Reflection suppression structure, silicon optical chip and optical module
By arranging a beam splitter at the incident end of the reflection point of the silicon photonic chip, the optical signal is divided into two beams and their phase difference is controlled to achieve interference cancellation, thus solving the problem of on-chip reflection of silicon photonic chips and improving the stability and reliability of the communication system.
Patent Information
- Application Number
- CN202511996056.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-02-10
AI Technical Summary
Existing technologies cannot effectively suppress on-chip reflections in silicon photonic chips, which affects the stability and reliability of communication systems.
A beam splitter is placed at the incident end of the reflection point to split the input optical signal into two optical signals. By controlling their phase difference, the reflected light is completely or partially canceled out at the main input port to achieve reflection suppression.
It effectively suppresses on-chip reflections, improves the stability and reliability of communication systems, has a simple structure, is compatible with conventional chip manufacturing processes, and occupies a small area.
Smart Images
Figure CN121500510A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of silicon-based photonics integration technology, specifically relating to a reflection suppression structure, a silicon photonic chip, and an optical module. Background Technology
[0002] Silicon-based optoelectronics technology utilizes mature CMOS processes to achieve monolithic integration of optoelectronic devices on a silicon-on-insulator (SOI) platform, and has become the mainstream solution for achieving high-speed, high-density, and low-cost optical interconnects. However, due to the significant refractive index difference between the silicon material and the cladding, as well as the complex mode transitions within the chip, numerous reflective interfaces and mode mismatch regions exist within the chip, causing on-chip reflections. These reflections severely interfere with the main signal at the receiver, producing ghosting and eye diagram jitter, degrading the bit error rate, and significantly impacting the stability and reliability of the communication system.
[0003] Current methods for suppressing reflection in silicon photonics chips primarily involve adding waveguide end-face coatings, tilting waveguide end-faces, adding optical circulators or isolators, and optimizing fab processes to reduce process node size. However, adding waveguide end-face coatings introduces additional losses and process complexity, and fails to effectively suppress on-chip reflection. Tilting waveguide end-faces offers limited reflection reduction benefits and increases process complexity, also failing to solve on-chip reflection issues. Adding optical circulators or isolators is incompatible with the chip, resulting in large device sizes, high additional losses, and increased material costs. Optimizing fab processes significantly increases fabrication costs, and the new processes cannot guarantee yield. Summary of the Invention
[0004] The purpose of this application is to provide a reflection suppression structure, a silicon photonics chip, and an optical module to solve the technical problem that the existing technology cannot effectively suppress on-chip reflection of silicon photonics chips. On-chip reflection will interfere with the main signal of the receiver, degrade the bit error rate, and significantly affect the stability and reliability of the communication system.
[0005] To achieve the above objectives, the first aspect of this application provides a reflection suppression structure, comprising:
[0006] An input waveguide is arranged on the incident end side of the reflection point, and the input waveguide is used to transmit optical signals to the reflection point;
[0007] A beam splitter is arranged between the reflection point and the input waveguide. The beam splitter has a main input port, a bypass input port, a first output port and a second output port. The main input port is connected to the input waveguide, and the first output port and the second output port are respectively connected to the reflection point.
[0008] The beam splitter is used to split the optical signal of the input waveguide into a first optical signal and a second optical signal and input them into the reflection point respectively; to split the first reflected light of the reflection point in response to the first optical signal into two beams and output them from the main input port and the side input port respectively; and to split the second reflected light of the reflection point in response to the second optical signal into two beams and output them from the main input port and the side input port respectively.
[0009] The phase difference between the first optical signal and the second optical signal is 76.5~103.5°, so that the output component of the first reflected light at the main input port and the output component of the second emitted light at the main input port completely or partially interfere with each other to suppress the reflected light output through the main input port.
[0010] In one or more embodiments, the optical power of the first optical signal and the second optical signal are equal and the phase difference is 90°, so that the output component of the first reflected light at the main input port and the output component of the second emitted light at the main input port completely interfere with each other.
[0011] In one or more embodiments, the beam splitter is a multimode interference coupler or a directional coupler.
[0012] To achieve the above objectives, a second aspect of this application provides a silicon photonics chip, which includes the reflection suppression structure described in any of the above embodiments, wherein a reflection structure is formed on the silicon photonics chip, and the reflection point is arranged at the incident end of the reflection structure.
[0013] In one or more embodiments, a beam combiner is further included, which is arranged at the output end of the reflective structure and is used to couple the first optical signal and the second optical signal that have passed through the reflective structure and then output them.
[0014] In one or more embodiments, the beam combiner is a multimode interference coupler or a directional coupler.
[0015] In one or more embodiments, the reflection structure includes a transition module, the transition module including a first transition structure and a second transition structure connected in parallel, the reflection point being arranged at the incident end of the first transition structure and the incident end of the second transition structure, and the first output port and the second output port being connected to the first transition structure and the second transition structure, respectively.
[0016] In one or more embodiments, it further includes:
[0017] An optical fiber chip coupler is connected to the input end of the input waveguide, and the optical fiber chip coupler is used to introduce optical signals into the silicon photonic chip;
[0018] A functional module is connected to the output terminal of the transition module. The functional module is used to receive the optical signal output by the transition module and perform optical signal processing.
[0019] In one or more embodiments, a functional module is further included, which is connected to the input end of the input waveguide and is used to process optical signals and output the processed optical signals via the input waveguide.
[0020] In one or more embodiments, the fiber optic chip coupler is an edge coupler.
[0021] In one or more embodiments, the functional module is a Mach-Zehnder modulator.
[0022] In one or more embodiments, the input waveguide is a silicon nitride waveguide or a silicon waveguide.
[0023] To achieve the above objectives, a third aspect of this application provides an optical module including the silicon photonics chip described in any of the above embodiments.
[0024] The advantages of this application, which differ from existing technologies, are:
[0025] This application's reflection suppression structure arranges a beam splitter between the incident end of the reflection point and the input waveguide. The beam splitter can split the input light into a first optical signal and a second optical signal, which are output to the reflection point respectively. The reflected light from the first and second optical signals at the main input port of the beam splitter completely or partially interferes with each other, thus achieving reflection suppression on the main optical path by utilizing the mutual interference between the reflected light. The structure is simple, fully compatible with the process flow of conventional chips, occupies a very small area when applied to a chip, can effectively suppress on-chip reflections, and has strong applicability.
[0026] The silicon photonics chip of this application can significantly suppress on-chip reflection by arranging a reflection suppression structure at the incident end of the reflection point, thereby improving the stability and reliability of the communication system.
[0027] Compared to conventional silicon photonics chips, the silicon photonics chip of this application does not require the introduction of heterogeneous materials to achieve on-chip reflection suppression, is fully compatible with the process flow of conventional chips, and has a very small chip footprint and strong applicability. Attached Figure Description
[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] Figure 1 This is a schematic diagram of one embodiment of the reflection suppression structure of this application;
[0030] Figure 2 This is a schematic diagram illustrating the working principle of the beam splitter in this application;
[0031] Figure 3 This is a graph showing the corresponding data of the splitting ratio and extinction ratio of the spectrometer in this application;
[0032] Figure 4 This is a graph showing the corresponding data of phase error and extinction ratio of the beam splitter in this application;
[0033] Figure 5 This is a schematic diagram of the structure of one embodiment of the silicon photonics chip of this application;
[0034] Figure 6 This is a schematic diagram of another embodiment of the silicon photonics chip of this application;
[0035] Figure 7 This is a schematic diagram of another embodiment of the silicon photonics chip in this application.
[0036] Explanation of key figure labels:
[0037] Input waveguide 100;
[0038] 200; main input port 201; bypass input port 202; first output port 203; second output port 204;
[0039] Transition module 300; First transition structure 301; Second transition structure 302;
[0040] Fiber optic chip coupler 400;
[0041] Functional modules 500;
[0042] Optical combiner 600;
[0043] First optical signal a1; second optical signal a2; first reflected light b1; second reflected light b2. Detailed Implementation
[0044] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.
[0045] Silicon photonics chips contain numerous reflective interfaces and mode mismatch regions, leading to on-chip reflection problems. The reflected light can severely interfere with the main signal at the receiver, causing ghosting and eye diagram jitter, which degrades the bit error rate and significantly affects the stability and reliability of the communication system.
[0046] Existing reflection suppression methods cannot effectively suppress on-chip reflections. To address this, the applicant has developed a reflection suppression structure that utilizes the destructive interference between reflected light to suppress reflections on the main optical path. This structure is simple, fully compatible with conventional chip manufacturing processes, and can be applied to silicon photonic chips to effectively suppress on-chip reflections.
[0047] Specifically, please refer to Figure 1 , Figure 1 This is a schematic diagram of one embodiment of the reflection suppression structure of this application.
[0048] like Figure 1 As shown, the reflection suppression structure includes an input waveguide 100 arranged on the incident end side of the reflection point A, which is used to transmit optical signals to the reflection point A.
[0049] The reflection suppression structure also includes a beam splitter 200 arranged between the reflection point A and the input waveguide 100. The beam splitter 200 has a main input port 201, a bypass input port 202, a first output port 203, and a second output port 204. The main input port 201 is connected to the input waveguide 100, and the first output port 203 and the second output port 204 are respectively connected to the reflection point A.
[0050] The optical signal input through the input waveguide 100 can be split into a first optical signal a1 and a second optical signal a2 by the beam splitter 200 and input to the reflection point A respectively.
[0051] The first reflected light b1 of the first optical signal a1 at reflection point A can return to the beam splitter 200 through the first output port 203; correspondingly, the second reflected light b2 of the second optical signal a2 at reflection point A can return to the beam splitter 200 through the second output port 204.
[0052] The beam splitter 200 can split the first reflected light b1 into two beams and output them from the main input port 201 and the bypass input port 202 respectively, and at the same time, it can split the second reflected light b2 into two beams and output them from the main input port 201 and the bypass input port 202 respectively.
[0053] The phase difference between the first optical signal a1 and the second optical signal a2 is 76.5~103.5°, which enables the output component of the first reflected light b1 at the main input port 201 to completely or partially interfere with and cancel out the output component of the second reflected light b2 at the main input port 201, thereby suppressing the reflected light output through the main input port 201 and achieving the purpose of reflection suppression on the main optical path.
[0054] The working principle of the beam splitter 200 of this application is described in detail below. Since the beam splitter 200 does not involve changes in the polarization mode of light, the principle is introduced using TE light under ideal conditions as an example.
[0055] Please see Figure 2 , Figure 2 This is a schematic diagram illustrating the working principle of the beam splitter in this application. Figure 2 As shown, a beam of TE light enters the beam splitter 200 through the main input port 201 (IN1), and its normalized Jones matrix is: ,in, This represents the electric field strength of the input light.
[0056] The Jones matrix of the first output port 203 (Bar port) and the second output port (Cross port) of the beam splitter 200 relative to the main input port 201 is as follows:
[0057] ;
[0058] In the formula, The Jones matrix for beam splitter 200. The electric field strength at the first output port 203 is... The electric field strength at the second output port 204 is given by i, where i is the imaginary unit.
[0059] After transmission, the first optical signal a1 and the second optical signal a2 output from the first output port 203 and the second output port 204 are respectively:
[0060] ;
[0061] ;
[0062] The physical meaning of the above formula is: the TE light input from the main input port 201 (IN1) is split by 3dB into two ports, the first output port 203 (Bar end) and the second output port 204 (Cross end), after passing through the beam splitter 200. The phase of the first optical signal a1 of the first output port 203 is 0, and the phase of the second optical signal a2 of the second output port 204 is 90° ahead. The polarization state does not change, and the optical power of the two is the same.
[0063] The first optical signal a1 and the second optical signal a2 are respectively input to the reflection point A and are reflected at the reflection point A. The first reflected light b1 and the second reflected light b2 are transmitted in reverse from the reflection point A and return to the beam splitter 200 through the first output port 203 (Bar end) and the second output port 204 (Cross end).
[0064] Within the beam splitter 200, the first reflected light b1 is split into two beams, which are output from the main input port 201 (IN1) and the bypass input port 202 (IN2), respectively. The two beams are:
[0065] ;
[0066] ;
[0067] Within the beam splitter 200, the second reflected light b2 is split into two beams, which are output from the main input port 201 (IN1) and the bypass input port 202 (IN2), respectively. The two beams are:
[0068] ;
[0069] ;
[0070] In the above formulas, R is the reflection coefficient at the reflection point. The Jones matrix from the output port of beam splitter 200 to the reflection point waveguide only introduces a fixed phase difference. .
[0071] From the above formula, it can be seen that the main input port 201's and The phase difference is 180°, and the optical power is the same, so the two can completely interfere and cancel each other out; the bypass input port 202 and With a phase difference of 0°, the interference is constructive, thus realizing the function of guiding the on-chip reflected light from the main input port 201 (IN1) to the bypass input port 202 (IN2), greatly reducing the unavoidable reflection accumulation of reflection points inside the chip.
[0072] The above analysis is based on TE polarized light under ideal conditions. The analysis process for TM polarized light is the same and will not be repeated here. Light in other polarization states can be decomposed into a combination of TE and TM, thus all of which can achieve reflection suppression.
[0073] In an ideal state, the optical power of the first optical signal a1 and the second optical signal a2 are equal and the phase difference is 90°. However, in a non-ideal state, the splitting ratio of the beam splitter 200 for light with different polarization states may not be consistent. At the same time, due to the influence of different polarization and process errors, there may be a deviation between the first optical signal a1 and the second optical signal a2 and 90°.
[0074] Furthermore, to verify the reflection suppression effect of this application under non-ideal conditions, the applicant introduced the extinction ratio to describe the reflection suppression performance of the beam splitter 200. The formula for calculating the extinction ratio is as follows: Where P1 is the main path reflected light power without the beam splitter 200, and P2 is the main path reflected light power after the beam splitter 200 is installed.
[0075] The applicant tested the extinction ratio ER corresponding to the spectrometer 200 of the IMB with different splitting ratios and obtained the following results. Figure 3 , Figure 3 This is a graph showing the corresponding data of the splitting ratio and extinction ratio of the beam splitter in this application. For example... Figure 3 As shown, when the splitting ratio IMB is close to 0 dB, the beam splitter 200 can basically suppress all reflected light. Even if the splitting ratio IMB deteriorates to more than 6 dB, the extinction ratio of the main input port 201IN1 of the beam splitter 200 is still more than 10 dB, that is, it has a reflection gain of more than 10 dB, which can significantly suppress on-chip reflection.
[0076] Furthermore, the applicant tested the effect of phase error on the extinction ratio of the main input port 201 of the beam splitter 200, assuming the phase difference between the first optical signal a1 and the second optical signal a2 is... Then, when the reflected light is combined at the main input port 201IN1, at least [amount] has accumulated. For phase error, please refer to Figure 4 , Figure 4 This is a graph showing the phase error and extinction ratio of the beam splitter in this application.
[0077] like Figure 4 As shown, when the phase error When the phase error is close to 0, the beam splitter 200 can basically suppress all reflected light; even with phase error At 13.5°, the main input of the beam splitter 200 still has a gain of 10dB, that is, a reflection gain of more than 10dB, which can significantly suppress reflected light in the main optical path.
[0078] In one embodiment, the beam splitter 200 can be specifically a multimode interference coupler (MMI). The MMI can achieve broadband 3dB beam splitting, and the phase difference at the output port is 90°, which meets the requirements of this embodiment.
[0079] In another embodiment, the beam splitter 200 can also be a directional coupler, that is, a 3dB directional coupler can also achieve the effect of this embodiment at the corresponding wavelength, but since the 3dB directional coupler has strong wavelength dependence, it is difficult to achieve broadband reflection suppression.
[0080] In other embodiments, the beam splitter 200 can also be other devices that can achieve the same function, and all can achieve the effect of this embodiment.
[0081] In summary, the reflection suppression structure of this embodiment utilizes the destructive interference of two reflected beams to significantly suppress reflected light on the main optical path. It has a simple structure, is fully compatible with conventional chip manufacturing processes, occupies a very small area when applied to a chip, effectively suppresses on-chip reflections, and has strong applicability.
[0082] Furthermore, the applicant also provides a silicon photonic chip including any of the above-described reflection suppression structures; please refer to [link to relevant documentation]. Figure 5 , Figure 5 This is a schematic diagram of one embodiment of the silicon photonics chip of this application.
[0083] like Figure 5 As shown, a reflective structure is formed on the silicon photonic chip, and a reflection suppression structure is arranged at the incident end of the reflective structure to effectively suppress on-chip reflection of the input light by the reflective structure.
[0084] Specifically, in this embodiment, the reflection structure is a transition module 300. The transition module 300 includes a first transition structure 301 and a second transition structure 302 connected in parallel. The input waveguide 100 is used to transmit optical signals to the transition module 300. The first output port 203 and the second output port 204 are respectively connected to the first transition structure 301 and the second transition structure 302.
[0085] The first transition structure 301 can cause the first reflected light b1 of the first optical signal a1 and the second reflected light b2 of the second transition structure 302 to interfere with all or part of the output components of the main input port 201, thereby achieving the purpose of suppressing on-chip reflection.
[0086] In silicon photonics chips, transition structures are used to transmit optical signals between waveguides of different materials, layers, and types. Due to the large refractive index mismatch and mode mismatch during material conversion, the input end of the transition structure will cause significant on-chip reflection. In this embodiment, by setting a reflection suppression structure at the input end of the transition structure, the purpose of effectively suppressing on-chip reflection can be achieved.
[0087] It should be noted that this embodiment only uses the reflection structure as an example of the transition module 300; in other embodiments, the reflection structure can also be any structure with on-chip reflection on the silicon photonics chip, and the reflection point can also be any on-chip reflection point on the silicon photonics chip. By setting a reflection suppression structure at the incident end of the reflection point, the purpose of effectively suppressing on-chip reflection can be achieved.
[0088] The silicon photonics chip based on this embodiment can significantly suppress on-chip reflections and improve the stability and reliability of communication systems. In addition, compared with conventional silicon photonics chips, it does not require the introduction of heterogeneous materials, is fully compatible with the process flow of conventional chips, and has a very small chip footprint, making it highly widely applicable.
[0089] The structure of the silicon photonics chip in this application will be described below, such as... Figure 5 As shown, in this embodiment, the silicon photonics chip also includes an optical fiber chip coupler 400 and a functional module 500.
[0090] The fiber optic chip coupler 400 is connected to the input end of the input waveguide 100 and is used to introduce optical signals into the silicon photonic chip; the functional module 500 is connected to the output end of the transition module 300 and is used to receive the optical signals output by the transition module 300 and perform optical signal processing.
[0091] Based on this structure, the input waveguide 100 can be specifically a silicon nitride waveguide, which is arranged on the silicon nitride layer to guide the optical signal input from the optical fiber to the transition module 300 located between the silicon nitride and silicon layers. The beam splitter 200 is arranged at the input end of the transition module 300 to suppress on-chip reflections caused by large refractive index mismatch and mode mismatch.
[0092] In one embodiment, the fiber optic chip coupler 400 can be specifically an edge coupler, where light entering the silicon photonic chip from the edge coupler undergoes a large refractive index and mode abrupt change when passing through the transition module 300, which is the main reflection point. Placing a beam splitter 200 in front of this reflection point can suppress on-chip reflection to the maximum extent.
[0093] Of course, in other embodiments, the fiber optic chip coupler 400 can also be a grating coupler, or in other embodiments, the reflection suppression structure can also be arranged at the incident end of any other on-chip reflection point, all of which can achieve the purpose of suppressing on-chip reflection and to a certain extent achieve the effect of this embodiment.
[0094] In one implementation, functional module 500 may be specifically a Mach-Zehnder modulator to perform signal modulation.
[0095] In other embodiments, the functional module 500 can also be any type of functional module 500 commonly used in silicon photonics chips, all of which can achieve the effects of this embodiment.
[0096] In the above embodiments, the optical signal passing through the first transition structure 301 and the second transition structure 302 directly enters the functional module 500 for processing; in another embodiment, please refer to... Figure 6 , Figure 6 This is a schematic diagram of another embodiment of the silicon photonics chip of this application.
[0097] like Figure 6As shown, in this embodiment, the output end of the transition module 300 is also provided with a light combiner 600. The light combiner 600 couples the optical signal output by the first transition structure 301 and the optical signal output by the second transition structure 302 and outputs them to the functional module 500, thereby optimizing the processing effect of the functional module 500 and simplifying the hardware.
[0098] In one embodiment, the beam combiner 600 can be a multimode interference coupler (MMI); in other embodiments, the beam combiner 600 can also be other devices that can achieve beam combining function, such as directional couplers, etc., which can be selected based on actual needs, and all can achieve the effect of this embodiment.
[0099] Furthermore, this embodiment only uses the reflective structure as an example of the transition module 300. In other embodiments, when the reflective structure is another structure on the silicon photonic chip with on-chip reflective points, the beam combiner 600 can also be arranged at the output end of other reflective structures, and the effect of this embodiment can also be achieved.
[0100] In the above embodiments, the beam splitter 200 is arranged on the input side of the functional module 500 to suppress on-chip reflections at the front end of the functional module 500. In another embodiment, the beam splitter 200 may also be arranged on the output side of the functional module 500 to suppress on-chip reflections at the rear end of the functional module 500.
[0101] Please see Figure 7 , Figure 7 This is a schematic diagram of another embodiment of the silicon photonics chip described in this application. Figure 6 As shown, in this embodiment, the functional module 500 of the silicon photonics chip is connected to the input terminal of the input waveguide 100. The functional module 500 is used to process optical signals and output the processed optical signals through the input waveguide 100.
[0102] The beam splitter 200 is used to suppress the reflection of the optical signal processed by the functional module 500 at the input end of the transition module 300.
[0103] Specifically, in this embodiment, the input waveguide 100 can be a silicon waveguide, which is arranged on the silicon layer to guide the optical signal processed by the functional module 500 to the transition module 300 located between the silicon layer and the silicon nitride layer. The beam splitter 200 is arranged at the input end of the transition module 300 to suppress on-chip reflections caused by large refractive index mismatch and mode mismatch.
[0104] It should be noted that in the above embodiments, the silicon photonic chip is only equipped with a single beam splitter 200; in other embodiments, when the silicon photonic chip has multiple on-chip reflection points, a beam splitter 200 can be arranged in front of each on-chip reflection point or some on-chip reflection points to effectively suppress on-chip reflection, and the effect of this embodiment can be achieved.
[0105] This application also provides an optical module, which includes a silicon photonics chip according to any of the above embodiments.
[0106] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0107] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A reflection suppression structure, characterized in that, include: An input waveguide is arranged on the incident end side of the reflection point, and the input waveguide is used to transmit optical signals to the reflection point; A beam splitter is arranged between the reflection point and the input waveguide. The beam splitter has a main input port, a bypass input port, a first output port and a second output port. The main input port is connected to the input waveguide, and the first output port and the second output port are respectively connected to the reflection point. The beam splitter is used to split the optical signal of the input waveguide into a first optical signal and a second optical signal and input them into the reflection point respectively; to split the first reflected light of the reflection point in response to the first optical signal into two beams and output them from the main input port and the side input port respectively; and to split the second reflected light of the reflection point in response to the second optical signal into two beams and output them from the main input port and the side input port respectively. The phase difference between the first optical signal and the second optical signal is 76.5~103.5°, so that the output component of the first reflected light at the main input port and the output component of the second emitted light at the main input port completely or partially interfere with each other to suppress the reflected light output through the main input port.
2. The reflection suppression structure according to claim 1, characterized in that, The first optical signal and the second optical signal have equal optical power and a phase difference of 90°, so that the output component of the first reflected light at the main input port and the output component of the second emitted light at the main input port completely interfere with each other.
3. The reflection suppression structure according to claim 1, characterized in that, The beam splitter is a multimode interference coupler or a directional coupler.
4. A silicon photonics chip, characterized in that, The device includes the reflection suppression structure according to any one of claims 1 to 3, wherein a reflection structure is formed on the silicon photonic chip, and the reflection point is arranged at the incident end of the reflection structure.
5. The silicon photonic chip according to claim 4, characterized in that, It also includes a beam combiner, which is arranged at the output end of the reflective structure and is used to couple the first optical signal and the second optical signal that have passed through the reflective structure and then output them.
6. The silicon photonic chip according to claim 5, characterized in that, The optical combiner is a multimode interference coupler or a directional coupler.
7. The silicon photonics chip according to claim 4, characterized in that, The reflection structure includes a transition module, which includes a first transition structure and a second transition structure connected in parallel. The reflection point is arranged at the incident end of the first transition structure and the incident end of the second transition structure. The first output port and the second output port are respectively connected to the first transition structure and the second transition structure.
8. The silicon photonic chip according to claim 7, characterized in that, Also includes: An optical fiber chip coupler is connected to the input end of the input waveguide, and the optical fiber chip coupler is used to introduce optical signals into the silicon photonic chip; A functional module is connected to the output terminal of the transition module. The functional module is used to receive the optical signal output by the transition module and perform optical signal processing.
9. The silicon photonic chip according to claim 7, characterized in that, It also includes a functional module connected to the input end of the input waveguide. The functional module is used to process optical signals and output the processed optical signals via the input waveguide.
10. The silicon photonics chip according to claim 8, characterized in that, The fiber optic chip coupler is an edge coupler; and / or, The functional module is a Mach-Zehnder modulator.
11. The silicon photonic chip according to claim 4, characterized in that, The input waveguide is a silicon nitride waveguide or a silicon waveguide.
12. An optical module comprising the silicon photonic chip as described in any one of claims 4 to 11.