Monostable single soliton generation system and method

Abstract

The embodiment of the application discloses a monostable single soliton generation system and method. The system comprises a wavelength tunable laser light source, a polarization controller, an optical microcavity, a beam splitter, a filter, an oscilloscope and a spectrometer; the wavelength tunable laser light source outputs pump light, the pump light is coupled into the optical microcavity after the polarization state is adjusted by the polarization controller, the forward light beam output by the optical microcavity is monitored by a first channel of the oscilloscope, the reverse light beam is transmitted to the input end of the beam splitter, the light beam output by the first output end of the beam splitter is monitored by a second channel of the oscilloscope, the light beam output by the second output end is monitored by a third channel of the oscilloscope after passing through the filter, and the light beam output by the third output end is monitored by the spectrometer. The technical scheme of the embodiment of the application can directly enter a single soliton state only by simply adjusting pump detuning in one direction, and greatly simplifies the complex operation required for generating a single soliton at present.

Description

Technical Field

[0001] This invention relates to the field of laser technology, and in particular to a monostable single soliton generation system and method. Background Technology

[0002] Each comb tooth in a single soliton is coherent, exhibiting excellent noise performance, and possesses a fixed spectral envelope and repetition frequency interval. This deterministic characteristic allows it to have a wider range of applications than multi-solitons.

[0003] In optical microcavities, solitons are typically generated in the red detuning region of the cavity mode resonance. However, the red detuning region is thermally unstable, making it difficult to maintain stable laser output. While some existing techniques can overcome the thermo-optical effects of optical microcavities, enabling stable soliton generation in the red detuning region, these techniques cannot definitively generate single solitons directly. Furthermore, after generating multiple solitons, the detuning of the pump laser needs to be tuned forward or backward to gradually degenerate from the multiple soliton state to the single soliton state. This method of generating single solitons is quite complex.

[0004] "Turnkey" operation refers to a technique that can directly generate solitons by turning on the laser. Currently, this can be achieved through self-injection locking, but the self-injection locking technique itself is quite complex, making it difficult to promote and apply single soliton generation systems. Summary of the Invention

[0005] This invention provides a monostable soliton generation system and method. This system allows direct entry into the soliton state simply by unidirectionally adjusting the pump detuning, greatly simplifying the complex operations currently required for soliton generation. Based on this monostable soliton, self-injection locking can be eliminated, and the "keying" operation can be completed directly, significantly facilitating the widespread adoption and application of microcavity soliton optical frequency combs.

[0006] According to one aspect of the present invention, a monostable single soliton generation system is provided, comprising a wavelength-tunable laser source, a polarization controller, an optical microcavity, a beam splitter, a filter, an oscilloscope, and a spectrometer;

[0007] The wavelength-tunable laser source is used to output pump light. The pump light is coupled into the optical microcavity after its polarization state is adjusted by the polarization controller. The forward beam output by the optical microcavity is monitored by the first channel of the oscilloscope. The reverse beam output by the optical microcavity is transmitted to the input end of the beam splitter. The beam output by the first output end of the beam splitter is monitored by the second channel of the oscilloscope. The beam output by the second output end of the beam splitter is monitored by the third channel of the oscilloscope after passing through the filter. The beam output by the third output end of the beam splitter is monitored by the spectrometer.

[0008] The frequency of the pump light output from the wavelength-tunable laser source is scanned, while the polarization state of the pump light is adjusted. The Brillouin laser of the second channel of the oscilloscope is monitored, and the optical frequency comb on the spectrometer is monitored.

[0009] By adjusting the polarization state of the pump light and the coupling state between the pump light and the optical microcavity, so that soliton steps appear directly after the Brillouin laser during the pump scanning process;

[0010] Turn off the scanning signal of the pump light frequency, and manually adjust the frequency of the pump light so that the pump light falls within the soliton step range;

[0011] The drive current of the wavelength-tunable laser source is scanned from zero until the maximum current is reached just in time to sweep through the soliton mode. Then, the stop value of the drive current is adjusted so that the Brillouin laser frequency falls exactly in the red detuned region where solitons are generated when the scan stops, and a monostable single soliton is output.

[0012] Optionally, it may also include a first photodetector, a second photodetector, and a third photodetector;

[0013] The first photodetector is connected to the first channel of the oscilloscope and is used to receive the positive beam output by the optical microcavity;

[0014] The second photodetector is connected to the second channel of the oscilloscope and is used to receive the light beam output from the first output terminal of the beam splitter;

[0015] The third photodetector is connected to the third channel of the oscilloscope and is used to receive the beam output by the filter.

[0016] Optionally, it also includes a circulator and a first optical fiber, the first optical fiber including a tapered structure, the first optical fiber being coupled to the optical microcavity through the tapered structure, a first end of the circulator for receiving the pump light, a second end of the circulator being connected to one end of the first optical fiber, and a third end of the circulator for outputting a reverse beam.

[0017] Optionally, it also includes a second optical fiber and a third optical fiber, both of which include a tapered structure. The tapered structure of the second optical fiber and the tapered structure of the third optical fiber form a double-sided coupling structure with the optical microcavity. The second optical fiber is used to receive the pump light, and the third optical fiber is used to output a reverse beam.

[0018] Optionally, the conical structure and the optical microcavity are cured with UV-curable adhesive and encapsulated in a sealed container.

[0019] Optionally, the optical microcavity includes a substrate and a support pillar and cavity located on one side of the substrate.

[0020] Optionally, the cavity may include a microcolumn cavity, a microring core cavity, a microdisc cavity, or a microsphere cavity.

[0021] Optionally, the substrate and the support pillar comprise silicon, and the cavity comprises aluminum nitride, silicon nitride, magnesium fluoride, barium fluoride, lithium niobate, or silicon carbide.

[0022] Optionally, the wavelength-tunable laser source includes a tunable cavity diode laser.

[0023] According to another aspect of the present invention, a method for generating a monostable soliton is provided, wherein a monostable soliton is output from the above-described monostable soliton generation system, the method comprising:

[0024] The frequency of the pump light output from the wavelength-tunable laser source is scanned, and the polarization state of the pump light is adjusted. The Brillouin laser in the second channel of the oscilloscope is monitored, and the optical frequency comb on the spectrometer is also monitored.

[0025] By adjusting the polarization state of the pump light and the coupling state between the pump light and the optical microcavity, so that soliton steps appear directly after the Brillouin laser during the pump scanning process;

[0026] Turn off the scanning signal of the pump light frequency, and manually adjust the frequency of the pump light so that the pump light falls within the soliton step range;

[0027] The drive current of the wavelength-tunable laser source is scanned from zero so that the maximum current is reached just in time to sweep through the soliton mode.

[0028] Adjust the stop value of the driving current so that when the scanning stops, the Brillouin laser frequency falls exactly in the red detuning region where solitons are generated, and output a monostable single soliton.

[0029] The monostable single soliton generation system provided in this embodiment of the invention includes a wavelength-tunable laser source, a polarization controller, an optical microcavity, a beam splitter, a filter, an oscilloscope, and a spectrometer. The wavelength-tunable laser source is used to output pump light. After the polarization state of the pump light is adjusted by the polarization controller, it is coupled into the optical microcavity. The forward beam output by the optical microcavity is monitored by the first channel of the oscilloscope, and the reverse beam output by the optical microcavity is transmitted to the input end of the beam splitter. The beam output from the first output end of the beam splitter is monitored by the second channel of the oscilloscope. The beam output from the second output end of the beam splitter is monitored by the third channel of the oscilloscope after passing through the filter. The beam output from the third output end of the beam splitter is monitored by the spectrometer. First, the frequency of the pump light output from the wavelength-tunable laser source is scanned, while the polarization state of the pump light is adjusted. The Brillouin laser on the second channel of the oscilloscope is monitored, along with the optical frequency comb on the spectrometer. Then, the polarization state of the pump light and the coupling state between the pump light and the optical microcavity are adjusted so that a soliton step appears directly after the Brillouin laser during the pump scan. Next, the pump light frequency scanning signal is turned off, and the pump light frequency is manually adjusted so that the pump light falls within the soliton step range. The driving current of the wavelength-tunable laser source is scanned from zero so that the maximum current just sweeps through the soliton mode. Then, the stop value of the driving current is adjusted so that the Brillouin laser frequency falls exactly in the red detuning region where the soliton is generated when the scan stops, outputting a monostable single soliton. The technical solution of this embodiment of the invention only requires simple unidirectional adjustment of the pump detuning to directly enter the single soliton state, which greatly simplifies the complex operation currently required to generate single solitons. Based on this monostable single soliton, the "keying" operation can be completed directly without self-injection locking, greatly facilitating the popularization and application of microcavity soliton optical frequency combs.

[0030] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of a monostable single soliton generation system provided in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of another monostable single soliton generation system provided in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of an optical microcavity structure provided in an embodiment of the present invention;

[0035] Figure 4 This is a waveform diagram of an oscilloscope during the adjustment process of a monostable single soliton generation system provided in an embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram of the spectrum of a monostable single soliton output by an embodiment of the present invention;

[0037] Figure 6 This is a schematic diagram of the oscilloscope waveform when outputting a monostable single soliton in an embodiment of the present invention;

[0038] Figure 7 This is a schematic diagram of the oscilloscope waveform when scanning the drive current according to an embodiment of the present invention.

[0039] Figure 8 A schematic diagram of the "key activation" process of a monostable single soliton generation system provided in an embodiment of the present invention.

[0040] Figure 9 This is a flowchart illustrating a method for generating a monostable single soliton according to an embodiment of the present invention. Detailed Implementation

[0041] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0042] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0043] Currently, there are several main methods for generating Kerr microcavity soliton optical frequency combs: power kicking, assisted-pump laser, single-sideband modulation, and Brillouin-Kerr soliton technology. In power kicking, an acousto-optic modulator is used to reduce the pump power before the laser is tuned to resonance. The pump power is increased within the soliton step size at the end of the resonant thermal triangle, making the drift of the resonant cavity mode in the soliton state approximately equal to the thermal drift in the modulation instability state. This method of generating solitons requires extremely high precision in various parameters and cannot accurately reach a single soliton state. In assisted-pump laser technology, an external auxiliary laser is needed to stabilize the cavity power to overcome the thermo-optic effect. The pump laser can then be manually tuned to a soliton state, but the soliton state entered is uncertain, requiring further fine-tuning of the pump detuning to reach a single soliton state. In single-sideband modulation (SSM), solitons are generated by precisely adjusting the sweep rate to control the thermal drift of the microcavity. The number of solitons generated by this method is typically uncertain; however, through continuous optimization of various adjustment parameters, the probability of generating a single soliton eventually reaches 96%. In Brillouinkel soliton technology, the characteristic that the Brillouin frequency changes with the pump frequency is utilized. By tuning the pump wavelength, the detuning of the Brillouin laser is altered. The pump itself plays a role in stabilizing the intracavity power at the blue detuning point. This method initially generates multiple solitons, but further tuning of the pump frequency is required to enter the single soliton state.

[0044] The existing methods for generating single solitons cannot generate single solitons deterministically. Single-sideband modulation and power kicking techniques require external modulators, auxiliary pump lasers require two lasers, existing Brillouin soliton schemes also require optical amplifiers, and existing "key-on" operation systems require self-injection locking, which leads to complex system structures.

[0045] To address the complexities of single soliton generation, this invention provides a monostable single soliton generation system. This system eliminates the need for modulators and amplifiers, requiring only a single laser to deterministically generate single solitons. Furthermore, compared to existing "keying" techniques, this monostable single soliton does not require self-injection locking to achieve the "keying" operation.

[0046] Figure 1 This is a schematic diagram of a monostable single soliton generation system provided in an embodiment of the present invention, with reference to... Figure 1The monostable single soliton generation system includes a wavelength-tunable laser source 10, a polarization controller 20, an optical microcavity 30, a beam splitter 40, a filter 50, an oscilloscope 60, and a spectrometer 70. The wavelength-tunable laser source 10 outputs pump light. After the polarization state of the pump light is adjusted by the polarization controller 20, it is coupled into the optical microcavity 30. The forward beam output from the optical microcavity 30 is monitored by the first channel of the oscilloscope 60. The reverse beam output from the optical microcavity 30 is transmitted to the input of the beam splitter 40. The beam output from the first output of the beam splitter 40 is monitored by the second channel of the oscilloscope 60. The beam output from the second output of the beam splitter 40 is monitored by the third channel of the oscilloscope 60 after passing through the filter 50. The beam output from the third output of the beam splitter 60 is monitored by the spectrometer 70. The frequency of the pump light output from the wavelength-tunable laser source 10 is scanned, and the frequency is simultaneously adjusted... The polarization state of the pump light is monitored by the Brillouin laser in the second channel of the oscilloscope 60, and the optical frequency comb on the spectrometer 70 is also monitored. The polarization state of the pump light and the coupling state between the pump light and the optical microcavity 30 are adjusted so that a soliton step appears directly after the Brillouin laser during the pump scanning process. The pump light frequency scanning signal is turned off, and the pump light frequency is manually adjusted so that the pump light falls within the soliton step range. The driving current of the wavelength-tunable laser source 10 is scanned from zero so that the maximum current is reached just in time to sweep through the soliton mode. Then the stop value of the driving current is adjusted so that the Brillouin laser frequency falls exactly in the red detuning region where solitons are generated when the scanning stops, and a monostable single soliton is output.

[0047] Optionally, the wavelength-tunable laser source 10 includes a tunable cavity diode laser (ECDL). The pump light output from the wavelength-tunable laser source 10 is coupled into the optical microcavity 30 after the polarization state is adjusted by the polarization controller 20. The optical microcavity 30 can be a microcylinder cavity, microring cavity, microdisk cavity, or microsphere cavity, etc., and can be selected according to the actual situation in specific implementation. The beam splitter 40 can be a 1×3 fiber coupler, used to split the reverse beam of the optical microcavity 30 into three beams. The first beam is received by the second channel of the oscilloscope 60 to detect the change in total power in the reverse cavity. The second beam is filtered by the filter 50 and received by the third channel of the oscilloscope 60 to detect the change in optical comb power. The third beam is received by the spectrometer 70. The filter 50 can be a fiber Bragg grating filter, used to filter out the pump light and Brillouin laser.

[0048] The working process of the monostable single soliton generation system provided in this embodiment of the invention is as follows:

[0049] 1. First, optical microcavity samples are screened. In this embodiment, to generate monostable solitons, the soliton modes should have a high quality factor. In a specific embodiment, the quality factor of the optical microcavity is 4 × 10⁻⁶. 8 .

[0050] 2. The tunable cavity diode laser outputs 30mW of power and is equipped with an external scanning signal that scans the laser frequency from short wave to long wave. The external signal is a triangular wave with an amplitude of 2Vpp and a frequency of 10Hz.

[0051] 3. By adjusting the pump light frequency and changing the polarization, the Brillouin laser can be seen being excited on the first channel of the oscilloscope, and an optical comb is generated on the spectrometer.

[0052] 4. Optimize the coupling position and polarization to make a typical soliton step appear directly after the Brillouin laser during the pump scanning process.

[0053] 5. Turn off the external scanning signal and manually adjust the pump frequency to ensure the pump falls within the step range. Typical single soliton sech can be observed on the spectrometer. 2 The spectrum of the envelope is shown, while the power on the oscilloscope remains a straight line.

[0054] 6. The laser current was scanned from zero until the maximum current was reached just in time to sweep through the soliton mode. Then the stop value of the current was adjusted so that the frequency fell exactly in the red detuning region where the soliton was generated when the scan stopped. This proved that this monostable single soliton can achieve the "keying" operation.

[0055] The technical solution of this invention allows direct entry into a single soliton state with simple unidirectional pump detuning, greatly simplifying the complex operations currently required for generating single solitons. Based on this monostable single soliton, the "keying" operation can be completed directly without self-injection locking, greatly facilitating the popularization and application of microcavity soliton optical frequency combs.

[0056] Continue to refer to Figure 1 Optionally, the monostable single soliton generation system further includes a first photodetector 81, a second photodetector 82, and a third photodetector 83; the first photodetector 81 is connected to the first channel of the oscilloscope 60 and is used to receive the forward beam output from the optical microcavity 30; the second photodetector 82 is connected to the second channel of the oscilloscope 60 and is used to receive the beam output from the first output terminal of the beam splitter 40; the third photodetector 83 is connected to the third channel of the oscilloscope 60 and is used to receive the beam output from the filter 50.

[0057] Understandably, the oscilloscope 60 cannot directly process optical signals. Instead, it converts the optical signals into electrical signals using a photodetector, which are then analyzed and processed by the oscilloscope 60.

[0058] Continue to refer to Figure 1 Optionally, the monostable single soliton generation system also includes a circulator 90 and a first optical fiber 100, the first optical fiber 100 including a tapered structure ( Figure 1(Not shown in the image), the first optical fiber 100 is coupled to the optical microcavity 30 through a tapered structure, the first end of the circulator 90 is used to receive pump light, the second end of the circulator 90 is connected to one end of the first optical fiber 100, and the third end of the circulator 90 is used to output a reverse beam.

[0059] A circulator is a multi-port optical device with non-reciprocal characteristics. When an optical signal is input through any port, it is output from the next port in digital order with very little loss. If a signal is input through port 1, the signal can only be output through port 2; similarly, a signal input through port 2 can only be output through port 3, and so on. In practice, all optical components in the system can be connected via optical fibers.

[0060] Figure 2 This is a schematic diagram of another monostable single soliton generation system provided in an embodiment of the present invention, with reference to... Figure 2 Optionally, the monostable single soliton generation system also includes a second optical fiber 110 and a third optical fiber 120, both of which include a tapered structure. Figure 2 (Not shown in the image), the tapered structure of the second optical fiber 110 and the tapered structure of the third optical fiber 120 form a double-sided coupling structure with the optical microcavity 30. The second optical fiber 110 is used to receive pump light, and the third optical fiber 130 is used to output a reverse beam.

[0061] It is understood that in this embodiment, two parallel fiber tapers are used through a double-sided coupling (Add-Drop) structure to couple a single soliton at the other end of the optical microcavity, replacing the circulator in the experimental system. The principle of optical soliton generation is the same as... Figure 1 The principle is the same. In other embodiments, other coupling methods can be used to generate monostable photonics, such as waveguide coupling.

[0062] Optionally, the conical structure and optical microcavity are cured with UV-curable adhesive and encapsulated in a sealed container.

[0063] If the coupling between the conical structure and the optical microcavity is cured by UV-curing adhesive, the coupling will not change due to external vibrations, further improving the long-term stability of the soliton. If the optical microcavity is encapsulated in a well-sealed container with good airtightness, the optical mode quality factor of the optical microcavity will not decrease due to external contamination such as water vapor and dust, giving the system an extremely long service life. In this embodiment, the UV-curing adhesive can be used for curing after the experiment has been adjusted to the optimal position.

[0064] Figure 3 This is a schematic diagram of an optical microcavity provided in an embodiment of the present invention. (Reference) Figure 3Optionally, the optical microcavity includes a substrate 31, a support pillar 32 located on one side of the substrate 31, and a cavity 33. In specific implementations, the cavity 33 may optionally include a micropillar cavity, a microring cavity, a microdisc cavity, or a microsphere cavity. Figure 3 The illustration shows cavity 33 as a microdisk cavity, which is not intended to limit the embodiments of the present invention. Both substrate 31 and support pillar 32 can be made of silicon, and cavity 33 can include aluminum nitride, silicon nitride, magnesium fluoride, barium fluoride, lithium niobate, or silicon carbide.

[0065] Figure 4 This is a waveform diagram from an oscilloscope during the adjustment process of the monostable single soliton generation system provided in an embodiment of the present invention. The blue line represents the power change of the forward beam, the green line represents the power change of the reverse beam, and the red line represents the power change of the soliton comb. Figure 4 It can be seen that the Brillouin laser directly enters the soliton state.

[0066] Manually tune the laser to enter the soliton state. Figure 5 This is a schematic diagram of the spectrum of a monostable single soliton output by an embodiment of the present invention. Figure 6 This is a schematic diagram of the oscilloscope waveform when outputting a monostable single soliton according to an embodiment of the present invention. Figure 5 It can be seen that the spectral envelope observed on the spectrometer does indeed conform to sech squared, where the inset represents the beat frequency signal. Figure 6 It can be seen that the power on the oscilloscope is stable, and the generated soliton can be confirmed to be a single soliton state by the width of the spectral signal, power signal and beat frequency signal linewidth.

[0067] Scan the drive current from zero. Figure 7 This is a waveform diagram of an oscilloscope during scanning of the drive current according to an embodiment of the present invention. Figure 7 It can be seen that when the laser sweeps through the soliton mode, there is a distinct soliton step, where the blue line represents the power change of the forward beam and the red line represents the power change of the optical comb. Adjusting the scanning cutoff current so that the laser falls precisely within the step... Figure 8 This is a schematic diagram of the "key-on" process of a monostable single soliton generation system provided in an embodiment of the present invention, where the red line represents the drive current and the blue line represents the oscilloscope waveform. Figure 8 As can be seen, the monostable soliton system provided in this embodiment of the invention can realize the "keying" operation of generating monostable solitons by directly turning on the laser.

[0068] The technical solution of this invention uses a continuous beam of light to pump a high-quality factor microcavity to generate Brillouin laser, and this Brillouin laser deterministically generates a single soliton in the same high-quality factor microcavity. The generation probability of this single soliton is 100%. This monostable single soliton has low power consumption, does not require an amplifier, and can enter the single soliton state simply by unidirectional frequency sweep. This feature makes it easy to implement the "keying" operation.

[0069] Figure 9 This is a flowchart illustrating a method for generating a monostable solito according to an embodiment of the present invention. The method generates a monostable solito by outputting a monostable solito from any of the monostable solito generation systems provided in the above embodiments. The method includes:

[0070] S110: Scan the frequency of the pump light output from the wavelength-tunable laser source, adjust the polarization state of the pump light, monitor the Brillouin laser in the second channel of the oscilloscope, and monitor the optical frequency comb on the spectrometer.

[0071] S120 adjusts the polarization state of the pump light and the coupling state between the pump light and the optical microcavity so that a soliton step appears directly after the Brillouin laser during the pump scanning process.

[0072] S130. Turn off the scanning signal of the pump light frequency and manually adjust the frequency of the pump light so that the pump light falls within the soliton step range.

[0073] S140: Scan the drive current of the wavelength-tunable laser source from zero so that the maximum current is reached just in time to sweep through the soliton mode.

[0074] S150: Adjust the stop value of the drive current so that when the scan stops, the Brillouin laser frequency falls exactly in the red detuning region where solitons are generated, and outputs a monostable single soliton.

[0075] The technical solution of this invention allows direct entry into a single soliton state with simple unidirectional pump detuning, greatly simplifying the complex operations currently required for generating single solitons. Based on this monostable single soliton, the "keying" operation can be completed directly without self-injection locking, greatly facilitating the popularization and application of microcavity soliton optical frequency combs.

[0076] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A monostable single soliton generation system, characterized in that, This includes wavelength-tunable laser sources, polarization controllers, optical microcavities, beam splitters, filters, oscilloscopes, and spectrometers; The wavelength-tunable laser source is used to output pump light. The pump light is coupled into the optical microcavity after its polarization state is adjusted by the polarization controller. The forward beam output by the optical microcavity is monitored by the first channel of the oscilloscope. The reverse beam output by the optical microcavity is transmitted to the input end of the beam splitter. The beam output by the first output end of the beam splitter is monitored by the second channel of the oscilloscope to detect the change in total power in the reverse cavity. The beam output by the second output end of the beam splitter is monitored by the third channel of the oscilloscope after passing through the filter to detect the change in optical comb power. The beam output by the third output end of the beam splitter is monitored by the spectrometer. The frequency of the pump light output from the wavelength-tunable laser source is scanned, while the polarization state of the pump light is adjusted. The Brillouin laser of the second channel of the oscilloscope is monitored, and the optical frequency comb on the spectrometer is monitored. By adjusting the polarization state of the pump light and the coupling state between the pump light and the optical microcavity, so that soliton steps appear directly after the Brillouin laser during the pump scanning process; The pump light frequency scanning signal was turned off, and the pump light frequency was manually adjusted so that it fell within the soliton step range. Typical single soliton sech was observed on the spectrometer. 2 The spectrum of the envelope, while the power on the oscilloscope remains a straight line; The drive current of the wavelength-tunable laser source is scanned from zero until the maximum current is reached just in time to sweep through the soliton mode. Then, the stop value of the drive current is adjusted so that the Brillouin laser frequency falls exactly in the red detuned region where solitons are generated when the scan stops, and a monostable single soliton is output.

2. The monostable single soliton generation system according to claim 1, characterized in that, It also includes a first photodetector, a second photodetector, and a third photodetector; The first photodetector is connected to the first channel of the oscilloscope and is used to receive the positive beam output by the optical microcavity; The second photodetector is connected to the second channel of the oscilloscope and is used to receive the light beam output from the first output terminal of the beam splitter; The third photodetector is connected to the third channel of the oscilloscope and is used to receive the beam output by the filter.

3. The monostable single soliton generation system according to claim 1, characterized in that, It also includes a circulator and a first optical fiber, the first optical fiber having a tapered structure, the first optical fiber being coupled to the optical microcavity through the tapered structure, the first end of the circulator being used to receive the pump light, the second end of the circulator being connected to one end of the first optical fiber, and the third end of the circulator being used to output a reverse beam.

4. The monostable single soliton generation system according to claim 1, characterized in that, It also includes a second optical fiber and a third optical fiber, both of which have a tapered structure. The tapered structures of the second and third optical fibers form a double-sided coupling structure with the optical microcavity. The second optical fiber is used to receive the pump light, and the third optical fiber is used to output a reverse beam.

5. The monostable single soliton generation system according to claim 3 or the present invention, characterized in that, The conical structure and the optical microcavity are cured with UV-curing adhesive and encapsulated in a sealed container.

6. The monostable single soliton generation system according to claim 1, characterized in that, The optical microcavity includes a substrate and a support pillar and cavity located on one side of the substrate.

7. The monostable single soliton generation system according to claim 6, characterized in that, The cavity includes a microcolumn cavity, a microring core cavity, a microdisc cavity, or a microsphere cavity.

8. The monostable single soliton generation system according to claim 6, characterized in that, The substrate and the support pillars comprise silicon, and the cavity comprises aluminum nitride, silicon nitride, magnesium fluoride, barium fluoride, lithium niobate, or silicon carbide.

9. The monostable single soliton generation system according to claim 1, characterized in that, The wavelength-tunable laser source includes a tunable cavity diode laser.

10. A method for generating a monostable single soliton, characterized in that, The monostable soliton generation system according to any one of claims 1 to 9 outputs a monostable soliton, wherein the monostable soliton generation method comprises: The frequency of the pump light output from the wavelength-tunable laser source is scanned, and the polarization state of the pump light is adjusted. The Brillouin laser in the second channel of the oscilloscope is monitored, and the optical frequency comb on the spectrometer is also monitored. By adjusting the polarization state of the pump light and the coupling state between the pump light and the optical microcavity, so that soliton steps appear directly after the Brillouin laser during the pump scanning process; The pump light frequency scanning signal was turned off, and the pump light frequency was manually adjusted so that it fell within the soliton step range. Typical single soliton sech was observed on the spectrometer. 2 The spectrum of the envelope, while the power on the oscilloscope remains a straight line; The drive current of the wavelength-tunable laser source is scanned from zero so that the maximum current is reached just in time to sweep through the soliton mode. Adjust the stop value of the driving current so that when the scanning stops, the Brillouin laser frequency falls exactly in the red detuning region where solitons are generated, and output a monostable single soliton.

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