CN212062995U - Optical soliton generating system - Google Patents
Optical soliton generating system Download PDFInfo
- Publication number
- CN212062995U CN212062995U CN202021103466.1U CN202021103466U CN212062995U CN 212062995 U CN212062995 U CN 212062995U CN 202021103466 U CN202021103466 U CN 202021103466U CN 212062995 U CN212062995 U CN 212062995U
- Authority
- CN
- China
- Prior art keywords
- optical
- soliton
- circulator
- pump light
- light
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 194
- 230000010287 polarization Effects 0.000 claims abstract description 54
- 239000013307 optical fiber Substances 0.000 claims abstract description 52
- 238000005086 pumping Methods 0.000 claims abstract description 24
- 239000000758 substrate Substances 0.000 claims abstract description 17
- 230000008878 coupling Effects 0.000 claims abstract description 12
- 238000010168 coupling process Methods 0.000 claims abstract description 12
- 238000005859 coupling reaction Methods 0.000 claims abstract description 12
- 230000000694 effects Effects 0.000 claims abstract description 9
- 238000002156 mixing Methods 0.000 claims abstract description 8
- 238000001914 filtration Methods 0.000 claims abstract description 3
- 239000004065 semiconductor Substances 0.000 claims description 15
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 14
- 238000001228 spectrum Methods 0.000 claims description 14
- 239000000835 fiber Substances 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 8
- 229910052710 silicon Inorganic materials 0.000 claims description 5
- 239000010703 silicon Substances 0.000 claims description 5
- 235000012239 silicon dioxide Nutrition 0.000 claims description 4
- 239000000377 silicon dioxide Substances 0.000 claims description 4
- 238000000034 method Methods 0.000 abstract description 15
- 230000010354 integration Effects 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract 2
- 230000033228 biological regulation Effects 0.000 abstract 1
- 230000002349 favourable effect Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 22
- 238000000411 transmission spectrum Methods 0.000 description 9
- 230000008859 change Effects 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 6
- 229910052814 silicon oxide Inorganic materials 0.000 description 6
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 4
- 239000006185 dispersion Substances 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000002547 anomalous effect Effects 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000002269 spontaneous effect Effects 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 210000001520 comb Anatomy 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- ORUIBWPALBXDOA-UHFFFAOYSA-L magnesium fluoride Chemical compound [F-].[F-].[Mg+2] ORUIBWPALBXDOA-UHFFFAOYSA-L 0.000 description 1
- 229910001635 magnesium fluoride Inorganic materials 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000009022 nonlinear effect Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000008707 rearrangement Effects 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
Landscapes
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
- Lasers (AREA)
Abstract
The embodiment of the utility model discloses light soliton produces system. The system comprises a wavelength-adjustable light source, a polarization controller, a first circulator, an optical fiber, a first filter and an optical microcavity; the optical microcavity comprises a substrate, a supporting column and a cavity, wherein the supporting column and the cavity are positioned on one side of the substrate; the wavelength tunable light source is used for providing pump light; the polarization controller is used for adjusting the polarization direction of the pump light so as to adjust the coupling efficiency of the pump light and the optical microcavity; the pump light excites backward Brillouin laser in the optical microcavity, the backward Brillouin laser generates a four-wave mixing effect in the optical microcavity, and dissipative Kerr solitons are generated; the first filter is used for filtering the pumping light and the backward Brillouin laser to output dissipative Kerr solitons. The technical scheme of the utility model, utilize the brillouin laser production dissipation kerr soliton dorsad, can avoid forming the thermal instability of in-process pump light red detuning at the soliton and arouse complicated regulation technique, be favorable to realizing the miniaturization and the integration of light soliton production system.
Description
Technical Field
The embodiment of the utility model provides a relate to laser technology, especially relate to a light soliton produces system.
Background
An optical soliton is a pulse that can keep the time domain waveform and the spectrum shape unchanged during transmission. The dissipative time domain Kerr solitons based on the microcavity utilize parametric gain to compensate the loss of the microcavity and the balance of dispersion and Kerr nonlinearity, so that pulses with the pulse width of femtosecond level and the repetition frequency in the range from GHz to THz can be generated, and the pulses are represented as phase-locked optical frequency combs with equal intervals on the frequency domain. The micro-cavity soliton frequency comb has a wide spectrum and high repetition frequency, can be integrated on a chip, and has wide application in the aspects of coherent light communication, low-noise microwave sources, double-light comb spectrum, optical ranging, optical frequency synthesis, optical clocks and the like.
In order to realize the micro-cavity soliton frequency comb, the pumping laser needs to be modulated to the red detuning of a pumping cavity mode, and when the soliton is formed, the transmission spectrum of the optical comb power appears in a step shape along with the scanning of the pumping laser frequency, so that the frequency range of the pumping laser when the soliton exists is displayed. Since the thermo-optic nonlinearity of the optical microcavity can cause the cavity mode frequency red shift, the pump laser is thermally unstable in the red detuning mechanism, and the soliton state needs to be realized by using pump power modulation (power chopping), rapid adjustment of the laser frequency, or compensation of the thermal effect. The methods are complex in technology, the frequency range of the pump laser in the soliton existing region is small, extra electrical and optical components need to be introduced to adjust the power or frequency of the laser in the cavity, and the development of system miniaturization and integration is not facilitated.
SUMMERY OF THE UTILITY MODEL
The embodiment of the utility model provides an optical soliton produces system, this system utilize the continuous pumping laser of single mode of blue detuning earlier to produce the back brillouin laser of red detuning in the optics microcavity, then utilize the back brillouin laser to produce dissipation kerr soliton. Because the pump laser is in a thermal stable state of blue detuning, the soliton state can be realized by directly manually adjusting the piezoelectric of the laser, the complex adjusting technology caused by the thermal instability of the red detuning of the pump laser in the soliton forming process is avoided, and the miniaturization and the integration of the optical soliton generating system are favorably realized.
The embodiment of the utility model provides an optical soliton generation system, including wavelength tunable light source, polarization controller, first circulator, optic fibre, first wave filter and optics microcavity;
the output end of the wavelength-tunable light source is connected with the input end of the polarization controller, the output end of the polarization controller is connected with the first end of the first circulator, the second end of the first circulator is connected with the optical fiber, and the third end of the first circulator is connected with the input end of the first filter;
the optical fiber extends from the second end of the first circulator to the optical microcavity, the optical fiber extending to the optical microcavity comprises a tapered structure, and the optical fiber is coupled with the optical microcavity through the tapered structure;
the optical microcavity comprises a substrate, a supporting column and a cavity, wherein the supporting column and the cavity are positioned on one side of the substrate;
the wavelength-adjustable light source is used for providing pump light, and the pump light is coupled into the optical fiber after passing through the polarization controller and the first circulator;
the polarization controller is used for adjusting the polarization direction of the pump light so as to adjust the coupling efficiency of the pump light and the optical microcavity;
the pump light is coupled into the optical microcavity through the conical structure, the pump light excites backward Brillouin laser in the optical microcavity, and the backward Brillouin laser generates a four-wave mixing effect in the optical microcavity to generate a dissipative Kerr soliton;
the dissipative Kerr soliton is coupled into the optical fiber, is input from the second end of the first circulator and is output from the third end of the first circulator;
the first filter is used for filtering the pumping light and the backward Brillouin laser to output the dissipative Kerr soliton.
Optionally, the optical amplifier is disposed between the wavelength tunable light source and the polarization controller, and the optical amplifier is configured to amplify the pump light.
Optionally, the optical amplifier is a semiconductor optical amplifier;
the optical soliton generation system further comprises a first collimator, an optical isolator and a second collimator;
the first collimator, the semiconductor optical amplifier, the optical isolator and the second collimator are sequentially arranged between the wavelength-tunable light source and the polarization controller along a light path;
the input end of the first collimator is coupled with the output end of the wavelength-adjustable light source and is used for collimating the pump light and then inputting the collimated pump light into the semiconductor optical amplifier;
the semiconductor optical amplifier is used for amplifying the pump light;
the optical isolator is used for enabling the amplified pump light to be transmitted in a single direction;
and the output end of the second collimator is connected with the input end of the polarization controller.
Optionally, the optical amplifier is an optical fiber amplifier;
the wavelength-adjustable light source is connected with the input end of the optical fiber amplifier;
and the output end of the optical fiber amplifier is connected with the polarization controller.
Optionally, the polarization controller further comprises a second filter disposed between the optical amplifier and the polarization controller, and the second filter is configured to filter the spontaneous emission light of the optical amplifier.
Optionally, the optical amplifier further comprises an adjustable attenuator arranged between the optical amplifier and the polarization controller, and the adjustable attenuator is used for adjusting the output power of the amplified pump light.
Optionally, the system further comprises a coupler, a first photodetector, a second photodetector, an oscilloscope and a spectrometer;
the optical fiber extending from the optical microcavity is connected with the first photodetector, the output end of the first filter is connected with the second photodetector, the first photodetector and the second photodetector are both connected with the oscilloscope, and the oscilloscope is used for outputting time domain waveforms detected by the first photodetector and the second photodetector;
the input end of the coupler is connected with the second end of the first circulator, the first output end of the coupler is connected with the input end of the first filter, the second output end of the coupler is connected with the spectrometer, and the spectrometer is used for measuring the output spectrum of the second output end of the coupler.
Optionally, the first filter includes a fiber bragg grating, and the fiber bragg grating is configured to reflect the pump light and the backward brillouin laser light and transmit the dissipative kerr soliton;
the optical soliton generation system further comprises a second circulator, wherein a first end of the second circulator is connected with a first output end of the coupler, a second end of the second circulator is connected with an input end of the first filter, and a third end of the second circulator is connected with the spectrometer;
the spectrometer is further configured to measure an output spectrum of a third end of the second circulator.
Optionally, the wavelength-tunable light source is a wavelength-tunable laser.
Optionally, the substrate material of the optical microcavity includes silicon, and the material of the cavity includes silicon dioxide.
The embodiment of the utility model provides an optical soliton generation system, including wavelength tunable light source, polarization controller, first circulator, optic fibre, first wave filter and optics microcavity; the optical microcavity comprises a substrate, a supporting column and a cavity, wherein the supporting column and the cavity are positioned on one side of the substrate; the pump light is provided by the wavelength-adjustable light source and is positioned in the blue detuning region of the optical microcavity, so that the optical microcavity has good thermal stability; the pump light is coupled into the optical fiber after passing through the polarization controller and the first circulator; the polarization direction of the pump light is adjusted through the polarization controller to adjust the coupling efficiency of the pump light and the optical microcavity, the pump light excites backward Brillouin laser in the optical microcavity, the mode of the backward Brillouin laser is just in an anomalous dispersion region of the optical microcavity, the backward Brillouin laser generates a four-wave mixing effect in the optical microcavity, and a dissipative Kerr soliton is generated; the dissipative Kerr soliton is coupled into the optical fiber, is input from the second end of the first circulator and is output from the third end of the first circulator; the first filter filters the pumping light and the backward Brillouin laser, and the output of the dissipative Kerr soliton is achieved. The optical soliton generation system provided by the embodiment can avoid a complex adjusting technology caused by thermal instability of pump laser red detuning in the soliton forming process, and is beneficial to realizing miniaturization and integration of the optical soliton generation system.
Drawings
Fig. 1 is a schematic structural diagram of an optical soliton generation system according to an embodiment of the present invention;
fig. 2 is a schematic diagram illustrating the principle of optical soliton generation provided by the embodiment of the present invention;
fig. 3 is a schematic structural diagram of an optical microcavity provided by an embodiment of the present invention;
fig. 4 is a schematic structural diagram of another optical soliton generation system provided by an embodiment of the present invention;
fig. 5 is a schematic structural diagram of another optical soliton generation system provided by an embodiment of the present invention;
fig. 6 is a schematic structural diagram of another optical soliton generation system provided by an embodiment of the present invention;
fig. 7 is a schematic structural diagram of another optical soliton generation system provided by an embodiment of the present invention;
fig. 8 is a schematic structural diagram of another optical soliton generation system provided by an embodiment of the present invention;
fig. 9 is a schematic diagram of waveforms collected by an oscilloscope according to an embodiment of the present invention;
fig. 10 is a schematic spectrum diagram of an optical soliton collected by a spectrometer in an embodiment of the present invention;
fig. 11 is a schematic spectrum diagram of the pump light collected by the spectrometer and the backward brillouin laser in the embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. It should be noted that the terms "upper", "lower", "left", "right", and the like used in the embodiments of the present invention are described in terms of the drawings, and should not be construed as limiting the embodiments of the present invention. In addition, in this context, it is also to be understood that when an element is referred to as being "on" or "under" another element, it can be directly formed on "or" under "the other element or be indirectly formed on" or "under" the other element through an intermediate element. The terms "first," "second," and the like, are used for descriptive purposes only and not for purposes of limitation, and do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
Currently, soliton frequency combing has been implemented in optical microcavities of materials such as magnesium fluoride, silicon oxide, silicon nitride, and the like. The silicon oxide micro-cavity integrated on the chip has an ultrahigh quality factor, and can realize a soliton frequency comb with detectable repetition frequency. Since the silicon oxide material has a large thermo-optic nonlinear coefficient, it has been realized to utilize power modulation (power chopping), single sideband modulation, and a method of compensating the thermal effect using auxiliary light to tune the pump laser to red detune to generate optical solitons. In the power modulation method, the acousto-optic modulator is required to be used for quickly reducing the power of the pumping light, so that the intracavity heat effect and the Kerr nonlinear effect are weakened, the cavity mode is blue-shifted, the detuning of the pumping light relative to the cavity mode reaches a red detuning area, the pumping power is quickly improved, and the detuning range of solitons is expanded (the higher the pumping power is, the larger the detuning range of the solitons is); in the single-sideband modulation method, a single-sideband modulator is required to adjust the frequency scanning speed of the pump laser to enable the pump laser to reach a red detuning state, and a PDH (Pound-Drever-Hall) locking technology is used for stabilizing the detuning of the pump laser; the thermal compensation method needs to utilize additional auxiliary laser to be coupled into the cavity, and compensates cavity mode frequency change caused by laser power change in the cavity when the pump laser is adjusted from blue detuning to red detuning, so that the optical soliton state can be stably realized by adjusting the laser frequency. The methods all need to introduce additional electrical and optical components, the frequency range of the pump laser in which solitons exist is relatively narrow, and the frequency adjustment method of the pump laser is complex, so that the miniaturization and integration development of optical devices are not facilitated.
In order to solve the above problem, fig. 1 is a schematic structural diagram of an optical soliton generation system according to an embodiment of the present invention. Referring to fig. 1, the optical soliton generation system provided in this embodiment includes a wavelength tunable light source 10, a polarization controller 20, a first circulator 30, an optical fiber 40, a first filter 50, and an optical microcavity 60; the output end of the wavelength tunable light source 10 is connected to the input end of the polarization controller 20, the output end of the polarization controller 20 is connected to the first end of the first circulator 30, the second end of the first circulator 30 is connected to the optical fiber 40, and the third end of the first circulator 30 is connected to the input end of the first filter 50; the optical fiber 40 extends from the second end of the first circulator 30 to the optical microcavity 60, the optical fiber 40 extending to the optical microcavity 60 including a tapered structure (not shown in fig. 1), the optical fiber 40 being coupled with the optical microcavity 60 through the tapered structure; wherein, the optical microcavity 60 includes a substrate and a supporting pillar and a cavity on one side of the substrate; the wavelength tunable light source 10 is used for providing pump light, and the pump light is coupled into the optical fiber 40 after passing through the polarization controller 20 and the first circulator 30; the polarization controller 20 is configured to adjust the polarization direction of the pump light to adjust the coupling efficiency of the pump light and the optical microcavity 60; the pump light is coupled into the optical microcavity 60 through the conical structure, the pump light excites backward Brillouin laser in the optical microcavity 60, the backward Brillouin laser generates a four-wave mixing effect in the optical microcavity 60, and dissipative Kerr solitons are generated; the dissipative kerr solitons are coupled into the optical fiber 40, input from the second end of the first circulator 30 and output from the third end of the first circulator 30; the first filter 60 is used to filter out the pump light and the backward brillouin laser light to output a dissipative kerr soliton.
The wavelength tunable light source 10 is capable of outputting a continuously tunable pump light within a predetermined wavelength range, for example, a pump light in 1550nm band. The wavelength tunable light source 10, the polarization controller 20, the first circulator 30, and the first filter 50 may be connected by optical fibers. The embodiment of the utility model provides an utilize brillouin scattering principle, produce brillouin laser at first in optics microcavity 60, then utilize brillouin laser to produce dissipation kerr soliton. Wherein the pumping mode and the Brillouin mode belong to different mode families, and the Brillouin mode family is in an anomalous dispersion region. By properly selecting the pumping mode with proper mode spacing and the Brillouin mode and adjusting the power of the pumping light, Brillouin laser in a red detuning region can be obtained, and the pumping light is in a blue detuning region. The width of the soliton step generated by the method can reach tens of megahertz, and the soliton step can be directly adjusted to a soliton state by adjusting the frequency of the laser. The embodiment of the utility model provides a pump tuned frequency region that has solved the soliton under the prior art is narrower, needs the supplementary not enough that produces of extra electric modulator. The optical microcavity 60 is an on-chip integrated device, which can be integrated on a silicon chip as a substrate, and it can be understood that light transmitted in the optical fiber 40 generates an evanescent field in a tapered structure, so as to realize coupling between the optical microcavity 60 and the optical fiber 40, and the tapered structure can be obtained by melting and tapering the optical fiber. Through adjusting the state of polarization controller 20, can adjust the coupling efficiency of pump light and optics microcavity 60, wherein polarization controller 20 can adopt tricyclic formula or embedded polarization controller, the embodiment of the utility model provides a do not restrict to this.
For example, fig. 2 is a schematic diagram illustrating the principle of optical soliton generation according to an embodiment of the present invention. Referring to fig. 2(a), the pump light p is coupled into the optical microcavity 60 through the optical fiber 40 to generate the back brillouin laser b, and when the power of the backward-transmitted back brillouin laser b exceeds the four-wave mixing threshold, the back brillouin laser b can be used as the pump light to generate the dissipative kerr soliton. The backward Brillouin laser b and the Kerr frequency comb generated by the backward Brillouin laser b are coupled out from the backward direction and enter the second end of the first circulator.
Referring to FIG. 2(b), ω1、ω2、ω3And ω4Respectively representing the frequency of the pumping cavity mode, the frequency of the Brillouin cavity mode, the Brillouin cavity mode frequency shift caused by the Kerr self-phase modulation of the Brillouin laser, and the central frequency of the Brillouin gain, omegapIn the blue detuning region, omega, for pumping the laser frequencysAt the brillouin laser frequency, in the red detuned region, Ω denotes the frequency of the acoustic mode. The detuning of the Brillouin laser can be obtained by a coupling mode equation
Wherein gamma ismLine width, γ, representing an acoustic mode2The line width, g, of the Brillouin cavity mode2Denotes the Kerr nonlinear coefficient, asIndicating the brillouin laser amplitude and omega the acoustic mode frequency. The first term represents the detuning change of the brillouin laser caused by kerr self-phase modulation of the brillouin laser, wherein the kerr self-phase modulation can cause red shift of a brillouin cavity mode and equivalently can cause red shift of the frequency of the brillouin laser, so that the generated brillouin laser is in red detuning; the second term represents the detuning change of the brillouin laser caused by the mismatch of the brillouin cavity mode frequency, the pumping laser frequency and the acoustic mode, and when the frequency difference of the pumping laser and the brillouin cavity mode is smaller than the acoustic mode frequency, the generated brillouin laser is also in red detuning. Due to gamma in the microcavitym＞＞γsThe change in the pump laser frequency is much greater than the resulting change in the brillouin detuning. In the experiment, when the pump laser frequency is adjusted to change the detuning of the brillouin laser, a larger pump laser frequency range is provided corresponding to the brillouin laser detuning range with solitonsI.e. the soliton step is longer when the pump laser frequency is swept.
According to the technical scheme of the embodiment, the pump light is provided by the wavelength-adjustable light source and is positioned in the blue detuning region of the optical microcavity, so that the optical microcavity has good thermal stability; the pump light is coupled into the optical fiber after passing through the polarization controller and the first circulator; the polarization direction of the pump light is adjusted through the polarization controller to adjust the coupling efficiency of the pump light and the optical microcavity, the pump light excites backward Brillouin laser in the optical microcavity, the mode of the backward Brillouin laser is just in an anomalous dispersion region of the optical microcavity, the backward Brillouin laser generates a four-wave mixing effect in the optical microcavity, and a dissipative Kerr soliton is generated; the dissipative Kerr soliton is coupled into the optical fiber, is input from the second end of the first circulator and is output from the third end of the first circulator; the first filter filters the pumping light and the backward Brillouin laser, and the output of the dissipative Kerr soliton is achieved. The optical soliton generation system provided by the embodiment can avoid a complex adjusting technology caused by thermal instability of pump laser red detuning in the soliton forming process, and is beneficial to realizing miniaturization and integration of the optical soliton generation system.
On the basis of the above technical solution, optionally, the wavelength-tunable light source is a wavelength-tunable laser.
It can be understood that, because the laser has many advantages such as high brightness, good directivity, good monochromaticity, etc., in practical implementation, the wavelength tunable light source may be a wavelength tunable laser and output through an optical fiber to generate high-power pump light.
Optionally, the substrate material of the optical microcavity comprises silicon, and the material of the cavity comprises silicon dioxide.
Fig. 3 is a schematic structural diagram of an optical microcavity according to an embodiment of the present invention. Referring to fig. 3, the optical microcavity is a microcavity including a substrate 61 and a support post 62 and a microdisk 63 located on one side of the substrate. Both the substrate 61 and the support posts 62 may be selected from silicon and the microdisk cavities 63 may be selected from silicon dioxide. In this embodiment, the microdisk cavity 63 is a circular truncated cone, and the circular truncated cone is coupled to the optical fiber through a tapered structure of the optical fiber.
Fig. 4 is a schematic structural diagram of another optical soliton generation system according to an embodiment of the present invention. Referring to fig. 4, optionally, the optical soliton generation system provided in this embodiment further includes an optical amplifier 11 disposed between the wavelength tunable light source 10 and the polarization controller 20, where the optical amplifier 11 is configured to amplify the pump light.
It is understood that, in implementation, the power of the pump light output by the wavelength tunable light source 10 may be small and may not reach the threshold power of the pump light that excites the backward brillouin laser in which four-wave mixing may occur, and therefore, the optical amplifier 11 may be disposed on the optical path between the wavelength tunable light source 10 and the polarization controller 20 to amplify the power of the pump light above the threshold power.
Fig. 5 is a schematic structural diagram of another optical soliton generation system according to an embodiment of the present invention. Referring to fig. 5, the optical amplifier 11 is optionally a semiconductor optical amplifier; the optical soliton generation system further includes a first collimator 12, an optical isolator 13, and a second collimator 14; the first collimator 12, the semiconductor optical amplifier, the optical isolator 13 and the second collimator 14 are sequentially arranged along a light path between the wavelength-tunable light source 10 and the polarization controller 20; the input end of the first collimator 12 is coupled with the output end of the wavelength-tunable light source 10, and is used for collimating the pump light and inputting the collimated pump light into the semiconductor optical amplifier; the semiconductor optical amplifier is used for amplifying the pump light; the optical isolator 13 is used for unidirectional transmission of the amplified pump light; an output of the second collimator 14 is connected to an input of a polarization controller 20.
It can be understood that the semiconductor optical amplifier is difficult to integrate with the optical fiber, the wavelength-tunable light source 10 can output pump light through the optical fiber, after passing through the first collimator 12, the transmission light in the optical fiber is converted into parallel light in a free space, and the pump light is gain-amplified after the optical power is improved through the semiconductor optical amplifier, after passing through the optical isolator 13, the amplified pump light can only be transmitted along the forward direction, the back reflected light is prevented from damaging the semiconductor optical amplifier, and after passing through the second collimator 14, the free space parallel light after the power amplification is recoupled and enters the optical fiber for continuous transmission.
Optionally, the optical amplifier is an optical fiber amplifier; the wavelength-adjustable light source is connected with the input end of the optical fiber amplifier; the output end of the optical fiber amplifier is connected with the polarization controller.
It can be understood that the optical amplifier may also be an optical fiber amplifier, and the optical path is transmitted only in the optical fiber, so as to reduce the coupling difficulty of the optical path. In other embodiments, other types of optical amplifiers may be used, which is not limited in the embodiments of the present invention.
Optionally, with continuing reference to fig. 4, the optical soliton generation system further includes a second filter 70 disposed between the optical amplifier 11 and the polarization controller 20, where the second filter 70 is configured to filter the spontaneous emission light of the optical amplifier 11 to reduce the noise of the pump light.
Optionally, with continued reference to fig. 4, the optical soliton generation system further includes an adjustable attenuator 80 disposed between the optical amplifier 11 and the polarization controller 20, wherein the adjustable attenuator 80 is used for adjusting the output power of the amplified pump light.
It is understood that the second filter 70 shown in fig. 4 is located at the output end of the adjustable attenuator 80 for illustration purposes only, and the implementation thereof is not limited to the sequential relationship.
Fig. 6 is a schematic structural diagram of another optical soliton generation system according to an embodiment of the present invention. Referring to fig. 6, optionally, the optical soliton generation system provided in this embodiment further includes a coupler 90, a first photodetector 91, a second photodetector 92, an oscilloscope 93, and a spectrometer 94; the optical fiber 40 extending from the optical microcavity 60 is connected to a first photodetector 91, the output end of the first filter 50 is connected to a second photodetector 92, the first photodetector 91 and the second photodetector 92 are both connected to an oscilloscope 93, and the oscilloscope 93 is configured to output time-domain waveforms detected by the first photodetector 91 and the second photodetector 92; the input of coupler 90 is connected to the second end of first circulator 30, the first output of coupler 90 is connected to the input of first filter 50, the second output is connected to spectrometer 94, and spectrometer 94 is used to measure the output spectrum of the second output of coupler 90.
It can be understood that, in order to verify whether the light soliton generation system provided by the embodiment of the present invention generates dissipation kerr solitons, a test is required, and whether light solitons are generated can be determined by observing the time domain waveform of the oscilloscope 93 and the spectrum measured by the spectrometer 94. In specific implementation, the coupler 90 may select a splitting ratio of the first output end to the second output end as 90: 10, and the embodiments of the present invention do not limit this.
Fig. 7 is a schematic structural diagram of another optical soliton generation system according to an embodiment of the present invention. Referring to fig. 7, optionally, the first filter 50 includes a fiber bragg grating for reflecting the pump light and the backward brillouin laser light, and transmitting the dissipative kerr solitons; the optical soliton generation system further includes a second circulator 31, a first end of the second circulator 31 is connected to the first output end of the coupler 90, a second end of the second circulator 31 is connected to the input end of the first filter 50, and a third end of the second circulator 31 is connected to the spectrometer 94; spectrometer 94 is also used to measure the output spectrum of the third end of second circulator 31.
It should be noted that the foregoing are only exemplary embodiments of the present invention, and in practical implementation, a combination of optical devices may be selected according to actual requirements to meet actual application requirements. Fig. 8 is a schematic structural diagram of another optical soliton generation system according to an embodiment of the present invention, and the present embodiment provides a specific example based on the above embodiment. Referring to fig. 8, the optical soliton generation system includes a wavelength tunable light source 10, an optical amplifier 11, a tunable attenuator 80, a second filter 70, a polarization controller 20, a first circulator 30, an optical fiber 40, a first filter 50, an optical microcavity 60, a coupler 90, a second circulator 31, a first photodetector 91, a second photodetector 92, an oscilloscope 93, and a spectrometer 94. The wavelength-tunable light source 10 is a 1550nm tunable cavity diode laser (ECDL, Toptica CTL1550), the optical amplifier 11 is an erbium-doped fiber amplifier (EDFA), the first filter 50 is a fiber bragg grating FBG, and the optical microcavity 60 is a silicon oxide microdisk cavity with a diameter of 6mm and a thickness of 8 μm. The pump light is amplified by an optical amplifier 11(EDFA), passes through an adjustable attenuator 80(VOA), a second filter 70(TBF), a polarization controller 20(FPC) and a first circulator 30 (circulator) in sequence, and is coupled into the optical microcavity 60 by a tapered fiber. The forward transmitted light is converted into an electrical signal by the first photodetector 91(PD1), and then sent to an oscilloscope 93(OSC) to display the forward transmission spectrum. The backward brillouin laser and optical soliton in the same direction as the pump light are input through the second end of the first circulator 30, and the output of the third end is divided into two paths by the coupler 90. One path enters a spectrometer 94(OSA) to observe the condition of Kerr optical frequency comb; the other path of the reflected pump light and the back brillouin laser light are filtered by the first filter 50(FBG), and then sent to the second photodetector 92(PD2), so as to observe the generation of steps in the reverse transmission spectrum. Wherein the pump light reflected by the first filter 50 and the backward brillouin laser light output from the third terminal of the second circulator 31 can also be received by the spectrometer 94.
In this embodiment, a silicon oxide microdisk cavity with a diameter of 6mm and a thickness of 8 μm is used, and the intrinsic Q values of the pumping mode and the Brillouin mode are 4.81 × 107，8.44×107. The generation process of the optical solitons is as follows:
firstly, running pump light at low power, and scanning laser frequency at the speed of 349 MHz/ms; then two space modes with the frequency interval of about 10.8GHz are found on a forward power transmission spectrum of the oscilloscope, and then the laser power is increased and far exceeds the threshold of Brillouin laser; then continuously adjusting the coupling positions of the VOA, the FPC and the optical microcavity and the optical fiber conical structure to adjust the power and the coupling state of the pump light until an optical frequency comb is observed on a spectrometer and a step-shaped transmission spectrum is observed on an oscilloscope for monitoring a reverse transmission spectrum at the same time, which indicates that an optical soliton is generated; and stopping scanning the laser frequency, and adjusting the frequency to the region where the solitons are generated by manually adjusting the piezoelectric of the laser because the pumping laser frequency region corresponding to the solitons is wider.
Wherein, the frequency interval of pump light frequency and the brillouin laser that backs is about 10.8GHz, and fig. 9 shows that the embodiment of the utility model provides an oscillograph's waveform schematic diagram that an oscilloscope gathered wherein, the forward optical power that pump light transmission spectrum was surveyed for first photoelectric detector 91(PD1), and the reverse optical power that the optical frequency comb transmission spectrum was surveyed for second photoelectric detector 92(PD2) is used for looking for soliton step. It can be seen from fig. 9 that the optical frequency comb transmission spectrum has a significant step shape, which means the generation of optical solitons, and the frequency range of the pump laser light is close to 200MHz when the solitons exist.
Fig. 10 is a schematic diagram of a spectrum of optical solitons collected by a spectrometer according to an embodiment of the present invention. Wherein (a), (b) are multiple solitons, and (c) are single solitons. By fitting the spectral shape of the single soliton to assume sech2The shape is consistent with the description of a single soliton in theory, and the soliton is confirmed to be the single soliton, and the repetition frequency of the soliton is 11.14 GHz. Fig. 11 is a schematic diagram of the spectrum of the pump light collected by the spectrometer and the backward brillouin laser in the embodiment of the present invention, from which it can be known that the optical soliton provided by the embodiment is generated by the brillouin laser.
In the optical soliton generation system provided by this embodiment, a beam of continuous single-frequency pump light is coupled into an on-chip silicon oxide microdisk cavity, and optical solitons are generated in the same cavity by using brillouin laser generated by the optical soliton; and the wide step generated by the Brillouin laser in the same cavity can be used for directly and manually adjusting the laser to generate the optical solitons, a complex frequency or power adjusting method is not needed, and the development of system miniaturization and integration is facilitated.
It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.
Claims (10)
1. An optical soliton generation system is characterized by comprising a wavelength-adjustable light source, a polarization controller, a first circulator, an optical fiber, a first filter and an optical microcavity;
the output end of the wavelength-tunable light source is connected with the input end of the polarization controller, the output end of the polarization controller is connected with the first end of the first circulator, the second end of the first circulator is connected with the optical fiber, and the third end of the first circulator is connected with the input end of the first filter;
the optical fiber extends from the second end of the first circulator to the optical microcavity, the optical fiber extending to the optical microcavity comprises a tapered structure, and the optical fiber is coupled with the optical microcavity through the tapered structure;
the optical microcavity comprises a substrate, a supporting column and a cavity, wherein the supporting column and the cavity are positioned on one side of the substrate;
the wavelength-adjustable light source is used for providing pump light, and the pump light is coupled into the optical fiber after passing through the polarization controller and the first circulator;
the polarization controller is used for adjusting the polarization direction of the pump light so as to adjust the coupling efficiency of the pump light and the optical microcavity;
the pump light is coupled into the optical microcavity through the conical structure, the pump light excites backward Brillouin laser in the optical microcavity, and the backward Brillouin laser generates a four-wave mixing effect in the optical microcavity to generate a dissipative Kerr soliton;
the dissipative Kerr soliton is coupled into the optical fiber, is input from the second end of the first circulator and is output from the third end of the first circulator;
the first filter is used for filtering the pumping light and the backward Brillouin laser to output the dissipative Kerr soliton.
2. The optical soliton generation system of claim 1, further comprising an optical amplifier disposed between the wavelength tunable light source and the polarization controller, the optical amplifier configured to amplify the pump light.
3. The optical soliton generation system of claim 2, wherein the optical amplifier is a semiconductor optical amplifier;
the optical soliton generation system further comprises a first collimator, an optical isolator and a second collimator;
the first collimator, the semiconductor optical amplifier, the optical isolator and the second collimator are sequentially arranged between the wavelength-tunable light source and the polarization controller along a light path;
the input end of the first collimator is coupled with the output end of the wavelength-adjustable light source and is used for collimating the pump light and then inputting the collimated pump light into the semiconductor optical amplifier;
the semiconductor optical amplifier is used for amplifying the pump light;
the optical isolator is used for enabling the amplified pump light to be transmitted in a single direction;
and the output end of the second collimator is connected with the input end of the polarization controller.
4. The optical soliton generation system of claim 2, wherein the optical amplifier is a fiber amplifier;
the wavelength-adjustable light source is connected with the input end of the optical fiber amplifier;
and the output end of the optical fiber amplifier is connected with the polarization controller.
5. The optical soliton generation system of claim 2, further comprising a second filter disposed between the optical amplifier and the polarization controller, the second filter configured to filter out spontaneously emitted light from the optical amplifier.
6. The optical soliton generation system of claim 2, further comprising an adjustable attenuator disposed between the optical amplifier and the polarization controller, the adjustable attenuator configured to adjust an output power of the amplified pump light.
7. The optical soliton generation system according to any one of claims 1 to 6, further comprising a coupler, a first photodetector, a second photodetector, an oscilloscope, and a spectrometer;
the optical fiber extending from the optical microcavity is connected with the first photodetector, the output end of the first filter is connected with the second photodetector, the first photodetector and the second photodetector are both connected with the oscilloscope, and the oscilloscope is used for outputting time domain waveforms detected by the first photodetector and the second photodetector;
the input end of the coupler is connected with the second end of the first circulator, the first output end of the coupler is connected with the input end of the first filter, the second output end of the coupler is connected with the spectrometer, and the spectrometer is used for measuring the output spectrum of the second output end of the coupler.
8. The optical soliton generation system of claim 7, wherein the first filter comprises a fiber Bragg grating configured to reflect the pump light and the back-facing Brillouin laser light and transmit the dissipative Kerr soliton;
the optical soliton generation system further comprises a second circulator, wherein a first end of the second circulator is connected with a first output end of the coupler, a second end of the second circulator is connected with an input end of the first filter, and a third end of the second circulator is connected with the spectrometer;
the spectrometer is further configured to measure an output spectrum of a third end of the second circulator.
9. The optical soliton generation system of claim 1, wherein the wavelength tunable light source is a wavelength tunable laser.
10. The optical soliton generation system of claim 1, wherein the substrate material of the optical microcavity comprises silicon and the material of the cavity comprises silicon dioxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021103466.1U CN212062995U (en) | 2020-06-15 | 2020-06-15 | Optical soliton generating system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021103466.1U CN212062995U (en) | 2020-06-15 | 2020-06-15 | Optical soliton generating system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212062995U true CN212062995U (en) | 2020-12-01 |
Family
ID=73514823
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021103466.1U Active CN212062995U (en) | 2020-06-15 | 2020-06-15 | Optical soliton generating system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212062995U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111600192A (en) * | 2020-06-15 | 2020-08-28 | 南京大学 | Optical soliton generating system |
-
2020
- 2020-06-15 CN CN202021103466.1U patent/CN212062995U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111600192A (en) * | 2020-06-15 | 2020-08-28 | 南京大学 | Optical soliton generating system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111600192A (en) | Optical soliton generating system | |
| US9698559B2 (en) | Optical scanning and imaging systems based on dual pulsed laser systems | |
| US6618531B1 (en) | Variable wavelength short pulse light generating device and method | |
| US8964803B2 (en) | Wavelength sweeping light source and imaging apparatus using the same | |
| US7373086B2 (en) | Standard radio frequency signal generating method and standard radio frequency signal generating device | |
| CN111555099A (en) | Microwave generating system | |
| CN112886367B (en) | Terahertz optoelectronic oscillator and oscillation method | |
| US20180083414A1 (en) | Mode-locked and wavelength tunable optical frequency comb generation through dynamic control of microresonators | |
| WO2002021649A2 (en) | Method and device for generating radiation with stabilized frequency | |
| CN102637990A (en) | Optical fiber amplifying system and optical fiber amplifying method | |
| CN102608825A (en) | Method and system for realizing multi-frequency optical comb | |
| CN212062984U (en) | Microwave generating system | |
| JPH09197449A (en) | Optical pulse generator | |
| CN212062995U (en) | Optical soliton generating system | |
| JP6580554B2 (en) | Generator for at least three coherent laser beams in the infrared and visible regions | |
| Liu et al. | Self-oscillating optical frequency comb based on a Raman-pumped Brillouin optoelectronic oscillator | |
| Wu et al. | Optical frequency comb and picosecond pulse generation based on a directly modulated microcavity laser | |
| Zhang et al. | All-fiber wideband supercontinuum generation in short hybrid highly nonlinear fibers with a femtosecond erbium-doped fiber laser | |
| GOMES | Hybrid electronically addressable random fiber laser | |
| JP2005241732A (en) | Optical pulse amplification apparatus | |
| Galindez et al. | Integral temperature hybrid laser sensor | |
| Evans et al. | Multiwavelength Mode-locked Fiber Ring Laser with a Lyot Filter and a Hybrid Gain Medium | |
| Ismail et al. | Multi-wavelength Brillouin Raman Erbium Fiber Laser utilizing Captured Residual Raman Pump Power | |
| CN115685639A (en) | Octave optical frequency comb generation system | |
| CN117498141A (en) | System and method for generating microcavity Kerr solitons |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |