical input port P-MZ-1-1, and is clocked by the optical demultiplexing unit SP-1. After being demultiplexed into two optical pulses p0-1 and p0-2 and subsequently delayed by the optical propagation delay difference adding unit DD-1, the optical input ports P-R1-1 and P-L1 respectively. −1 to the phase modulators R1-1 and L1-1.

  14A to 14C, FIG. 14A shows the input timing of the input clock signal light to the optical input port P-MZ-1-1, and FIG. Indicates the input timing of the input signal light to the phase modulation section R1-1, and FIG. 14C shows the input timing of the input signal light to the phase modulation section L1-1.

  As shown in FIG. 14B, the clock light pulse pM1 after a certain delay step time T-1 from the clock light pulse p0 input to the optical input port P-MZ-1-1 in time series, At the timing between the clock light pulse pM2 of the next time step, the clock light pulse p0-1 to which the light propagation delay is not imparted by the light propagation delay difference imparting unit DD-1 is transmitted to the phase modulation unit R1- 1 is input. On the other hand, as shown in FIG. 14C, the light propagation delay is imparted by the light propagation delay difference providing unit DD-1 at the timing between the clock light pulse pM2 and the clock light pulse pM3 of the next time step. The generated clock light pulse p0-2 is input to the phase modulator L1-1.

  The delay step time T-1 is a delay time given to the clock signal light by the optical delay unit DT-1. That is, the clock signal light output from the optical output port P-MZ-1-cross is demultiplexed into two by the optical demultiplexing unit SP-1, and the delay step time T-1 by the optical delay unit DT-1. Is added to the optical input port P-R1-1 as it is, and the other clock signal light is further delayed by the optical propagation delay difference adding unit DD-1. After being given, it is inputted to the optical input port P-L1-1.

The phase modulator R1-1 is input from the optical input port P-R1-1 immediately before the clock optical pulse pM2 is input from the optical input port P-MZ-1-1 via the optical waveguides 200 and 201. The phase of the clock light pulse pM2 is modulated according to the light intensity of the clock light pulse p0-1.
On the other hand, the phase modulator L1-1 is input from the optical input port P-L1-1 immediately after the clock optical pulse pM2 is input from the optical input port P-MZ-1-1 via the optical waveguide 200. The phase of the clock light pulse pM3 is modulated according to the light intensity of the clock light pulse p0-2.

  As a result, Mach-Zehnder interferometric light intensity modulation is performed after the clock light pulse p0-1 is input to the phase modulation unit R1-1 until the clock light pulse p0-2 is input to the phase modulation unit L1-1. A phase difference is generated between the two interference arms of the unit MZ-1, and the optical output intensity of the clock optical pulse pM2 output from the optical output port P-MZ-1-cross is modulated.

  Similarly, at the timing between the clock light pulse pM2 after the delay step time T-1 from the clock light pulse p1 input to the optical input port P-MZ-1-1 and the clock light pulse pM3 at the next time step. Of the clock light pulses p1-1 and p1-2 demultiplexed by the light demultiplexing unit SP-1, the clock light pulse to which the light propagation delay by the light propagation delay difference providing unit DD-1 is not given p1-1 is input to the phase modulation unit R1-1. On the other hand, at the timing between the clock light pulse pM3 and the clock light pulse pM4 of the next time step, the clock light pulse p1-2 to which the light propagation delay is imparted by the light propagation delay difference imparting part DD-1 is provided. Is input to the phase modulation unit L1-1.

The phase modulation unit R1-1 receives a clock light pulse that is a demultiplexed light of the clock light pulse p1 immediately before the clock light pulse pM3 is input from the optical input port P-MZ-1-1 through the optical waveguides 200 and 201. When p1-1 is input from the optical input port PR1-1, the phase of the clock light pulse pM3 is modulated according to the light intensity of the clock light pulse p1-1.
The phase modulation unit L1-1 receives the clock light pulse p1-, which is the demultiplexed light of the clock light pulse p1, immediately after the clock light pulse pM3 is input from the optical input port P-MZ-1-1 via the optical waveguide 200. When 2 is input from the optical input port P-L1-1, the phase of the clock light pulse pM4 is modulated in accordance with the light intensity of the clock light pulse p1-2. As a result, the optical output intensity of the clock optical pulse pM3 output from the optical output port P-MZ-1-cross is modulated.

  As described above, at the timing between the clock light pulse p (i + Ns) (Ns is an integer of 1 or more) and the clock light pulse p (i + Ns + 1) of the next time step, the optical output port P-MZ-1- One clock light pulse p (i) output from the cross and demultiplexed by the optical demultiplexing unit SP-1 is input to the phase modulation unit R1-1, and the clock optical pulse p (i + Ns + 1) and the clock of the next time step At the timing between the optical pulse p (i + Ns + 2), the other clock optical pulse p (i) output from the optical output port P-MZ-1-cross and demultiplexed by the optical demultiplexing unit SP-1 is phase-modulated. Input to the part L1-1. As a result, the optical output intensity of the clock optical pulse p (i + Ns + 1) output from the optical output port P-MZ-1-cross is modulated. In this way, the clock light pulses pM2, pM3, pM4,... Are continuously modulated.

  The clock output from the optical output port P-MZ-1-cross under the condition that the output is 100% from the optical output port P-MZ-1-cross of the Mach-Zehnder interference type optical intensity modulator MZ-1. By setting the phase modulators R1-1 and L1-1 so that the amount of phase modulation generated by the optical pulse in the clock optical pulse at the next time step is sufficient and appropriate, for example, as shown in FIG. As in the case, the intensity of the clock light pulse output from the optical output port P-MZ-1-cross becomes a chaotic state in time series, and at the same time, the clock light pulse output from the optical output port P-MZ-1-bar The intensity of chaos also becomes chaos in time series.

  When the optical delay unit DT-1 is not provided, that is, when T-1 = 0, the clock light pulse of the immediately preceding time step i-1 is used for the light intensity modulation of the clock light pulse of the time step i. Will be used. At this time, the light intensity at the time of 100% output is set to 1 and the threshold value is set to 0.5, and the light intensity of the output clock signal light whose light intensity is in a chaos state in time series is larger than the threshold value. If a binarization process is performed in which the value of the binarized signal is 1, and the value of the binarized signal is 0 if the light intensity of the output clock signal light is equal to or less than the threshold value, a binary random number sequence is obtained.

  However, when the optical delay unit DT-1 is not provided, the output clock signal light obtained from the optical output port P-MZ-1-cross or P-MZ-1-bar is a physical noise used as a physical random number source. Thus, it is not suitable for application fields that are required to have completely random characteristics. The reason is as described in FIG.

  Therefore, in the present embodiment, an additional logic operation process is applied to the problem that the output clock signal optical pulse train of the Mach-Zehnder interference type optical intensity modulation unit MZ-1 is not messy when viewed in a short time in a time series. It has been solved. In the present embodiment, a Mach-Zehnder interference light intensity modulator MZ-2 is provided separately from the Mach-Zehnder interference light intensity modulator MZ-1, and the light output port P of the Mach-Zehnder interference light intensity modulator MZ-2 is provided. -Under the condition that 100% is output from the MZ-2-cross, the clock light pulse output from the optical output port P-MZ-2-cross is clocked at the next time step in the phase modulators R2 and L2. The phase modulation amount generated in the optical pulse is set to be sufficient and appropriate, and the clock signal light synchronized with the clock signal light input to the optical input port P-MZ-1-1 is optically input. Input is also made to the port P-MZ-2-1. Furthermore, in the present embodiment, the optical delay unit DT-1 is provided so that the delay step time T-1 is an arbitrary value equal to or longer than one step time (clock light pulse period). The optical delay unit DT-2 is provided so that the time T-2 becomes an arbitrary value equal to or longer than one step time. Here, the delay step times T-1 and T-2 are, for example, times that are integral multiples of the period of the clock light pulse, and T-1 ≠ T-2.

  When the clock signal light is input from the optical input port P-MZ-2-1 of the Mach-Zehnder interference light intensity modulation unit MZ-2, similarly to the Mach-Zehnder interference light intensity modulation unit MZ-1, the first clock The optical pulse p0 is output 100% from the optical output port P-MZ-2-cross of the interference arm on the side different from the optical input port P-MZ-2-1, and is clocked by the optical demultiplexing unit SP-2-1. The signals are split into two pulses p0-1 and p0-2, given a predetermined delay by the optical delay unit DT-2, and further given a delay difference by the optical propagation delay difference giving means DD-2. Then, the light is input from the optical input ports P-R2 and P-L2 to the phase modulators R2 and L2, respectively.

22A shows the input timing of the input clock signal light to the optical input port P-MZ-2-1, and FIG. 22B shows the input timing of the input signal light to the phase modulator R2. FIG. 22C is a diagram illustrating the input timing of the input signal light to the phase modulation unit L2.
As shown in FIG. 22B, the clock light pulse pM2 after a certain delay step time T-2 in time series from the clock light pulse p0 input to the optical input port P-MZ-2-1 and the next The clock optical pulse p0-1 to which the optical propagation delay by the optical propagation delay difference applying unit DD-2 is not applied is input to the phase modulating unit R2 at the timing between the clock optical pulse pM3 of the time step of Is done. On the other hand, as shown in FIG. 22C, an optical propagation delay is provided by the optical propagation delay difference providing unit DD-2 at the timing between the clock optical pulse pM3 and the clock optical pulse pM4 of the next time step. The generated clock light pulse p0-2 is input to the phase modulator L2.

  The delay step time T-2 is a delay time given to the clock signal light by the optical delay unit DT-2. That is, the clock signal light output from the optical output port P-MZ-2-cross is demultiplexed into two by the optical demultiplexing unit SP-2-1, and subsequently the delay step time by the optical delay unit DT-2. After the delay corresponding to T-2 is given, one clock signal light is inputted as it is to the optical input port PR2, and the other clock signal light is further delayed by the optical propagation delay difference giving unit DD-2. Is given to the optical input port P-L2.

The phase modulation unit R2 receives the clock optical pulse p0 input from the optical input port P-R2 immediately before the clock optical pulse pM3 is input from the optical input port P-MZ-2-1 through the optical waveguides 206 and 207. The phase of the clock light pulse pM3 is modulated according to the light intensity of -1.
On the other hand, the phase modulation unit L2 receives the clock light pulse p0 input from the optical input port P-L2 immediately after the clock light pulse pM3 is input from the optical input port P-MZ-2-1 through the optical waveguide 206. The phase of the clock light pulse pM4 is modulated according to the light intensity of -2.

  As a result, the Mach-Zehnder interference light intensity modulation unit MZ-2 is from the time when the clock light pulse p0-1 is input to the phase modulation unit R2 to the time when the clock light pulse p0-2 is input to the phase modulation unit L2. A phase difference occurs between the two interference arms, and the light output intensity of the clock light pulse pM3 output from the light output port P-MZ-2-cross is modulated.

  Similarly, at the timing between the clock light pulse pM3 after the delay step time T-2 from the clock light pulse p1 input to the optical input port P-MZ-2-1 and the clock light pulse pM4 at the next time step. Of the clock optical pulses p1-1 and p1-2 demultiplexed by the optical demultiplexing unit SP-2-1, the clock to which the optical propagation delay by the optical propagation delay difference applying unit DD-2 is not applied The optical pulse p1-1 is input to the phase modulation unit R2. On the other hand, at the timing between the clock light pulse pM4 and the clock light pulse pM5 of the next time step, the clock light pulse p1-2 to which the light propagation delay is imparted by the light propagation delay difference imparting part DD-2. Is input to the phase modulation unit L2.

The phase modulation unit R2 receives a clock light pulse p1- that is a demultiplexed light of the clock light pulse p1 immediately before the clock light pulse pM4 is input from the optical input port P-MZ-2-1 through the optical waveguides 206 and 207. When 1 is input from the optical input port P-R2, the phase of the clock light pulse pM4 is modulated in accordance with the light intensity of the clock light pulse p1-1.
The phase modulation unit L2 receives a clock light pulse p1-2 that is a demultiplexed light of the clock light pulse p1 immediately after the clock light pulse pM4 is input from the optical input port P-MZ-2-1 through the optical waveguide 206. When input from the optical input port P-L2, the phase of the clock light pulse pM5 is modulated according to the light intensity of the clock light pulse p1-2. As a result, the light output intensity of the clock light pulse pM4 output from the light output port P-MZ-2-cross is modulated.

  As described above, at the timing between the clock light pulse p (i + Qs) (Qs is an integer of 1 or more) and the clock light pulse p (i + Qs + 1) of the next time step, the optical output port P-MZ-2- One of the clock light pulses p (i) output from the cross and split by the optical branching unit SP-2-1 is input to the phase modulation unit R2, and the clock light pulse p (i + Qs + 1) and the clock of the next time step are input. At the timing between the optical pulse p (i + Qs + 2), the other clock optical pulse p (i) output from the optical output port P-MZ-2-cross and demultiplexed by the optical demultiplexing unit SP-2-1 is obtained. Input to the phase modulation unit L2. As a result, the optical output intensity of the clock optical pulse p (i + Qs + 1) output from the optical output port P-MZ-2-cross is modulated. Thus, similarly to the Mach-Zehnder interference type light intensity modulation unit MZ-1, the Mach-Zehnder interference type light intensity modulation unit MZ-2 continuously modulates the clock light pulses pM3, pM4, pM5,. Done.

  The pulse train of the output clock signal light output from the optical output port P-MZ-2-cross of the Mach-Zehnder interference type light intensity modulation unit MZ-2 is the optical output port P of the Mach-Zehnder interference type light intensity modulation unit MZ-1. The pulse sequence of the output clock signal light output from -MZ-1-cross matches the clock timing, and the optical output intensity is chaotic in time series. In addition, the chaotic state generated in the pulse train of the output clock signal light output from the optical output port P-MZ-2-cross of the Mach-Zehnder interference type optical intensity modulation unit MZ-2 is a chaotic dynamic viewpoint. The pulse train of the output clock signal light from the optical output port P-MZ-1-cross is not affected at all.

  Therefore, due to the butterfly effect that is one of the characteristics of chaos, the optical output intensity of the pulse at a certain time step i included in the output clock signal optical pulse train from the optical output port P-MZ-1-cross is A state that cannot be predicted based on the light output intensity of the pulse at the time step i-1 immediately before the time step i included in the output clock signal optical pulse train from the output port P-MZ-2-cross, ie, light The output clock signal light from the output port P-MZ-1-cross and the output clock signal light from the optical output port P-MZ-2-cross are in a messy state.

  Next, an optical propagation delay difference adding unit DD-2 with respect to two output clock signal lights output from the optical output port P-MZ-2-bar and demultiplexed by the optical demultiplexing unit SP-2-2. −1 to give a propagation delay difference, and two output clock signal lights to which the propagation delay difference is given from the optical input ports P-R1-2 and P-L1-2 of the Mach-Zehnder interference type optical intensity modulation unit MZ-1. Input to the phase modulation units R1-2 and L1-2.

  The phase modulation units R1-2 and L1-2 are provided independently of the phase modulation units R1-1 and L1-1, and are input from the phase modulation units R1-1 and L1-1 via the optical waveguides 203 and 202. The phase modulation amount with respect to the maximum value of the intensity of the input clock signal light is set to be sufficient and appropriate. For this reason, the phase modulators R1-2 and L1-2 cause a phase difference between the two interference arms of the Mach-Zehnder interference light intensity modulator MZ-1.

  Thus, in the present embodiment, the chaotic state generated in the output clock signal optical pulse train from the optical output port P-MZ-2-bar is replaced with the output clock signal optical pulse train from the optical output port P-MZ-1-cross. By convolving with respect to the chaos state occurring in the optical output port P-MZ-1-cross, the behavior of the optical output intensity of the output clock signal light from the optical output port P-MZ-1-cross can be made messy.

  At the same time, in this embodiment, the optical delay unit DT-1 is provided so that the delay step time T-1 becomes an arbitrary value equal to or longer than one step time (clock light pulse period), and the delay step time T- The optical delay unit DT-2 is provided so that 2 becomes an arbitrary value equal to or longer than one step time.

  When the optical delay unit DT-1 is provided so that the delay step time T-1 becomes an arbitrary value equal to or longer than one step time, the optical output port P-MZ of the Mach-Zehnder interference light intensity modulation unit MZ-1 The pulse train of the output clock signal light output from -1-cross is a pulse train of Ns chaos states of p (i), p (i + 1), p (i + 2), ..., p (i + Ns-1). , P (i + Ns), p (i + Ns + 1), p (i + Ns + 2),..., P (i + 2Ns−1), and the pulse train of Ns chaotic states is combined, and p (i + Ns), p (i + Ns + 1), p (i + Ns + 2),..., p (i + 2Ns-1) Ns chaotic pulse trains and p (i + 2Ns), p (i + 2Ns + 1), p (i + 2Ns + 2), ..., p (i + 3Ns-1 )of As such a pulse train of the s chaotic state are combined, becomes the pulse train independent Ns pieces of chaos are combined as shown in Figure 23. Ns is the number of clock light pulses in the delay step time T-1, and is an integer value of 1 or more.

  Due to such a combination of pulses, the pulse train of Ns chaotic states behaves unpredictably and randomly in the long term. Therefore, during the delay step time T-1, the optical output port P-MZ-1 The light output intensity of the output clock signal light pulse train from -cross behaves quite messy.

  Similarly, when the optical delay unit DT-2 is provided so that the delay step time T-2 becomes an arbitrary value equal to or longer than one step time, the optical output port of the Mach-Zehnder interference type optical intensity modulation unit MZ-2 The pulse train of the output clock signal light output from the P-MZ-2-cross is Qs chaos of p (i), p (i + 1), p (i + 2), ..., p (i + Qs-1). , P (i + Qs + 1), p (i + Qs + 2),..., P (i + 2Qs−1) are combined with a pulse train of states and p (i + Qs), p ( i + Qs + 1), p (i + Qs + 2),..., p (i + 2Qs-1) Qs pulse trains and p (i + 2Qs), p (i + 2Qs + 1), p (i + 2Qs + 2),. i + 3Qs As such a pulse train Qs number of chaotic state of 1) are combined, becomes the pulse train independent Qs pieces of chaos are combined. Qs is the number of clock light pulses in the delay step time T-2, and is an integer value of 1 or more.

  Due to such a combination of pulses, the pulse train of Qs chaotic states behaves unpredictably and randomly in the long term. Therefore, during the delay step time T-2, the optical output port P-MZ-2 The light output intensity of the output clock signal light pulse train from -cross behaves quite messy.

  However, in the output clock signal optical pulse train output from the optical output port P-MZ-1-cross of the Mach-Zehnder interference type optical intensity modulator MZ-1, the clock optical pulse at time step i and the clock optical pulse at time step i + Ns + 1 There remains a clear relationship as shown in FIG. That is, FIG. 15 shows the relationship between the light output intensity at time step i and the light output intensity at the next time step i + 1. Such a relationship is between time step i and time step i + Ns + 1. It also holds between.

  On the other hand, in the case of the output clock signal optical pulse train output from the optical output port P-MZ-2-cross of the Mach-Zehnder interference type optical intensity modulator MZ-2, the optical output of the time step i + Ns + 1 when viewed from the time step i. It is designed to be more cluttered with less predictable intensity. By driving the phase modulators R1-2 and L1-2 in the Mach-Zehnder interference type optical intensity modulator MZ-1 using the output clock signal optical pulse train from the optical output port P-MZ-2-cross, The light output of the Mach-Zehnder interference type light intensity modulation unit MZ-2 depends on the behavior of the light output intensity of the output clock signal light from the light output port P-MZ-1-cross of the Mach-Zehnder interference type light intensity modulation unit MZ-1. The randomness of the optical output intensity of the output clock signal light from the port P-MZ-2-cross can be convoluted.

  As a result, an optical circuit unit including the Mach-Zehnder interference type optical intensity modulation unit MZ-1, the optical demultiplexing unit SP-1, the optical delay unit DT-1, and the optical propagation delay difference providing unit DD-1 is provided. The relationship between the light intensities between adjacent pulses on the time step, as seen when driven alone, can be lost as shown in FIG. 24, and a random number sequence with increased randomness can be generated. Is possible. In this way, in this embodiment, it becomes possible to generate a random number sequence that is more random than in the third embodiment.

  In this embodiment, the optical output port P-MZ-1-cross is connected to the input of the optical demultiplexing unit SP-1, but the optical output port P-MZ-1-bar and the optical demultiplexing are connected. You may make it connect with the input of part SP-1. Further, the optical output port P-MZ-2-bar is connected to the input of the optical demultiplexing unit SP-2-1, and the optical output port P-MZ-2-cross and the optical demultiplexing unit SP-2-2 are connected. The input may be connected.

  In this embodiment, the output of the optical propagation delay difference providing unit DD-2-1 is connected to the optical input port PR1-2, but the optical propagation delay difference providing unit DD-2. -1 output is connected to the optical input port P-L1-2, and the optical propagation delay by the optical propagation delay difference providing unit DD-2-1 is provided among the outputs of the optical demultiplexing unit SP-2-2. The output that is not connected may be connected to the optical input port PR1-2.

  In this embodiment, the case where both the optical delay unit DT-1 and the optical delay unit DT-2 are provided is described. However, the optical delay unit DT-1 and the optical delay unit D are provided. Even when only one of -T-2 is provided, it is possible to respond to an ultrafast optical random number generation request, and to obtain an effect that random numbers with high randomness can be generated. The magnitude of the effect at this time is (when both the optical delay unit DT-1 and the optical delay unit DT-2 are provided)> (the optical delay unit D-T-2 is eliminated by eliminating the optical delay unit DT-2). (When only T-1 is provided) ≧ (when the optical delay unit DT-1 is eliminated and only the optical delay unit DT-2 is provided). FIG. 25 shows the configuration of a high-speed chaotic optical signal generating optical circuit in which the optical delay unit DT-2 is eliminated and only the optical delay unit DT-1 is provided. FIG. 26 shows the configuration of a high-speed chaotic optical signal generating optical circuit when only the delay unit DT-2 is provided.

  In this embodiment, RZ type clock signal light output from the same clock signal light source is demultiplexed in advance and input to the optical input ports P-MZ-1-1 and P-MZ-2-1. Alternatively, the RZ type clock signal light output from the first clock signal light source is input to the optical input port P-MZ-1-1 and is synchronized with the first clock signal light source. The RZ type clock signal light output from the second clock signal light source may be input to the optical input port P-MZ-2-1.

  In the present embodiment, the output signal light of the high-speed chaos optical signal generation optical circuit is output from two optical output ports P-MZ-1-cross and P-MZ- of the Mach-Zehnder interference type optical intensity modulator MZ-1. It may be obtained from any one of 1-bar. At this time, the light intensity at 100% output is set to 1 and the threshold is set to 0.5. If the light intensity of the output signal light is larger than the threshold, the value of the binarized signal is set to 1, and the output signal light If the light intensity is less than or equal to the threshold value, a binary random number sequence is obtained by performing binarization processing in which the value of the binarized signal is 0.

  The high-speed chaos optical signal generation optical circuit according to the first to fourth embodiments is configured by configuring the optical waveguide portion with a low-loss semiconductor waveguide and using the configuration as described above as the phase modulation unit. May be integrated with an optical semiconductor.

  In the high-speed chaotic optical signal generation optical circuits of the first to fourth embodiments, the optical waveguide portion is configured by a PLC (Planar Lightwave Circuit), and the above-described configuration is used as the phase modulation unit. The whole may be manufactured by a hybrid of PLC and optical semiconductor. Such an optical circuit is described in the document “T.Ito, et al.,“ Bit-rate and format conversion from 10-Gbit / s WDM channels to a 40-Gbit / s channel using a monolithic Sagnac interferometer integrated with parallelamplifier structure ”. , IEE Proc.-Optoelectron., Vol.151, No.1, p.41-45, February 2004, literature “Ikuo Ogawa et al.,“ PLC hybrid integrated semiconductor optical amplifier module ”, The Institute of Electronics, Information and Communication Engineers, IEICE technical report. EMD 102 (283), p.7-11, 2002-08-22 ”.

  In the high-speed chaotic optical signal generation optical circuit according to the first to fourth embodiments, a photonic crystal waveguide is used for the optical waveguide portion, and a quantum dot group is embedded in the core layer as a phase modulation unit. The entire structure may be integrated and manufactured using a configuration. Such optical circuits are described in the literature “H. Nakamura, Y. Sugimoto, K. Kanamoto, N. Ikeda, Y. Tanaka, Y. Nakamura, S. Ohkouchi, Y. Watanabe, K. Inoue, H. Ishikawa and K. Asakawa, “Ultra-fast photonic crystal / quantum dot all-optical switch for future photonic networks”, Optics Express, vol. 12, no. 26, p. 6606-6614, 2004 ”.

  The high-speed chaotic optical signal generation optical circuit according to the first to fourth embodiments is a planar optical circuit manufactured as an integrated optical circuit on a compound semiconductor substrate or a silicon planar substrate. Also good. A planar optical circuit fabricated as an integrated optical circuit on a silicon planar substrate is disclosed in the document “Seiichi Itabashi,“ Research and Development Trend of Silicon Photonics ”, NTT Technical Journal 2009.12, p.12-15, 2009”. Has been.

  The present invention is a technique for generating random numbers used in a computer that performs calculations such as device modeling, financial derivative calculation, and weather simulation, a random number used in a secret key sharing cryptographic system, or a random number used in quantum cryptographic communication. Can be applied to.

  MZ-1, MZ-2 ... Mach-Zehnder interference type light intensity modulation unit, SP-1, SP-2-1, SP-2-2 ... optical demultiplexing unit, DT-1, DT-2 ... Optical delay unit, DD-1, DD-2, DD-2-1 ... Optical propagation delay difference providing unit, P-MZ-1-1, P-R1, P-L1, P-R1 -1, P-L1-1, P-R1-2, P-L1-2, P-MZ-2-1, P-R2, P-L2 ... Optical input ports, R1, L1, R1-1, R1 -2, L1-1, L1-2, R2, L2 ... Phase modulator, P-MZ-1-cross, P-MZ-1-bar, P-MZ-2-cross, P-MZ-2-bar ... Optical output port, 100 to 109, 200 to 213, 216, 219, 221 to 230, 1010 to 1021 ... Optical waveguide, b1, b2 ... Multimode interference coupler, c1, 2 ... optical phase modulation control unit, d1, d2 ... phase adjustment portion, e1 ... light receiving portion.

Claims (5)

First Mach-Zehnder interference type light intensity modulation means MZ-1 for inputting RZ type clock signal light;
The RZ type clock signal output from one of the two optical output ports P-MZ-1-cross and P-MZ-1-bar of the first Mach-Zehnder interference type optical intensity modulation means MZ-1. A first optical demultiplexing means SP-1 for demultiplexing light into two systems;
In the first Mach-Zehnder interference type light intensity modulation means MZ-1, the two RZ type clock signal lights demultiplexed by the first light demultiplexing means SP-1 are used as clock signal lights for phase modulation control. A first optical waveguide leading to the first phase modulation means,
The first Mach-Zehnder interference type light intensity modulation means MZ-1
An optical input port P-MZ-1-1 for receiving the RZ type clock signal light;
Two first interference arms for transmitting the RZ type clock signal light input to the optical input port P-MZ-1-1;
The two optical output ports P-MZ-1-cross, P-MZ-1-bar provided at the ends of the two first interference arms;
One RZ type clock signal light provided on each of the two first interference arms and transmitted by the first interference arm is used as the light intensity of the RZ type clock signal light input from the first optical waveguide. The first phase modulation means R1 and L1 that perform phase modulation according to
The first phase modulation means R1, L1 are
A first optical interferometric type multiplexer that combines the clock signal light transmitted by the first interference arm and the clock signal light for phase modulation control, respectively, and demultiplexes the combined signal light into two systems. Branching means;
Two first optical waveguide arms for transmitting two systems of signal light output from the first optical interference type coupling means;
A second optical interference type multiplexing / branching unit that multiplexes the two signal lights transmitted by the two first optical waveguide arms and demultiplexes the combined signal light into two systems;
A first signal is provided on each of the two first optical waveguide arms, and phase-modulates the clock signal light transmitted by the first interference arm in accordance with the light intensity of the clock signal light for phase modulation control. Optical phase modulation control means,
A first phase adjusting means provided on at least one of the two first optical waveguide arms and capable of adjusting the phase of the signal light in accordance with the amount of injection current supplied from the outside;
Of the two optical output ports of the second optical interference type coupling / branching unit, the first optical receiving unit is configured to receive the signal light output from the one not connected to the first interference arm,
Further, two systems of RZ type clock signal light provided in the first optical waveguide and demultiplexed by the first optical demultiplexing means SP-1 reach the first phase modulating means R1 and L1. A delay corresponding to the difference in optical propagation delay until the first phase modulation means R1 and L1 among the two systems of RZ type clock signal light input to the first phase modulation means R1 and L1 is reached. First optical propagation delay difference providing means DD-1 for applying to the RZ type clock signal light having a longer optical propagation delay until
Of the two optical output ports of the second optical interference combining / branching means provided in each of the first phase modulation means R1 and L1, the phase modulation is performed from the one not connected to the first light receiving means. Clock signal light is output,
Obtaining output signal light from one of the two optical output ports P-MZ-1-cross and P-MZ-1-bar of the first Mach-Zehnder interference type light intensity modulating means MZ-1 High-speed chaotic optical signal generation optical circuit. The high-speed chaotic optical signal generating optical circuit according to claim 1,
Further, optical delay means DT provided in the first optical waveguide and imparting a predetermined delay to the two systems of RZ type clock signal light demultiplexed by the first optical demultiplexing means SP-1. -1. A high-speed chaotic optical signal generating optical circuit. The high-speed chaotic optical signal generating optical circuit according to claim 1,
Further, second Mach-Zehnder interference type light intensity modulation means MZ-2 for inputting the RZ type clock signal light,
The RZ type clock signal output from one of the two optical output ports P-MZ-2-cross and P-MZ-2-bar of the second Mach-Zehnder interference type optical intensity modulation means MZ-2. A second optical demultiplexing means SP-2-1 for demultiplexing light into two systems;
Of the two optical output ports P-MZ-2-cross and P-MZ-2-bar of the second Mach-Zehnder interference type optical intensity modulation means MZ-2, the second optical demultiplexing means SP-2 A third optical demultiplexing means SP-2-2 for demultiplexing the RZ type clock signal light output from the one not connected to -1 into two systems;
The second Mach-Zehnder interferometric light intensity modulating means MZ- is obtained by using the two RZ-type clock signal lights demultiplexed by the second optical demultiplexing means SP-2-1 as clock signal lights for phase modulation control. A second optical waveguide leading to second phase modulation means in 2;
The two RZ type clock signal lights demultiplexed by the third optical demultiplexing means SP-2-2 are used as the phase modulation control clock signal lights, and the first Mach-Zehnder interference type optical intensity modulation means MZ- A third optical waveguide leading to third phase modulation means in 1,
The first Mach-Zehnder interference type light intensity modulation means MZ-1
Further, instead of the first phase modulation means R1 and L1, one RZ type clock signal light provided on each of the two first interference arms and transmitted by the first interference arm is supplied to the first phase modulation means R1 and L1. First phase modulation means R1-1 and L1-1 that perform phase modulation according to the light intensity of the RZ type clock signal light input from one optical waveguide;
RZ type clock signal light that is provided one by one in the two first interference arms behind the first phase modulation means R1-1 and L1-1 and transmitted by the first interference arm, The third phase modulation means R1-2 and L1-2 that perform phase modulation according to the light intensity of the RZ type clock signal light input from the third optical waveguide;
The second Mach-Zehnder interference type light intensity modulation means MZ-2 includes:
An optical input port P-MZ-2-1 for receiving the RZ type clock signal light;
Two second interference arms that transmit the RZ type clock signal light input to the optical input port P-MZ-2-1;
The two optical output ports P-MZ-2-cross, P-MZ-2-bar provided at the ends of the two second interference arms;
One RZ type clock signal light provided on each of the two second interference arms and transmitted by the second interference arm is used as the light intensity of the RZ type clock signal light input from the second optical waveguide. The second phase modulation means R2 and L2 that perform phase modulation according to
The first phase modulation means R1-1 and L1-1 are:
The clock signal light transmitted by the first interference arm and the clock signal light for phase modulation control input from the first optical waveguide are combined to divide the combined signal light into two systems. First optical interference type merging / branching means to wave;
Two first optical waveguide arms for transmitting two systems of signal light output from the first optical interference type coupling means;
A second optical interference type multiplexing / branching unit that multiplexes the two signal lights transmitted by the two first optical waveguide arms and demultiplexes the combined signal light into two systems;
One of the two first optical waveguide arms, and the clock signal light transmitted from the first interference arm for clock signal light for phase modulation control input from the first optical waveguide. First optical phase modulation control means for performing phase modulation according to intensity;
A first phase adjusting means provided on at least one of the two first optical waveguide arms and capable of adjusting the phase of the signal light in accordance with the amount of injection current supplied from the outside;
Of the two optical output ports of the second optical interference type coupling / branching unit, the first optical receiving unit is configured to receive the signal light output from the one not connected to the first interference arm,
The second phase modulation means R2, L2 are
The clock signal light transmitted by the second interference arm and the clock signal light for phase modulation control input from the second optical waveguide are combined to divide the combined signal light into two systems. A third optical interference type merging / branching means to wave;
Two second optical waveguide arms that transmit the two signal light beams output from the third optical interference type combining / branching means;
A fourth optical interference type multiplexing / branching unit that multiplexes two systems of signal light transmitted by the two second optical waveguide arms and demultiplexes the combined signal light into two systems;
The clock signal light for phase modulation control that is provided to the two second optical waveguide arms, and that is supplied from the second optical waveguide to the clock signal light transmitted by the second interference arm. Second optical phase modulation control means for phase modulation according to the intensity;
A second phase adjusting means provided on at least one of the two second optical waveguide arms and capable of adjusting the phase of the signal light in accordance with the amount of injection current supplied from the outside;
Of the two optical output ports of the fourth optical interference type merging / branching means, the second light receiving means for receiving the signal light output from the one not connected to the second interference arm,
The third phase modulation means R1-2 and L1-2 are:
Two third optical waveguide arms each;
One of the two third optical waveguide arms is provided, and the clock signal light transmitted from the first interference arm is transmitted from the third optical waveguide to the phase modulation control clock signal light. Third optical phase modulation control means for performing phase modulation according to the intensity;
A third phase adjusting means provided on at least one of the two third optical waveguide arms and capable of adjusting the phase of the signal light in accordance with the amount of injection current supplied from the outside;
The clock signal light transmitted by the first interference arm and the clock signal light transmitted by one of the two third optical waveguide arms are combined, and the combined signal light is divided into two systems. A fifth optical interference type merging / branching means for demultiplexing;
A signal obtained by combining the clock signal light for phase modulation control input from the third optical waveguide and the clock signal light transmitted by the other of the two third optical waveguide arms, and combining them. A sixth optical interference combining / branching means for demultiplexing the light into two systems;
Of the two optical output ports of the sixth optical interference type merging / branching means, a third light receiving means for receiving the signal light output from the one not connected to the first interference arm,
The first optical propagation delay difference applying unit DD-1 is configured to convert the two systems of RZ type clock signal light demultiplexed by the first optical demultiplexing unit SP-1 into the first phase modulating unit R1. −1, a delay corresponding to a difference in optical propagation delay until reaching L1-1 is set to be one of the two RZ-type clock signal lights input to the first phase modulation means R1-1 and L1-1. The RZ type clock signal light having a longer optical propagation delay until reaching the first phase modulation means R1-1, L1-1,
Further, two RZ-type clock signal lights provided in the second optical waveguide and demultiplexed by the second optical demultiplexing means SP-2-1 are supplied to the second phase modulating means R2 and L2. A delay corresponding to the difference in optical propagation delay until reaching the second phase modulation means R2 and L2 out of the two systems of RZ type clock signal light inputted to the second phase modulation means R2 and L2. Second optical propagation delay difference providing means DD-2 for imparting to the RZ-type clock signal light having a longer light propagation delay until arrival;
Two systems of RZ type clock signal light provided in the third optical waveguide and demultiplexed by the third optical demultiplexing means SP-2-2 are used as the third phase modulating means R1-2, L1-. The delay corresponding to the difference in optical propagation delay until reaching 2 is set to the third phase of the two RZ-type clock signal lights input to the third phase modulation means R1-2 and L1-2. A third optical propagation delay difference providing unit DD-2-1 for applying to the RZ type clock signal light having a longer optical propagation delay until reaching the modulating unit R1-2, L1-2,
Of the two optical output ports of the second optical interference type coupling / branching unit provided in each of the first phase modulation units R1-1 and L1-1, the one not connected to the first light receiving unit The phase-modulated clock signal light is output from the second optical output port of the fourth optical interference type combining / branching means provided in each of the second phase modulation means R2 and L2. The phase-modulated clock signal light is output from the one not connected to the light receiving means, and the sixth optical interference type coupling / branching provided in each of the third phase modulation means R1-2 and L1-2 The phase-modulated clock signal light is output from the one not connected to the third optical waveguide arm among the two optical output ports of the means,
Obtaining output signal light from one of the two optical output ports P-MZ-1-cross and P-MZ-1-bar of the first Mach-Zehnder interference type light intensity modulating means MZ-1 High-speed chaotic optical signal generation optical circuit. The high-speed chaotic optical signal generating optical circuit according to claim 3,
Further, a delay of a predetermined delay time T-1 is given to each of the two systems of RZ type clock signal light provided in the first optical waveguide and demultiplexed by the first optical demultiplexing means SP-1. Optical delay means DT-1,
A predetermined delay time T-2 (T-1 ≠ T) is added to each of the two RZ-type clock signal lights provided in the second optical waveguide and demultiplexed by the second optical demultiplexing means SP-2-1. A high-speed chaotic optical signal generating optical circuit comprising at least one of optical delay means DT-2 for providing a delay of T-2). The high-speed chaotic optical signal generation optical circuit according to any one of claims 1 to 4,
The optical phase modulation control means includes a semiconductor optical amplifier having a property that a refractive index changes according to the light intensity of the clock signal light for phase modulation control, and according to the light intensity of the clock signal light for phase modulation control. Optical waveguide structure including quantum dot layer having property of changing refractive index, semiconductor EA optical modulator in constant voltage driving state having property of changing refractive index in accordance with light intensity of clock signal light for phase modulation control A high-speed chaotic optical signal generating optical circuit comprising:

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