CN112653514B

CN112653514B - Multi-wavelength light source generator and method of generating multi-wavelength light source

Info

Publication number: CN112653514B
Application number: CN201910961478.3A
Authority: CN
Inventors: 桂成程; 宋小鹿; 付生猛; 周恒�
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-10-11
Filing date: 2019-10-11
Publication date: 2022-07-22
Anticipated expiration: 2039-10-11
Also published as: CN112653514A

Abstract

A multi-wavelength light source generator and a method of generating a multi-wavelength light source are provided. The multi-wavelength light source generator includes a laser, a microcavity, and an ion generator. Wherein, the ion generator is used for doping rare earth element ions into the microcavity. The laser is used for outputting a single-wavelength light beam to the microcavity. The microcavity is used for enabling the light beam to generate a Kerr effect to generate a multi-wavelength light source, and the rare earth element ions are used for amplifying the multi-wavelength light source and then outputting the multi-wavelength light source. By doping the rare earth element ions into the microcavity, the power of the multi-wavelength light beam generated in the microcavity due to the kerr effect can be amplified under the action of the rare earth element ions, that is, the output power of the multi-wavelength light source can be improved.

Description

Multi-wavelength light source generator and method of generating multi-wavelength light source

Technical Field

The present application relates to the field of optical communications, and more particularly, to a multi-wavelength light source generator and a method of generating a multi-wavelength light source in the field of optical communications.

Background

With the development of the information age, the demand of people on data transmission capacity is higher and higher, and in the traditional single-channel transmission mode, the demand of large-capacity information transmission cannot be met by carrying high-order modulation signals by a single channel.

Therefore, a plurality of channels can be used for parallel transmission, each channel is loaded with a high-order modulation signal, and the communication capacity of the whole link is greatly improved.

To realize parallel transmission of multiple channels, a light source with multiple wavelengths is required. Currently, there is known a method of providing a multi-wavelength light source using the kerr effect, that is, making a single light source simultaneously generate optical frequency combs (i.e., kerr optical combs) of a plurality of channels based on the kerr nonlinear effect of a single micro-ring resonator. The technology can realize accurate control of frequency interval and realize high Optical Signal Noise Ratio (OSNR).

The output power of the current Kerr optical comb generation device is low, and the requirement of an optical link cannot be met.

Disclosure of Invention

Provided are a multi-wavelength light source generator and a method of generating a multi-wavelength light source, which can increase the power of an output multi-wavelength light source.

In a first aspect, an embodiment of the present application provides a multi-wavelength light source generator, including a first laser, a microcavity, and an ion generator, where the ion generator is configured to dope rare-earth ions into the microcavity; the first laser is used for outputting a first light beam to the microcavity, and the first light beam is a single-wavelength light beam; the microcavity is used for enabling the first light beam to generate a Kerr effect to generate a multi-wavelength light source, and the rare earth element ions are used for amplifying the multi-wavelength light source and then outputting the multi-wavelength light source.

According to the multi-wavelength light source generator provided by the application, the rare earth element ions are doped into the micro-cavity, so that the power of the multi-wavelength light beam generated in the micro-cavity due to the Kerr effect can be amplified under the action of the rare earth element ions, namely, the output power of the multi-wavelength light source can be improved.

The multi-wavelength light source may also be referred to as a kerr comb.

Specifically, the rare earth element ions include erbium ions. Alternatively, optionally, the species of rare-earth element ions doped by the ion generator into the microcavity correspond to the wavelength (or frequency) of the first light beam output by the first laser. For example, when the wavelength of the first light beam is a C band or an L band, the rare-earth element ions include erbium ions. Wherein, the C band can also be referred to as C band (conventional band) conventional band, i.e. the wavelength range is 1530 and 1565 nanometers (nm). The L band may also be referred to as L band (long wavelength band) long wavelength band, i.e., the wavelength range is 1565-.

It should be understood that the above listed mapping relationships are merely exemplary, and the present application is not limited thereto, as long as it is satisfied that the rare earth element ions can have a power amplification effect on the light beam of the corresponding wavelength band.

Optionally, the ion generator comprises: a first medium and a second laser, wherein a constituent substance of the first medium includes the rare-earth element ion, and the first medium is disposed within the microcavity; the second laser is used for irradiating a second light beam to the first medium. For example, the first medium comprises erbium doped fiber.

Wherein the constituent material of the first medium includes the rare earth element ion may be understood that the constituent element of the first medium includes an element corresponding to the rare earth element ion. Alternatively, the constituent material of the first medium includes the rare earth element ions, which is understood to mean that the first medium releases the rare earth element ions after being irradiated with light.

By providing the first medium containing the rare earth element in the microcavity, the first medium can be illuminated to easily generate rare earth element ions in the microcavity, thereby improving the practicability of the multi-wavelength light source generator.

Optionally, the ion generator further comprises: a first filter for filtering the second beam before it impinges on the first medium. By filtering the second light beam, noise in the second light beam (for example, light having a different wavelength band from the second light beam, or phase noise of the laser itself) can be eliminated, thereby reducing noise of the multi-wavelength light source generated by the multi-wavelength light source generator of the present application.

Optionally, the microcavity includes a waveguide and a cavity, and the first light beam is input to the waveguide from a first light-passing port of the waveguide and coupled from the waveguide to the cavity, and the second light beam is input to the waveguide from a second light-passing port of the waveguide and coupled from the waveguide to the cavity.

"outputting a first light beam towards the microcavity" may be understood as irradiating a first light beam towards a waveguide of the microcavity, which is in turn coupled from the waveguide into the cavity of the microcavity. "irradiating the first medium with the second light beam" may be understood as irradiating the waveguide of the microcavity with the second light beam, which is in turn coupled from the waveguide into the cavity of the microcavity and onto the first medium.

It should be understood that the above-listed structures of the microcavity are merely exemplary, and the present application is not limited thereto, and for example, the light beam may be directly irradiated into the cavity of the microcavity without waveguide coupling.

The first light beam and the second light beam are input into the waveguide through different light-passing ports.

In the application, when the second light beam is input into the microcavity, the microcavity can be heated, and the heat effect in the microcavity is compensated, so that the stable multi-wavelength light source can be generated. In the present application, the second light beam can be used as the heat release source of the thermal effect, so that the overhead caused by additionally configuring the heat release source can be reduced, the cost and the structural complexity of the multi-wavelength light source generator of the present application can be reduced, and the practicability of the multi-wavelength light source generator of the present application can be further improved.

Optionally, the first light passing port is disposed opposite to the second light passing port. Specifically, the first light admission port and the second light admission port are disposed so as to face each other, that is, so that the first light flux entering the microcavity from the first light admission port and the second light flux entering the microcavity from the second light admission port can be propagated in opposite directions to each other, in such a manner that the positions of the first light admission port and the second light admission port on the microcavity are opposed to each other.

Optionally, the multi-wavelength light source generator further comprises: a controller for controlling the concentration of the rare earth element ions in the micro-cavity. By configuring the controller, the multi-wavelength light source generator can adjust the concentration of the rare earth element ions in the micro-cavity, thereby realizing the adjustment of the power of the multi-wavelength light source output from the micro-cavity.

Optionally, the multi-wavelength light source generator further comprises: a detector for detecting power of the multi-wavelength light source output from the microcavity; and the controller is specifically used for controlling the concentration of the rare earth element ions in the microcavity according to the power of the multi-wavelength light source so as to enable the power of the multi-wavelength light source to meet a preset condition.

By arranging the detector and adjusting the concentration of the rare earth element ions based on the power of the multi-wavelength light source monitored by the detector, the accuracy and precision of the adjustment of the power of the multi-wavelength light source output from the micro cavity can be realized, and the practicability of the multi-wavelength light source generator is further improved.

Optionally, the controller is specifically configured to adjust at least one of the following parameters to control the concentration of the rare earth element ion within the micro-cavity: irradiating the substance which releases the rare earth element ions for a time when the second beam is irradiated to the first substance; a spot size of a beam irradiating a substance which releases the rare earth element ion, that is, a spot size of the second beam, or a spot size of the second beam irradiated on the first substance; or, the power of the beam irradiating the substance which releases the rare earth element ion, that is, the power of the second beam, or the power of the second beam irradiating on the first substance.

Optionally, the multi-wavelength light source generator further comprises: a second filter for filtering the first light beam before the first light beam enters the microcavity. By filtering the first light beam, the noise in the first light beam can be eliminated, and the noise of the multi-wavelength light source generated by the multi-wavelength light source generator can be reduced.

Optionally, the multi-wavelength light source generator further comprises: and the power amplifier is used for amplifying the power of the first light beam before the first light beam is emitted into the microcavity. Thus, the power of the multi-wavelength light source generated by the multi-wavelength light source generator of the present application can be further increased.

In a second aspect, embodiments of the present application provide a method of generating a multi-wavelength light source. The method comprises the following steps: doping rare earth element ions into the microcavity; and irradiating a first light beam to the microcavity, wherein the first light beam is a single-wavelength light beam, so that the first light beam generates a Kerr effect to generate a multi-wavelength light source, the multi-wavelength light source is output after being amplified, and the amplification is performed by using the rare earth element ions.

According to the method for generating the multi-wavelength light source, the rare earth element ions are doped into the micro-cavity, so that the power of the multi-wavelength light beam generated in the micro-cavity due to the Kerr effect can be amplified under the action of the rare earth element ions.

Optionally, the species of the rare earth element ions doped into the microcavity by the ion generator corresponds to an operating band (or frequency range) of the first light beam output by the first laser. For example, when the wavelength of the first light beam is a C band or an L band, the rare-earth element ions include erbium ions. It should be understood that the mapping relationship listed above is merely an exemplary illustration, and the present application is not limited thereto as long as it satisfies that the rare earth element ions can have a power amplification effect on the light beam of the corresponding wavelength band.

Optionally, the doping rare earth element ions into the microcavity includes: and irradiating the second light beam to a first medium arranged in the micro-cavity, wherein the composition matter of the first medium comprises the rare earth element ions. For example, the first medium comprises erbium doped fiber. Wherein the constituent material of the first medium includes the rare earth element ion may be understood that the constituent element of the first medium includes an element corresponding to the rare earth element ion. Alternatively, the constituent material of the first medium includes the rare earth element ions, which is understood to mean that the first medium releases the rare earth element ions after being irradiated with light.

By providing the first medium including a rare earth element in the microcavity, it is possible to easily generate rare earth element ions in the microcavity by illuminating the first medium, thereby further improving the practicality of the method of generating a multiwavelength light source of the present application.

Optionally, the method further comprises: filtering the second beam of light before it impinges on the first medium. The filtering can eliminate noise in the second beam, thereby reducing noise of the multi-wavelength light source.

Optionally, the irradiating the first beam to the microcavity comprises: irradiating the first light beam into the microcavity through a first light transmitting port on the microcavity; the irradiating a second beam of light to a first medium disposed within the microcavity comprises: and irradiating the second light beam to the first medium through a second light-passing port on the microcavity. That is, the first light beam and the second light beam are irradiated into the microcavity through different light-passing ports.

When the second light beam is irradiated into the microcavity, the microcavity can be heated, the heat effect in the microcavity is compensated, so that a stable multi-wavelength light source is generated, the second light beam is used as a heat release source of the heat effect, the overhead caused by the heat release source additionally arranged can be reduced, the cost and the structural complexity of the multi-wavelength light source generator are reduced, and the practicability of the method for generating the multi-wavelength light source is further improved.

Optionally, the first light passing port and the second light passing port are configured oppositely. Specifically, the first light admission port and the second light admission port are disposed so as to face each other, that is, so that the first light flux entering the microcavity from the first light admission port and the second light flux entering the microcavity from the second light admission port can be propagated in opposite directions to each other, in such a manner that the positions of the first light admission port and the second light admission port on the microcavity are opposed to each other.

Optionally, the method further comprises: adjusting a concentration of ions of the rare earth element within the microcavity.

According to the method for generating the multi-wavelength light source, the power of the multi-wavelength light source output from the micro cavity can be adjusted by adjusting the concentration of the rare earth element ions in the micro cavity.

Optionally, the method further comprises: detecting power of a multi-wavelength light source output from the microcavity; and said adjusting a concentration of ions of said rare earth element within said microcavity comprises: and adjusting the concentration of the ions of the rare earth elements in the microcavity according to the detected power of the multi-wavelength light source output from the microcavity so that the power of the multi-wavelength light source output from the microcavity meets a preset condition.

By adjusting the concentration of the rare earth element ions based on the monitored power of the multi-wavelength light source, the accuracy and precision of the adjustment of the power of the multi-wavelength light source output from the micro-cavity can be achieved, thereby further improving the practicality of the method of generating a multi-wavelength light source of the present application. The adjustment of the concentration of the rare earth element ions in the micro-cavity may be performed using one or more of the parameters described in the implementation manners of the first aspect, which are not described herein again.

Optionally, the method further comprises: filtering the first light beam before the first light beam is input into the microcavity. The filtering can eliminate noise in the first beam, thereby reducing noise of the multi-wavelength light source.

Optionally, the method further comprises: power amplifying the first beam of light before the first beam of light is input into the microcavity. Thus, the power of the multi-wavelength light source can be further increased.

In a third aspect, an optical transmission apparatus is provided, which includes a multi-wavelength light source generator, a wavelength division demultiplexer, a modulator, and a wavelength division multiplexer in the first aspect and possible implementations thereof, where the wavelength division demultiplexer is configured to separate multi-wavelength light beams generated by the multi-wavelength light source generator and then input the separated multi-wavelength light beams to the corresponding modulators, the modulators are configured to load data to be transmitted onto corresponding wavelengths, and the wavelength division multiplexer combines a plurality of wavelengths loaded with data and transmits the combined wavelengths through an optical fiber.

Drawings

Fig. 1 is a schematic configuration diagram of an example of a multiwavelength light source generator according to the present application.

Fig. 2 is a schematic configuration diagram of another example of the multi-wavelength light source generator according to the present application.

FIG. 3 is a schematic view of a microcavity of the present application.

Fig. 4 is a schematic diagram of an example of the ion generating apparatus according to the present application.

Fig. 5 is a schematic configuration diagram of still another example of the multi-wavelength light source generator according to the present application.

Fig. 6 is a comparison of simulated spectral lines of kerr optical combs generated based on prior art schemes and based on the schemes provided herein, respectively.

Fig. 7 is a schematic flowchart of an example of the method of generating a multiwavelength light source according to the present application.

Fig. 8 is a schematic structural view of a light emitting device of the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

Fig. 1 shows a schematic block diagram of a multi-wavelength light source generator 100 of the present application. As shown in fig. 1, the multi-wavelength light source generator 100 includes: a microcavity 110, an ion generator 120, and a laser 130. The laser 130 (i.e., an example of the first laser) may also be referred to as a light source 130, and emits a light beam (hereinafter, referred to as a light beam 135 for ease of understanding and distinction). Wherein the beam 135 comprises a single wavelength beam, i.e., the laser 130 is used to generate the single wavelength beam.

The output port of the laser 130 is connected to the input port 1101 of the microcavity 110, i.e., the beam 135 output from the laser 130 (specifically, the output port of the laser 130) can be input to the microcavity 110 via the input port 1101.

Optionally, as shown in fig. 2, the multi-wavelength light source generator 100 further includes a circulator 191. That is, the output port of the laser 130 is connected to the input port 1101 of the microcavity 110 via the circulator 191. Specifically, the output port of the laser 130 is connected to the port 1911 of the circulator 191, and the port 1912 of the circulator 191 is connected to the input port 1101 of the microcavity 110. The light beam output from the port 1911 of the circulator 191 can be output through the port 1912 of the circulator 191. However, the light beam input from the port 1912 of the circulator 191 cannot be output through the port 1911 of the circulator 191. Therefore, the light beam 135 output from the laser 130 can be input to the microcavity 110 (for example, a waveguide of the microcavity 110 described later) through the circulator 191, but the light beam emitted from the microcavity 110 (for example, a light beam generated by reflecting the light beam 135 in the microcavity) cannot enter the laser 130 through the circulator 191, and thus the laser 130 can be prevented from being damaged.

It should be understood that the above-listed scheme for disposing the circulator 191 is only an example of the present application, and the present application is not limited thereto. The circulator 191 may not be provided. Alternatively, in order to prevent the laser 130 from being damaged by receiving the irradiation of the light beam emitted from the micro-cavity 110, a one-way light-passing device may be provided at the output port of the laser 130. That is, the one-way light-passing device can pass a light beam emitted from the laser 130 and can block a light beam irradiated to the laser 130.

The structure and function of the micro-cavity 110 will be described in detail below.

In this application, microcavity refers to an optical resonator with a high Quality factor (Quality factor, generally denoted by Q). The light wave is totally reflected at the interface of the micro-cavity, thereby generating a resonance mode and enhancing the light intensity. That is, a microcavity, which may also be referred to as an optical microcavity, is an optical resonator that is capable of confining an optical field in a region on the order of microns. It uses reflection, scattering or diffraction at the interface of the material with discontinuous dielectric constant to limit the light energy to oscillate back and forth in a small area, thereby increasing the photon lifetime and reducing the number of optical field modes.

By way of example, and not limitation, the microcavities of the present application include, but are not limited to, the following types of microcavities.

Type 1: echo wall type micro-cavity

The light wave forms resonance along a ring loop in the cavity, and forms strong limitation on light through a total reflection interface formed by a high-refractive-index medium in the cavity and an external low-refractive-index medium. According to the shape of the cavity, the echo wall type microcavity cavity can be divided into an annular cavity and a polygonal cavity. Wherein, the annular cavity comprises microspheres, micro disks, micro rings, micro columns and the like. Polygonal cavities include triangular, quadrilateral, and even hexagonal cavities.

By means of the circular microcavity, we can easily understand the whispering gallery modes using the theory of total reflection. As shown in fig. 3, the ray propagates from point a along the microcavity edge at an angle of incidence χ. Due to the rotational symmetry, the light rays can be continuously totally reflected at the same incident angle in the cavity. After a finite number of reflections, the ray will return to the origin a. When the phase matching condition is satisfied, equally spaced resonant modes are formed in the resonant cavity, and such modes are called whispering gallery modes.

In recent years, microfabrication and nanotechnology have been developed to make it possible to fabricate optical microresonator of various specific shapes based on various natural and synthetic materials. The integrated micro-ring, micro-disk resonant cavity and optical crystal defect microcavity are usually fabricated on a substrate by using a relatively abundant integrated circuit micro-machining process, and are not described herein again.

Type 2: Fabry-Perot microcavity

The active region is mostly quantum well material, the upper and lower sides of the active region are respectively composed of reflectors with extremely high reflectivity, and light is reflected in the two reflectors to form resonance. Most of the mirrors of the fabry-perot microcavity are Distributed Bragg Reflectors (DBRs).

Type 3: photonic crystal microcavity

A photonic crystal is a material with a periodic dielectric constant through which only light of a specific wavelength passes due to the existence of a photonic band gap. When a defect is introduced into the periodic structure to form a microcavity, a corresponding defect state energy level appears in the photonic band gap, and light with a frequency at the defect energy level propagates along the defect or oscillates locally in the photonic crystal, so that the distribution of the optical field can be controlled. This cavity is a defect introduced manually in the desired structure, its mode volume being very small. The shape and the harmonic wavelength of the defect cavity are accurately controlled through a micro-nano processing technology. Therefore, the method is widely applied to the fields of lasers, filters and the like.

In the present application, the light beam 135 is capable of generating a kerr effect (or kerr nonlinear effect) within the microcavity 110 to produce a multi-channel optical frequency comb (such as the kerr comb 137 in fig. 2), an example of a multi-wavelength light source. A kerr optical comb refers to a spectrum spectrally composed of a series of frequency components that are uniformly spaced and have coherently stable phase relationships. The kerr effect means: a substance placed in an electric field exhibits anisotropy because its molecules are oriented (deflected) by the action of an electric force, resulting in birefringence, i.e., the refractive power of the substance to light differs in two different directions. The optical frequency comb may also be referred to as a kerr optical frequency comb, a kerr optical comb, an optical frequency comb, or a soliton mode-locked kerr optical comb. For simplicity of description, a kerr optical comb is used subsequently.

Q is one of the most fundamental physical quantities of an optical mode (which may also be referred to as the transmission mode of light) and is used to characterize how fast energy decays in a resonant cavity or its ability to store energy. For example, Q can be calculated by the following formula:

where U is the total energy stored in the cavity, P ═ dU/dt is the energy lost per unit time, i.e. the dissipated power, and ω is the circular frequency of the optical field. ω 2 pi υ, where υ is the optical field frequency.

The loss a of a conventional optical microcavity results from two parts. Some of the loss is the transmission loss (a0) of the microcavity itself, which is the intrinsic attenuation caused by absorption, scattering, etc. received during the transmission of the optical field in the cavity. Another part is microcavity coupling loss (κ), which refers to the coupling-out of the intracavity optical field, i.e.: a ═ a0+ κ, where a and κ both contribute to the microcavity load quality factor, i.e.: q is inversely related (or inversely proportional) to a.

In practical applications, it is desirable to have microcavities with higher Q values, and thus a0 and κ as small as possible. However, if the k value is very small, only a very small portion of the optical comb power is output outside the microcavity after the kerr optical comb is generated in the cavity.

To increase the output power of the multi-wavelength light source (or the coupling loss κ of the microcavity 110) while ensuring that the microcavity 110 has a higher Q value, the multi-wavelength light source generator 100 of the present application includes an ion generator 120 for doping the microcavity 110 with rare-earth ions. The ion generator 120 is capable of releasing rare earth element ions into the micro-cavity 110. Wherein the rare earth ions are capable of amplifying (or power amplifying) the kerr comb 137.

Specifically, rare earth elements (or rare earth elements) have a large energy difference between a metastable state and a ground state. For example, the energy difference between the metastable and ground states of erbium ions corresponds to the energy of 1550nm photons. Thus, the kerr optical comb 137 can be amplified by the stimulated amplification principle of light (or, the stimulated radiation or stimulated scattering principle). I.e. to increase the output power of the output multi-wavelength light source.

For example, the amplification of the kerr optical comb 137 may be achieved by irradiating the microcavity 110 with pump light whose energy is absorbed by the rare-earth element ions to transition the rare-earth element ions to a higher energy level and transferred to the energy of the kerr optical comb 137 by stimulated emission between the energy levels.

As described above, the energy difference between the metastable state and the ground state differs for different rare earth element ions. Accordingly, the corresponding rare earth element ions may be selected based on the wavelength of the light to be amplified, for example, erbium ions may be used as the ions that the ion generator 120 can release into the microcavity 110 when amplification of C-band or L-band light is required (e.g., the light beam 135 is C-band or L-band light). For another example, when the light beam 135 has a wavelength of 1300nm or 1300nm, praseodymium ions can be used as the ions that can be released into the micro-cavity 110 by the ion generator 120. For another example, when the light with a wavelength of 1400nm needs to be amplified, or when the light beam 135 has a wavelength of 1400nm, thulium ions may be used as the ions that the ion generator 120 can release into the microcavity 110.

Fig. 2 shows an example of the structure of the microcavity 110 according to the present invention. As shown in fig. 2, the microcavity 110 includes a cavity and a waveguide. The light beams 135 and 145 are input to the waveguide from both ends of the waveguide and coupled into the cavity through the waveguide, respectively, and the kerr effect occurs.

As shown in fig. 2, port 1923 of circulator 192 may be used as an output port of the kerr optical comb 137. Alternatively, the fiber can be extracted from the waveguide as an output port of the kerr optical comb 137.

Fig. 4 illustrates one implementation of the ion generator 120 of the present application. As shown in fig. 4, the ion generator 120 includes a substance 121 and a laser 140 (not shown in fig. 4) disposed within the microcavity 110. A substance 121 (i.e., an example of a first substance) is placed in the microcavity. The substance 121 is a substance capable of releasing rare earth element ions under irradiation by a beam 145 (i.e., a beam emitted from the laser 140 shown in fig. 2). Alternatively, the constituent elements of the substance 121 include rare earth elements.

By way of example and not limitation, the substance 121 comprises a rare earth doped fiber, i.e., a silica fiber doped with a rare earth element. By way of example and not limitation, erbium doped fiber may be used as substance 121 when beam 135 is C-band or L-band light. When the wavelength of the light beam 135 is 1400nm, a thulium doped fiber may be used as the substance 121. Praseodymium doped fiber may be used as the substance 121 when the wavelength of the light beam 135 is 1300 nm.

The laser 140 emits a beam (denoted as beam 145) that excites the substance 121 to release the rare earth element.

The output port of the laser 140 is connected to the input port 1102 of the microcavity 110 (e.g., a waveguide of the microcavity 110). I.e., the beam 145 output from the laser 40 (specifically, the output port of the laser 140) can be input to the microcavity 110 via the input port 1102.

Optionally, as shown in fig. 2, the multi-wavelength light source generator 100 further includes a circulator 192. That is, the output port of the laser 140 is connected to the input port 1102 of the microcavity 110 via the circulator 192. Specifically, the output port of the laser 140 is connected to the port 1921 of the circulator 192, and the port 1922 of the circulator 192 is connected to the input port 1102 of the microcavity 110.

The circulator 192 is similar to the circulator 191 in fig. 2, and thus, the description thereof is omitted. The beam 145 output from the laser 140 can be input to the microcavity 110 via the circulator 192, but the beam emitted from the microcavity 110 cannot enter the laser 140 via the circulator 192, so that damage to the laser 140 can be avoided.

It should be understood that the above-listed embodiments of the circulator 192 are only examples of the present application, and the present application is not limited thereto. Alternatively, a one-way light-passing device may be provided at the output port of the laser 140 to prevent the laser 140 from being damaged.

By way of example and not limitation, the input port 1102 of the microcavity 110 and the input port 1101 of the microcavity 110 may be the same port. That is, light emitted from the laser 140 and the laser 130 may be input to the microcavity 110 through the same port at different times, respectively. Alternatively, as shown in FIG. 2, the input port 1102 of the microcavity 110 and the input port 1101 of the microcavity 110 may be different ports.

Taking the case of doping erbium ions in the microcavity as an example, but not by way of limitation, in the present application, a high-power laser beam is first used to cut a whispering gallery cavity microcolumn on a silicon dioxide (SiO2) cylinder rotating at a high speed, so as to form a microcavity structure; placing the high-concentration erbium-doped fiber on the surface of the micro-cavity structure of the echo wall by using a clamp, wherein the absorption coefficient of the high-concentration erbium-doped fiber at 1530nm is more than 100 dB/m; meanwhile, the spot size of the high-power laser beam at the microcavity structure is increased, then the output power of the laser is increased, the echo wall microcavity structure is polished, and meanwhile the erbium-doped fiber is melted and transferred to the high-speed rotating echo wall microcavity structure; and controlling the actual erbium-doped concentration in the echo wall micro-cavity by selecting the times of repeating the steps, thereby controlling the actual gain value of the erbium-doped micro-cavity.

In the present application, the laser 140 may have, in addition to the above-mentioned beam 145 for emitting the rare-earth element ions exciting the substance 121, one or more of the following functions:

function 1: for emitting the pump light. That is, the wavelength of the beam 145 corresponds to the wavelength of the pump light.

Function 2: for heating the microcavity 110 to compensate for thermal effects of the microcavity 110 itself, so that the beam 135 generated by the laser 130 can generate a stable kerr comb under kerr effect.

The cost and the structural complexity of the multi-wavelength light source generator can be reduced by providing multiple functions through one device.

When the laser 140 has the above-described functions 1 and 2, the input port 1102 of the microcavity 110 (specifically, the waveguide of the microcavity 110) and the input port 1101 of the microcavity 110 may be arranged to face each other, that is, the propagation directions of the light beam 135 and the light beam 145 are opposite to each other, so that an additional secondary influence on the optical comb is prevented.

It should be understood that the above-listed implementation of the ion generator 120 is merely an exemplary illustration, and the present application is not limited thereto. For example, a laser for emitting pump light may be additionally configured. Alternatively, a heat source (e.g., a laser) for heating the micro-cavity 110 may be additionally provided. Alternatively, other devices or devices capable of releasing rare earth ions into the microcavity 110 can be used as the ion generator 120.

Optionally, as shown in fig. 2, in the present application, a filter 150 may also be provided. The filter 150 is used to remove noise from the beam 135 before the beam 135 is injected into the microcavity 110.

Optionally, as shown in fig. 2, in the present application, a filter 160 may also be provided. The filter 160 is used to remove noise in the beam 145 before the beam 145 is injected into the microcavity 110.

Optionally, as shown in fig. 2, in the present application, an amplifier 170 may also be provided. The amplifier 170 is used to further increase the power of the kerr comb 137 by doing so before the beam 135 is injected into the microcavity 110.

Fig. 5 is a schematic block diagram showing still another example of the multiwavelength light source generator 100 of the present application. As shown in fig. 5, the multi-wavelength light source generator 100 further includes a controller 180, and the controller 180 is configured to control the concentration of the rare earth element ions in the micro-cavity 110.

By way of example and not limitation, the controller 180 controls the power of the kerr comb 137 output from the output port of the microcavity 110. For example, as shown in fig. 5, the multi-wavelength light source generator 100 further includes a detector 185. The detector 185 is used to detect the power of the kerr optical comb 137 (hereinafter, for convenience of understanding and explanation, referred to as power a) output from the microcavity 110. And, the detector 185 generates information indicating the power a. The detector 185 is communicatively coupled to the controller 180 such that the controller 180 receives the information from the detector 185 to obtain the power a. Thereafter, the controller 180 adjusts the operating parameters of the ion generator 120 based on the power a such that the power a satisfies the preset condition.

By way of example and not limitation, the preset condition may be that the manufacturer is configured in the controller 180 at the time of shipping the multiwavelength light source generator 100. Alternatively, the preset condition may be preset by the user.

In addition, the above-mentioned working parameters may adopt one or more of the following parameters: the time of irradiation of the beam 145 on the substance 121, the spot size of the beam 145 (e.g., the size of the spot of the beam 145 on the substance 121), or the power of the beam 145. It should be understood that the above listed operating parameters are exemplary only and that other parameters capable of affecting the power of the kerr optical comb 137 are within the scope of the present application. The operating parameters may also include, for example, the size of the substance, e.g., the length of the erbium doped fiber.

According to the scheme provided by the application, the rare earth element ions are doped in the microcavity, so that the gain g can exist in the microcavity. That is, in the present application, a0+ κ + g is smaller than a0+ κ in the related art, and g is smaller than a. Thus, as long as the gain g is sufficient to compensate for κ, κ may be increased without affecting the microcavity Q, thereby increasing the output power of the output kerr comb.

For example, for a passive microcavity with a Q of 108, κ is about 0.007 under critical coupling conditions; if the active microcavity is adopted, the coupling coefficient is improved by 10 times, and meanwhile, only 0.07 gain coefficient is needed to be provided, namely, the gain system g is provided with 0.0025 each time (namely, g is ln [ (1-0.07)²)^-0.5)]) Under the condition of ensuring that the total loss a (namely the Q value) is not changed, the Kerr optical comb power of the output microcavity can be improved by 20 dB. Meanwhile, because the optical field enhancement factor B in the microcavity is proportional to kappa²And kappa is increased by 10 times, so that the highest pumping power in the cavity can be increased by 20dB theoretically, and the Kerr optical comb power of the output microcavity can be further increased.

As shown in fig. 6, (a) in fig. 6 is a simulated spectral line of a kerr optical comb (or soliton mode-locked kerr optical comb) generated based on a conventional microcavity and (b) in fig. 8 is a kerr optical comb generated based on a microcavity of the present application under the condition that the Q values of the microcavities are the same, the parameters of the conventional microcavity are as follows: k is 0.007, alpha 0 is-2.5 e^-5And g is 0. The input pump light power set during simulation is at 13dBm, and the soliton mode-locked kerr light frequency comb line generated by the passive microcavity is shown in (a) of fig. 6. The technical scheme is used for carrying out analog simulation analysisThe power of the laser 140 is first adjusted to control the working gain in the erbium-doped microcavity to g-0.0025, and the loss value alpha 0 of the conventional passive microcavity to-2.5 e^-5On the premise of ensuring that the Q value of the microcavity is unchanged, when κ is 0.07, the coupling coefficient is one order of magnitude higher than that of the passive microcavity, and when the input pump light power is also 13dBm, the soliton mode-locked kerr optical comb spectral line obtained by simulation is as shown in (b) of fig. 6. Comparing the two graphs, the technical scheme of the invention can improve the Kerr optical comb power output by about 20dB compared with the traditional passive microcavity technical scheme under the condition of the same input optical power, and the power flatness of the optical comb has no change.

Fig. 7 is a schematic flow chart of an example of a method 200 of generating a multi-wavelength light source of the present application. As shown in fig. 7, the method 200 includes the steps of:

at S210, a microcavity (e.g., a whispering gallery microcavity) is doped with rare earth ions.

This process may be implemented by controlling the ion generator 120 described above. Alternatively, this process may be implemented automatically by the ion generator 120 described above. For example, a rare-earth-doped fiber (e.g., an erbium-doped fiber) is arranged in the microcavity, and a beam B is irradiated to the rare-earth-doped fiber, thereby releasing rare-earth ions from the rare-earth-doped fiber into the microcavity.

Optionally, at S212, beam B is filtered before being impinged into the microcavity.

This process may be implemented by controlling the above-described filter 160, or the process may be implemented by automatically executing the above-described filter 160.

At S220, a single-wavelength light beam a is irradiated to the microcavity;

the beam a is capable of generating a multi-wavelength light source by the kerr effect within the microcavity. And the multi-wavelength light source is output after being amplified by power under the amplification action of the rare earth element ions.

Optionally, at S222, the beam a is filtered before being irradiated into the microcavity.

This process may be implemented by controlling the filter 150 described above. Alternatively, this process may be implemented automatically by the filter 150 described above.

Optionally, at S224, the beam a is amplified before being irradiated into the microcavity.

This process may be implemented by controlling the amplifier 170 described above. Alternatively, this process may be implemented automatically by the amplifier 170 described above. By way of example and not limitation, this amplification process may be achieved by irradiating pump light to the rare-earth element ions, and the above-described beam B may be used as the pump light.

Optionally, at S230, the microcavity is heated;

doing so can supplement the thermal effects in the microcavity in order to produce a stable multi-wavelength light source (e.g., a soliton mode-locked Kerr comb) in the microcavity. By way of example and not limitation, a secondary beam may be directed at the microcavity to heat the microcavity. Also, the above-described beam B may be used as an auxiliary beam.

Optionally, at S240, the concentration of rare earth element ions within the microcavity is controlled.

For example, the power of a multi-wavelength light source output from the microcavity is detected. And adjusting the concentration of the rare earth element ions in the microcavity based on the power of the multi-wavelength light source until the power of the multi-wavelength light source meets a preset condition or requirement. And the adjustment process of the concentration of the rare earth element ions in the micro-cavity is realized by adjusting the working parameters.

Wherein the process may be implemented by controlling the controller 180 described above. Alternatively, the process can be implemented by the controller 180 and detector 185 described above in conjunction.

The steps performed by the controller 180 in the method 200, for example, the step S240, may be automatically performed by the controller 180, that is, when the controller 180 can read the software program in the storage unit, interpret and execute the instructions of the software program, process the data of the software program, and further control each device of the multi-wavelength light source generator 100 to perform its own function, so as to perform the method 200.

For example, the controller 180 may be implemented by a processor, and the processor may include a central processing unit that is mainly used to control the entire terminal device, execute a software program, and process data of the software program.

It should be understood that, in the embodiments of the present application, the processor may be a Central Processing Unit (CPU), other general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

It will also be appreciated that the memory in the embodiments of the subject application may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of Random Access Memory (RAM) are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct bus RAM (DR RAM).

The actions or methods performed by the controller 180 may be implemented in whole or in part by software, hardware, firmware, or any other combination. When implemented in software, the actions or methods performed by the controller 180 may be implemented in whole or in part in the form of a computer program product. The computer program product comprises one or more computer instructions or computer programs. The procedures or functions described in accordance with the embodiments of the present application are produced in whole or in part when the computer instructions or the computer program are loaded or executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, data center, etc., that contains one or more collections of available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium may be a solid state disk.

Fig. 8 is a schematic structural diagram of a possible light emitting device according to an embodiment of the present disclosure. Specifically, the optical transmission device 300 includes a multi-wavelength light source generator 100, a wavelength division demultiplexer 301, modulators (302a to 302c), and a wavelength division multiplexer 303. The light emitting device 100 is a multi-wavelength light emitting device. The multi-wavelength light source provides a plurality of wavelengths, and the plurality of wavelengths are separated by the wavelength division demultiplexer 301 and then input to the corresponding modulators, respectively. The modulator may load the data to be transmitted onto the corresponding wavelength. Finally, the multiple data-loaded wavelengths are combined by the wavelength division multiplexer 303 and transmitted through an optical fiber. Note that the wavelength to which data is loaded is also referred to as an optical signal.

It should be noted that the multi-wavelength light source generator 100 may be replaced by any one of the structures of the multi-wavelength light source generator in fig. 1, fig. 2, or fig. 5, or may be an alternative specific implementation manner provided in the foregoing description. The number of the modulators is not more than the number of wavelengths provided by the optical frequency comb light source.

Specifically, the light emitting device 300 may be the aforementioned transmission-side apparatus and/or reception-side apparatus. Alternatively, the light emitting device 300 may also be a light module, such as: an optical transmitter or an optical transceiver.

It should be understood that, in the various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application. It can be clearly understood by those skilled in the art that, for convenience and simplicity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again. In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment. In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: u disk, removable hard disk, read only memory, random access memory, magnetic or optical disk, etc. for storing program codes.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A multi-wavelength light source generator, comprising: a first laser, a microcavity, and an ion generator, wherein,

the ion generator is used for doping rare earth element ions into the microcavity;

the first laser is used for outputting a first light beam to the microcavity, and the first light beam is a single-wavelength light beam;

the microcavity is used for enabling the first light beam to generate a Kerr effect to generate a multi-wavelength light source, and amplifying the multi-wavelength light source by utilizing the rare earth element ions and then outputting the multi-wavelength light source;

wherein the ion generator comprises: a first medium and a second laser, the composition substance of the first medium including the rare earth element ions, and the first medium being disposed within the micro-cavity;

the second laser is used for irradiating a second light beam to the first medium.

2. The multiwavelength light source generator of claim 1, wherein the rare earth element ions comprise erbium ions.

3. The multiwavelength light source generator of claim 1 or 2, wherein the ion generator further comprises:

a first filter for filtering the second beam before it impinges on the first medium.

4. The multiwavelength light source generator of claim 1 or 2, wherein the first medium comprises erbium doped optical fibre.

5. The multiwavelength light source generator of claim 1 or 2, wherein the microcavity comprises a waveguide and a cavity, wherein,

the first light beam is input to the waveguide from the first light-transmitting port of the waveguide and coupled to the cavity from the waveguide,

the second light beam is input to the waveguide from the second light-passing port of the waveguide and is coupled from the waveguide to the cavity.

6. The multiwavelength light source generator of claim 5, wherein the first light admission port is disposed opposite the second light admission port.

7. The multiwavelength light source generator of claim 1 or 2, further comprising:

a controller for controlling the concentration of the rare earth element ions in the micro-cavity.

8. The multiwavelength light source generator of claim 7, further comprising:

a detector for detecting the power of the multi-wavelength light source output from the microcavity; and

the controller is specifically configured to control the concentration of the rare earth element ions in the microcavity according to the power of the multi-wavelength light source, so that the power of the multi-wavelength light source satisfies a preset condition.

9. The multiwavelength light source generator of claim 7, wherein the controller is particularly adapted to adjust at least one of the following parameters to control the concentration of the rare earth element ions within the microcavity:

a time of irradiating the substance which releases the rare earth element ion, a spot size of a beam which irradiates the substance which releases the rare earth element ion, or a power of a beam which irradiates the substance which releases the rare earth element ion.

10. The multiwavelength light source generator of claim 1 or 2, further comprising:

a second filter for filtering the first light beam before the first light beam enters the microcavity.

11. The multiwavelength light source generator of claim 1 or 2, further comprising:

and the power amplifier is used for amplifying the power of the first light beam before the first light beam is emitted into the microcavity.

12. A method of generating a multiwavelength light source, comprising:

doping rare earth element ions into the microcavity by using an ion generator;

irradiating a first light beam to the microcavity, wherein the first light beam is a single-wavelength light beam, so that the first light beam generates a Kerr effect to generate a multi-wavelength light source;

amplifying the multi-wavelength light source using the rare earth element ions;

outputting the amplified multi-wavelength light source;

wherein the doping of the rare earth element ions into the microcavity by the ion generator comprises:

irradiating a second light beam to a first medium disposed in the micro-cavity using the ion generator, wherein a constituent substance of the first medium includes the rare earth element ions.

13. The method of claim 12, wherein the rare earth element ions comprise erbium ions.

14. The method according to claim 12 or 13, characterized in that the method further comprises:

filtering the second beam of light before it impinges on the first medium.

15. A method according to claim 12 or 13, wherein the first medium comprises erbium doped fibre.

16. The method of claim 12 or 13, wherein the microcavity comprises a waveguide and a cavity, and

17. The method of claim 16, wherein the first light admission port is disposed opposite the second light admission port.

18. The method according to claim 12 or 13, further comprising:

adjusting a concentration of ions of the rare earth element within the microcavity.

19. The method of claim 18, further comprising:

detecting power of a multi-wavelength light source output from the microcavity; and

the adjusting the concentration of the rare earth element ions within the micro-cavity comprises:

and adjusting the concentration of the ions of the rare earth elements in the microcavity according to the detection of the power of the multi-wavelength light source output from the microcavity, so that the power of the multi-wavelength light source output from the microcavity meets a preset condition.

20. The method of claim 18, wherein said adjusting the concentration of the rare earth element ions within the microcavity comprises:

adjusting at least one of the following parameters to control the concentration of the rare earth element ions within the microcavity:

21. The method according to claim 12 or 13, characterized in that the method further comprises:

filtering the first beam before the first beam is input into the microcavity.

22. The method according to claim 12 or 13, further comprising:

power amplifying the first beam of light before the first beam of light is input into the microcavity.

23. An optical transmission apparatus comprising the multiwavelength light source generator, the wavelength division demultiplexer, the modulator, and the wavelength division multiplexer according to any one of claims 1 to 11,

the wavelength division demultiplexer is used for separating the multi-wavelength light beams generated by the multi-wavelength light source generator and then respectively inputting the multi-wavelength light beams into the corresponding modulators;

the modulator is used for loading the data to be transmitted to the corresponding wavelength;

the wavelength division multiplexer combines a plurality of wavelengths loaded with data and transmits the wavelengths through optical fibers.