An integrated fast tunable narrow linewidth laser array source based on AWG and single micro-ring time division multiplexing

Abstract

The application discloses an integrated fast tunable narrow linewidth laser array light source based on AWG and single micro-ring time division multiplexing, which comprises a laser array, a driving control circuit, an arrayed waveguide grating (AWG), a common bus waveguide, a single micro-ring external cavity and an output light path, and can realize output control of any wavelength in a target wavelength range. Specifically, the driving control circuit is used for electrically gating the laser array according to preset time slots, so that only one laser outputting a target wavelength is output at the same time, wavelength switching is realized, and then wavelength tuning is realized; any wavelength of the laser array enters the common bus waveguide after the AWG and is coupled with the same micro-ring external cavity, a resonance enhanced light field is formed in the micro-ring, and the linewidth of any laser wavelength is narrowed. The application realizes sharing of any wavelength switching of multi-channel lasers by using a single micro-ring, reduces the number of devices and the system complexity, and is suitable for a multi-channel narrow linewidth light source integrated system.

Description

Technical Field

[0001] This invention relates to the field of semiconductor laser arrays and integrated photonic devices, and in particular to an integrated fast tunable narrow linewidth laser array light source based on AWG and single microring time-division multiplexing, which can achieve fast tunable narrow linewidth output within the target wavelength range. Background Technology

[0002] With the development of multi-channel optical interconnects, coherent communication, on-chip light source arrays, and highly integrated optoelectronic systems, the demand for narrow-linewidth, multi-wavelength, and low-complexity laser source systems is constantly increasing. Although traditional laser arrays can provide multi-channel output, their linewidth is usually wide, and their frequency stability and coherence are limited, making it difficult to meet the requirements of high-performance optical interfaces and high-coherence applications.

[0003] Optical interfaces, with their high bandwidth, low latency, low power consumption, and resistance to electromagnetic interference, can significantly improve the data transmission efficiency of high-performance AI chips. Optical interfaces can achieve transmission rates exceeding 100Gbps per channel, effectively supporting high-speed communication between chips and overcoming the performance limitations of electrical interfaces. However, the performance of optical interfaces is highly dependent on the quality of the light source. For high-performance AI chip optical interfaces, the light source needs to have narrow linewidth characteristics. Narrow linewidth light sources can reduce dispersion and crosstalk during signal transmission, ensuring the stability of long-distance, high-speed data transmission, thereby improving the reliability of the entire optical communication link.

[0004] The technology of fast, tunable, narrow-linewidth laser arrays based on microring external cavity structures has emerged. Microring resonators possess extremely high quality factors and can generate strong resonance for specific wavelengths of light. By precisely designing and controlling the structural parameters of the microring external cavity, accurate selection of the laser output wavelength can be achieved, compressing the linewidth to the sub-kHz level and greatly improving the monochromaticity and coherence of the light source. Due to their advantages of small size, high quality factor, and ease of integration, microring resonators are widely used for filtering, frequency selection, feedback, and linewidth narrowing. However, most existing multi-channel narrow-linewidth solutions employ a structure of "one microring per laser" or "multiple microrings operating in parallel," resulting in a large number of components, complex control, significant thermal crosstalk, and high system area and cost.

[0005] Therefore, it is necessary to propose a system architecture that can achieve multi-channel laser sharing, arbitrary and rapid switching within the target wavelength range, and narrow linewidth output with fewer micro-ring devices, in order to reduce complexity and improve integration. Summary of the Invention

[0006] The problem to be solved by this invention is to provide an integrated fast tunable narrow linewidth laser array light source based on AWG and single microring time-division multiplexing, so as to solve the problems of large number of microrings, complex control and insufficient integration in existing multi-channel narrow linewidth laser systems.

[0007] The present invention adopts the following technical solution: an integrated fast tunable narrow linewidth laser array light source based on AWG and single microring time division multiplexing, comprising: laser array, driving control circuit, arrayed waveguide grating (AWG), common bus waveguide, single microring external cavity and output optical path.

[0008] The laser array includes N tunable lasers, each of which is connected to each input terminal of the AWG, for providing laser output of any target wavelength within the target wavelength range;

[0009] The common terminal of the AWG is coupled to the external cavity of a single microring via a common bus waveguide;

[0010] The drive control circuit is used to poll and select the current working channel according to a preset time slot, so that only one laser outputs the target wavelength at any given time, thereby achieving rapid and stable wavelength switching.

[0011] The laser from the current working channel enters the common bus waveguide after being forward multiplexed by the AWG and resonantly couples with the outer cavity of the micro-ring.

[0012] When the resonant wavelength of the micro-ring outer cavity matches the laser wavelength of the current working channel, the micro-ring outer cavity performs frequency selectivity on the input laser, narrowing the laser linewidth.

[0013] Furthermore, the laser array is an 8-channel tunable DFB laser array, with the center wavelengths of each channel arranged at preset intervals, and it integrates a Y-multiplexer and a TEC temperature control unit.

[0014] Furthermore, the resonant wavelength λ of the single microring external cavity res satisfy:

[0015] ;

[0016] In the formula, It is the effective refractive index of the waveguide. It is the radius of the micro-ring. It is the order of the resonant mode.

[0017] The current working laser output wavelength and λ res During matching, the phases of light propagating in each ring of the microring are superimposed and enhanced, thus forming a resonant light field within the ring. If the wavelength deviates from the resonance condition, the light field cannot be continuously enhanced, and the selective effect of the microring on that frequency component weakens.

[0018] Furthermore, the quality factor of the single microring external cavity is used to characterize its frequency selectivity, and the quality factor of the microring resonator... Defined as the ratio of the resonant frequency to the full width at half maximum (FWHM) of the resonant peak:

[0019] ;

[0020] in, It is the full width at half maximum (FWHM) wavelength of the resonance peak.

[0021] higher The value implies a sharper resonance peak and a narrower effective filtering bandwidth, which enables more effective suppression of non-resonant frequency components and improves the frequency selectivity of the micro-ring external cavity for the current working laser.

[0022] Furthermore, the free spectral range (FSR) of the microring resonator is defined as the wavelength interval between two adjacent resonant peaks:

[0023] ;

[0024] in, For group refractive index, The resonant wavelength; The free spectral range is used to describe the periodic resonant mode spacing provided by a single microring within a certain wavelength range.

[0025] The present invention preferably designs the FSR to be equal to or nearly equal to the channel spacing of the laser array. For example, for an 8-channel laser array with a wavelength spacing of 0.8 nm, the single microring FSR is designed to be approximately 0.8 nm. In this way, each microring naturally has a resonant comb structure that matches the array channel period within the target wavelength range. This allows the currently selected target wavelength to couple with the corresponding resonant mode of the single microring's external cavity when the laser array performs rapid target wavelength switching, thereby achieving shared linewidth narrowing for multiple target wavelengths.

[0026] Furthermore, the drive control circuit uses logic gates to implement time slot selection, so that only one laser can output a beam at any given time, thereby achieving rapid and stable switching of the laser array within the target wavelength range.

[0027] Furthermore, the output optical path is connected to the transmission end of the common bus waveguide and / or the output end of the micro-ring outer cavity, and is used to output narrow linewidth laser corresponding to the currently selected target wavelength.

[0028] Furthermore, the outer cavity of the microring is a silicon-based microring outer cavity, manufactured based on silicon-based semiconductor technology.

[0029] As a further improvement of the present invention, the present invention adopts an electrical gating method to realize time-division multiplexing polling, and uses a logic control circuit to open the laser path corresponding to the current working channel, while the other channels are in a closed state.

[0030] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0031] 1. Through a single high The micro-ring external cavity shares multiple target wavelength laser channels, significantly reducing the number of micro-ring devices and lowering system area and thermal control complexity.

[0032] 2. By matching the FSR with the channel spacing, the adaptability of a single microring to the laser array channel spacing is improved, enabling a single microring to serve the multi-wavelength linewidth narrowing requirements within the target wavelength range.

[0033] 3. By using electrical gating control, the wavelength switching capability of the laser array is improved to be fast and stable.

[0034] 4. The silicon-based microring outer cavity of this invention is based on mature silicon-based semiconductor technology, which is easy to integrate and greatly reduces the volume of systems with the same number of wavelengths. This invention has advantages in materials and manufacturing costs, which is conducive to large-scale production and application promotion. Attached Figure Description

[0035] Figure 1 This is a structural diagram of a fast tunable narrow linewidth laser array source chip for time-division multiplexing of a single micro-ring, according to an embodiment of the present invention.

[0036] Figure 2 This is a schematic diagram of a fast tunable narrow linewidth laser array light source system with single micro-ring time-division multiplexing according to an embodiment of the present invention;

[0037] Figure 3 This is a structural diagram of a fast tunable narrow-linewidth laser array source system with single micro-ring time-division multiplexing according to an embodiment of the present invention;

[0038] Figure 4 This is a graph showing the external output characteristics of the silicon-based microring according to an embodiment of the present invention.

[0039] Figure 5 The image shows the output spectrum of an eight-channel fast tunable narrow linewidth laser array source chip based on a single microring, according to an embodiment of the present invention, under polling illumination. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the application will be further described in detail below with reference to the accompanying drawings. The described embodiments are only a part of the embodiments involved in this invention. All non-innovative embodiments based on these embodiments by other researchers in the art are within the protection scope of this invention. Furthermore, the step numbers in the embodiments of this invention are only set for ease of explanation and do not limit the order of the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0041] In one embodiment of the present invention, an integrated fast tunable narrow linewidth laser array light source based on AWG and single microring time-division multiplexing is provided, such as... Figure 1 As shown, it includes an 8-channel tunable DFB laser array (LASERS), a drive control circuit, an 8×1AWG, photonic wire bonding (PWB), a single micro-ring external cavity (MMR), and an output optical path (OUTPUT).

[0042] At any given time, the drive control circuit only puts the laser corresponding to the target wavelength into the AWG, while the other lasers remain switched off. The laser output from the currently operating channel is multiplexed by the Y-multiplexer and AWG to the common bus waveguide, and then coupled into the external cavity of a single microring.

[0043] When the current channel laser wavelength matches the microring resonant wavelength, the laser forms a resonant enhanced optical field within the microring. After the current time slot ends, the current channel is closed and switched to the next channel, repeating the above process to achieve arbitrarily fast tunable narrow linewidth output from 8 lasers within the target wavelength range.

[0044] The structure and fabrication process of the fast tunable narrow linewidth laser array source chip system with micro-ring external cavity of this embodiment will be further described below with reference to the accompanying drawings.

[0045] (I) Design and fabrication of multi-channel laser array chips

[0046] In this embodiment, the multi-channel laser array chip is used to provide an initial light source that meets the requirements of multi-channel and fast tunable operation. Its design focuses on ensuring the controllability of the output wavelength of each channel, the stability of the output power, the ability to switch wavelengths quickly, and the adjustment accuracy when matching with external cavity devices.

[0047] In terms of structural design, an array light source is constructed using multiple independent laser units, with each channel's output covering the target optical communication operating band. The array comprises an eight-channel tunable DFB laser array, with center wavelengths of 1547.6nm, 1548.4nm, 1549.2nm, 1550.0nm, 1550.8nm, 1551.6nm, 1552.4nm, and 1553.2nm, respectively, and adjacent channels spaced 0.8nm apart. The output power of a single laser is preferably controlled within the range of 10mW-20mW to balance the optical power level required for subsequent microring resonance enhancement with the requirements for on-chip waveguide transmission loss and thermal effect control. To improve the system's matching capability, the wavelength adjustment accuracy of a single laser is preferably 0.01nm, ensuring that wavelength mismatch is controlled within 0.05nm when coupled to the silicon-based microring external cavity, thereby reducing the impact of non-target frequency components on frequency selection and locking effects.

[0048] In terms of fabrication process, the laser array chip can be realized using InP-based semiconductor technology. Optimization of the active region quantum well structure improves laser emission efficiency and output stability. A Y-multiplexer and a TEC temperature control unit are integrated into the laser for fine adjustment of the laser center wavelength, thereby improving the overall matching capability of the multi-channel system and providing a stable initial light source foundation for narrow linewidth output.

[0049] (II) Design and fabrication of silicon-based photonic chips

[0050] In this invention, such as Figure 2 and Figure 3 As shown, the single micro-ring external cavity in the silicon-based photonic chip is the core device for achieving multi-target wavelength sharing and linewidth narrowing. Its design concept differs from the parallel structure where each laser corresponds to a micro-ring. Instead, it uses a single high-Q silicon-based micro-ring resonator coupled with a common bus waveguide and combined with an AWG to achieve multi-channel multiplexing, thereby realizing time-division multiplexing sharing of multiple laser channels by a single micro-ring.

[0051] In terms of structural design, the silicon-based photonic chip includes an 8×1 AWG, a common bus waveguide, and a single silicon-based microring external cavity. The eight lasers, after being Y-multiplexed, first enter the input ports of the AWG, are multiplexed by the AWG, and then converge into the common bus waveguide, where they are coupled with the evanescent field of the single microring resonator. This microring resonator is designed with its free spectral range (FSR) equal to or nearly equal to the laser array channel spacing, allowing each microring to form a periodic resonant spectrum matching the array wavelength grid within the operating wavelength band. The waveguide width is uniformly 500 nm, and the thickness is 220 nm. At a wavelength of 1550 nm, the effective refractive index of the waveguide is set to 2.5, the group refractive index to 4.0, and the quality factor (Q value) of all microrings is greater than 10. 5 When the target FSR is designed to be about 0.8 nm, the radius of the single microring is preferably about 120 μm.

[0052] In terms of circuit control, the fast switching circuit includes a laser driver gating module, a temperature control module, a timing control module, and a parameter storage module. The laser driver gating module implements electrical time-division multiplexing control of the 8-channel laser array, ensuring that only the currently active channel is active at any given time, while the other channels remain off or in low-bias standby mode. Simultaneously, the TEC temperature control module controls the laser temperature to ensure stable operation. The parameter storage module pre-stores control parameters, and the timing control module calls the corresponding parameters in a preset order to complete channel gating and stable output control, thereby achieving fast switching of the 8 laser channels and narrow linewidth output.

[0053] In terms of fabrication process, a 4-inch SOI silicon-on-insulator wafer is used as the substrate material. The top silicon layer of the SOI wafer has a thickness of 220 nm, and the buried oxide layer has a thickness of 3 μm. First, the microring and waveguide structure are patterned using deep ultraviolet lithography, with the lithography accuracy controlled within ±5 nm. Subsequently, the top silicon layer is etched using inductively coupled plasma etching (ICP-C) to a depth of 220 nm, with the sidewall perpendicularity deviation controlled within 1° to ensure high flatness of the waveguide sidewalls and reduce optical transmission loss. After completing the fabrication of the microring and waveguide structure, a 100 nm thick SiO2 thin film is deposited as a passivation layer using plasma-enhanced chemical vapor deposition (PECVD) to reduce the impact of environmental changes on the waveguide refractive index and improve the long-term stability of the device.

[0054] (III) Heterogeneous integration of lasers and silicon photonic chips

[0055] To achieve efficient optical coupling between InP-based laser array chips and silicon-based photonic chips, and to reduce mode mismatch caused by differences in material systems, this invention adopts a heterogeneous integration connection method based on grating couplers to optically interface the laser array chip with a silicon-based photonic chip that integrates an AWG and a micro-ring external cavity.

[0056] In specific implementation, a coupling grating is formed on the output waveguide end face of the InP laser using electron beam lithography. The grating has a period of 320 nm, a duty cycle of 0.5, an etching depth of 80 nm, and forms an 8° angle with the waveguide axis. On the input side of the silicon-based photonic chip, a matching coupling grating is fabricated at the front end of the AWG input waveguide using deep ultraviolet lithography. The matching grating has a period of 350 nm, an etching depth of 110 nm, and also forms an 8° angle with the waveguide axis. The optical signals output from the laser array undergo Y-combining and are then injected into the silicon-based photonic chip through the above heterogeneous coupling structure. They first enter the corresponding input ports of the AWG, then the AWG performs wavelength multiplexing and merges them into a common waveguide, and subsequently transmits them to the bus waveguide region where the subsequent single micro-ring external cavity is located.

[0057] To further reduce coupling loss between InP and the silicon-based photonic chip caused by abrupt changes in refractive index, a SiO2 buffer layer, a Si3N4 graded-layer layer, and an Al2O3 anti-reflection film are sequentially placed between the InP-side coupling grating and the silicon-based coupling grating. This reduces interface reflection, improves mode field transition, and enhances mode matching efficiency from the InP laser output to the silicon-based AWG input waveguide. With this structure, a continuous heterogeneous integrated transmission link is formed between the laser array, Y-multiplexer, AWG, common waveguide, and single microring external cavity. This allows the forward working light to enter the microring coupling region after routing through the AWG, thus constituting a complete heterogeneous integrated optical path.

[0058] The InP laser chip, AWG chip, and silicon-based microring chip are mounted together on a high thermal conductivity ceramic substrate. A six-axis precision alignment platform is used to adjust the relative positions of each chip, ensuring that the deviation of the coupling grating center in the X / Y directions is controlled within 0.5μm and the spacing in the Z direction is maintained at 5μm. During the alignment process, the coupling efficiency is monitored in real time using an infrared camera. When the coupling efficiency reaches 70% or more, the chip is fixed with low-temperature curing epoxy resin with a curing temperature below 80℃. After fixing, the entire device is encapsulated in a metal shell with a TEC temperature control module to reduce the impact of thermal expansion differences and control the coupling loss fluctuation under temperature cycling conditions to within 0.3dB, thereby achieving a highly reliable connection between the multi-channel laser array chip, AWG, and silicon-based microring outer cavity.

[0059] To better demonstrate the fast tunable narrow linewidth laser array source chip system based on the micro-ring external cavity structure in this embodiment, in a preferred embodiment, an eight-channel laser array chip is used as the initial source, and a silicon-based micro-ring external cavity is connected through an AWG to realize multi-channel, narrow linewidth laser output of different wavelengths, which meets the needs of multi-wavelength high coherence light sources in scenarios such as optical communication wavelength division multiplexing and multi-parameter sensing.

[0060] Step 1: In this embodiment, the initial light source uses an 8-channel tunable DFB laser array chip, with the center wavelength of each channel ( The wavelengths of the lasers were set to 1547.6nm, 1548.4nm, 1549.2nm, 1550.0nm, 1550.8nm, 1551.6nm, 1552.4nm, and 1553.2nm, respectively, with an interval of 0.8nm between adjacent channels. The output power of each laser was controlled within the range of 10mW-20mW to meet the power requirements of subsequent on-chip waveguide transmission, microring resonant enhancement, and feedback locking.

[0061] Step two: The AWG and the single microring external cavity are integrated on the same silicon-based photonic chip. The silicon-based chip uses an SOI process platform with a top silicon thickness of 220nm, a buried oxide layer thickness of 3μm, and an on-chip waveguide width of 500nm. The AWG adopts an 8×1 structure, with each input terminal corresponding to 8 laser inputs, and the common terminal connected to a bus waveguide, which is further coupled to the single microring external cavity.

[0062] The single microring external cavity is constructed using a single silicon-based microring resonator, with a designed center wavelength of 1550.4 nm, an effective refractive index of 2.5, and a group refractive index of 4.0. Based on the relationship between the free spectral range and the microring radius, the microring radius is set to approximately 120 μm, ensuring its FSR is close to 0.8 nm, thus matching the channel spacing of the laser array. The single microring quality factor Q is set to be greater than 10. 5Each laser beam enters a single microring via an optical coupler, where it resonates within the microring.

[0063] Step three: After the system enters the working state, the controller first selects the first laser, causing it to output the target wavelength light, which then enters the corresponding input terminal of the AWG via the Y-multiplexer. After being multiplexed by the AWG, this light enters the common bus waveguide from the AWG common terminal and then propagates to the single micro-ring external cavity coupling region.

[0064] The wavelength variation of the output laser was monitored using a high-resolution spectrometer (e.g., resolution <0.01nm), and the wavelength range in which a stable narrow-linewidth laser could be output was recorded to verify the compressibility of a narrow linewidth within the C-band. The output characteristic curve of the micro-ring external cavity in this embodiment is shown below. Figure 4 As shown.

[0065] This embodiment uses a micro-ring-based eight-channel fast tunable narrow-linewidth laser array source chip to poll and illuminate the output spectrum, such as... Figure 5 As shown.

[0066] For a single microring device itself, a broadband light source can be input into it to measure its transmission spectrum, thereby obtaining the position of the resonance peak, the full width at half maximum (FWHM), and the spacing between adjacent resonance peaks; then, based on the FWHM of the resonance peak... and resonant wavelength Calculate the microring quality factor The FSR was verified to be consistent with the design value based on the interval between adjacent resonance peaks, thus confirming that the single microring does indeed have a periodic resonance spectrum that matches the channel spacing of the 8 lasers.

[0067] Test results show that the feedback structure combining an AWG with a single microring external cavity used in this embodiment can achieve sequential frequency selection and narrow linewidth output of a multi-channel laser based on a single high-Q microring. Compared with the initial system without microring external cavity feedback, the system output linewidth is significantly reduced, and the laser frequency stability and coherence are significantly improved. At the same time, since the microring FSR is pre-matched with the array channel spacing, power consumption and control complexity are effectively reduced.

[0068] Furthermore, in this embodiment, the AWG, the common bus waveguide, and the single micro-ring external cavity are all built on the same silicon-based photonic chip, which facilitates connection with the InP laser array using a heterogeneous integration method, thereby taking into account the miniaturization, integration, and multi-channel expansion capabilities of the system.

[0069] For those skilled in the art, without departing from the basic concept of this invention, further adjustments can be made to the number of laser channels, the number of AWG channels, the micro-ring coupling structure, the feedback ratio, etc., and all such changes should fall within the protection scope of this invention.

Claims

1. A fast-tunable narrow-linewidth laser array light source based on AWG and single micro-ring time-division multiplexing, characterized in that, include: Laser array, drive control circuit, arrayed waveguide grating, common bus waveguide, single micro-ring external cavity and output optical path; The laser array includes N tunable lasers, the output of each laser being connected to the input of the array waveguide grating, for providing laser output of any target wavelength within the target wavelength range; The common end of the arrayed waveguide grating is connected to a common bus waveguide, and the common bus waveguide is coupled to a single micro-ring external cavity; The drive control circuit is used to control the enable state of the current working channel in the laser array in a time-division multiplexing manner, so that only one laser outputs the target wavelength at any given time, thereby achieving rapid and stable wavelength switching. The laser from the currently selected working channel is multiplexed by the arrayed waveguide grating and enters the common bus waveguide, where it resonates and couples with the outer cavity of the micro-ring. When the resonant wavelength of the micro-ring outer cavity matches the laser wavelength of the current working channel, the micro-ring outer cavity performs frequency selectivity on the input laser, narrowing the laser linewidth.

2. The integrated fast tunable narrow linewidth laser array light source according to claim 1, characterized in that, The laser array is an 8-channel tunable DFB laser array, with the center wavelengths of each channel arranged at preset intervals, and it integrates a Y-multiplexer and a TEC temperature control unit.

3. The integrated fast tunable narrow linewidth laser array light source according to claim 1, characterized in that, The arrayed waveguide grating is an 8×1 or 1×8 bidirectional multiplexing or demultiplexing device used to multiplex the laser of the current working channel to a common bus.

4. The integrated fast tunable narrow linewidth laser array light source according to claim 1, characterized in that, The microring resonant wavelength λ res satisfy: ； In the formula, It is the effective refractive index of the waveguide. It is the radius of the micro-ring. It is an integer, representing the order of the resonant mode; When the laser wavelength output by the laser array chip is similar to λ res During matching, the phase superposition of light propagating in each ring within the micro-ring enhances, forming a resonant light field.

5. The integrated fast tunable narrow linewidth laser array light source according to claim 4, characterized in that, The free spectral range of the outer cavity of the microring Designed to be equal to or nearly equal to the channel spacing of the laser array, with a free spectral range. Defined as the wavelength interval between two adjacent resonant peaks, the formula is as follows: ； in, It is the resonant wavelength. The group refractive index.

6. The integrated fast tunable narrow linewidth laser array light source according to claim 1, characterized in that, The drive control circuit uses logic gates to implement time slot selection, so that only one laser can output a beam at any given time, thereby enabling the laser array to switch rapidly within the target wavelength range.

7. The integrated fast tunable narrow linewidth laser array light source according to claim 1, characterized in that, The output optical path is connected to the transmission end of the common bus waveguide and / or the output end of the micro-ring outer cavity, and is used to output the narrow linewidth laser corresponding to the current time slot.

8. The integrated fast tunable narrow linewidth laser array light source according to claim 1, characterized in that, The outer cavity of the microring is a silicon-based microring outer cavity, manufactured based on silicon-based semiconductor technology.

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