An on-chip hybrid filter combined with mzi and mrr and a control method thereof

Abstract

The present application relates to filter, specifically to a kind of on-chip hybrid filter of MZI and MRR joint and its control method, to solve the insufficient of the relatively limited function of single tunable filter in prior art, a kind of on-chip hybrid filter of MZI and MRR joint, including MZI structure and MRR filter module located at MZI upper arm and MZI lower arm respectively, the MRR filter module includes third beam splitter, fourth beam splitter, fifth beam splitter, sixth beam splitter, phase shifter is arranged between third beam splitter and fourth beam splitter, between fourth beam splitter and fifth beam splitter, between third beam splitter and fifth beam splitter, between fourth beam splitter and sixth beam splitter;While providing a kind of control method of the above-mentioned on-chip hybrid filter of MZI and MRR joint, so that it simultaneously outputs a group of frequency spectrum complementary optical signals and a group of frequency spectrum same optical signals.

Description

TECHNICAL FIELD

[0001] The present application relates to a filter, in particular to a mixed filter on a chip combining MZI and MRR and a control method thereof. BACKGROUND

[0002] The rapid growth of data traffic has driven the development of optical fiber communication, and under the assistance of high-performance silicon photonic chips with large bandwidth and low power consumption, optical interconnection networks use optical wavelength division multiplexing technology to provide a solution for optical fiber communication. With the popularity of optical wavelength division multiplexing technology, multi-channel filters have become a key component for efficient data transmission and improved network capacity. The main role of multi-channel filters is to select or separate different optical wavelength channels in an optical fiber communication system, allowing multiple signals to be transmitted in parallel in the same optical fiber.

[0003] As a kind of multi-channel filter, micro-ring resonator has unique advantages such as small structure, strong plasticity and easy adjustment, and has attracted widespread attention in the field of optical wavelength division multiplexing. The tuning technology of multi-channel filter based on micro-ring resonator is an important research direction in the field of optical communication and optical information processing. The design of an adjustable filter is also a major technical challenge in the field of multi-channel filters. The existing single adjustable filter has relatively limited functions, mainly focusing on the tunability of extinction ratio, center wavelength and free spectral range. Researchers are actively exploring the combination of micro-ring resonators with other structures to develop new types of adjustable filters to achieve more diversified functions. SUMMARY

[0004] The purpose of the present application is to solve the problem of the relatively limited functions of the single adjustable filter in the prior art, and to provide a mixed filter on a chip combining MZI and MRR and a control method thereof. The micro-ring resonator (MRR) is combined with the Mach-Zehnder interferometer (MZI) to realize an adjustable filter with a new structure and diversified functions.

[0005] To achieve the above-mentioned purpose, the technical solution provided by the present application is as follows:

[0006] The application discloses an on-chip hybrid filter combined with MZI and MRR, which comprises an MZI structure; the MZI structure comprises a first beam splitter, a second beam splitter, an MZI upper arm and an MZI lower arm; two input ends of the first beam splitter are used for being connected with external devices respectively, and two output ends of the first beam splitter are connected with one end of the MZI upper arm and the MZI lower arm respectively; two input ends of the second beam splitter are connected with the other end of the MZI upper arm and the MZI lower arm respectively, and two output ends of the second beam splitter are used for being connected with external devices respectively; the special part of the application is that the MRR filtering module is arranged on the MZI upper arm and the MZI lower arm respectively; the MRR filtering module comprises a third beam splitter, a fourth beam splitter, a fifth beam splitter and a sixth beam splitter; one input end of the third beam splitter is connected with one output end of the first beam splitter, and the other input end of the third beam splitter is connected with one input end of the fourth beam splitter and is provided with a phase shifter between the third beam splitter and the fourth beam splitter; the other input end of the fourth beam splitter is connected with one output end of the fifth beam splitter and is provided with a phase shifter between the fourth beam splitter and the fifth beam splitter; one output end of the third beam splitter is connected with one input end of the fifth beam splitter and is provided with a phase shifter between the third beam splitter and the fifth beam splitter, and the other output end of the third beam splitter is connected with the other input end of the fifth beam splitter; one output end of the fourth beam splitter is connected with one input end of the sixth beam splitter, and the other output end of the fourth beam splitter is connected with the other input end of the sixth beam splitter and is provided with a phase shifter between the fourth beam splitter and the sixth beam splitter; the other output end of the fifth beam splitter is connected with one output end of the sixth beam splitter; the other output end of the sixth beam splitter is connected with one input end of the second beam splitter; and the above-mentioned ports are connected through waveguides.

[0007] Further, a front side phase shifter is arranged between the output end of the first beam splitter and one input end of the third beam splitter of the MZI lower arm.

[0008] The MZI lower arm is provided with a rear side phase shifter between the other input end of the fourth beam splitter and the output end of the fifth beam splitter.

[0009] Further, the phase shifter, the front side phase shifter and the rear side phase shifter are all micro heaters.

[0010] Further, the first beam splitter and the second beam splitter are both multimode interferometers.

[0011] Further, the waveguide, the first beam splitter, the second beam splitter, the third beam splitter, the fourth beam splitter, the fifth beam splitter and the sixth beam splitter are all made of silicon, silicon oxide, silicon nitride, a three-five material or lithium niobate material.

[0012] The MZI structure and the MRR filtering module are made by using a CMOS process.

[0013] Meanwhile, the application also provides a control method of the above-mentioned on-chip hybrid filter combined with MZI and MRR, and the special part of the control method is that the control method comprises the following steps:

[0014] Step 1, input the initial optical signal into the first beam splitter, the first beam splitter divides the initial optical signal into two beams, forming an upper optical path and a lower optical path, which are transmitted to the MZI upper arm and the MZI lower arm respectively;

[0015] Step 2, the optical signal of the upper optical path is filtered by the MRR filtering module of the MZI upper arm, part of which is transmitted forward to the second beam splitter, and the rest is transmitted backward to the first beam splitter;

[0016] The optical signal of the lower optical path is filtered by the MRR filtering module of the MZI lower arm, part of which is transmitted forward to the second beam splitter, and the rest is transmitted backward to the first beam splitter;

[0017] The second beam splitter combines and divides the optical signals transmitted forward by the upper optical path and the lower optical path, obtaining two forward output optical signals; the first beam splitter combines and divides the optical signals transmitted backward by the upper optical path and the lower optical path, obtaining two backward output optical signals;

[0018] Step 3, adjust the power applied to the phase shifter and / or the front phase shifter and / or the rear phase shifter to realize phase modulation of the optical signal of the upper optical path and / or the lower optical path.

[0019] Further, step 3 is specifically:

[0020] The power applied to the phase shifter of the two MRR filtering modules corresponds to the same, and the power applied to the front phase shifter and / or the rear phase shifter is adjusted to modulate the phase of the optical signal of the lower optical path.

[0021] The beneficial effects of the present application are:

[0022] 1. The on-chip hybrid filter combined with MZI and MRR of the present application is a tunable multi-channel filter, which combines the structures of Mach-Zehnder interferometer and micro-ring resonator, and sets multiple phase shifters in the MRR filtering module. By adjusting the power applied to the phase shifter of the MRR filtering module, the optical signal is accurately phase modulated, so as to realize the tunable of extinction ratio, center wavelength and free spectral range; through the structure, four port outputs can be realized, a group of spectrum complementary optical signals and a group of spectrum same optical signals can be generated at the same time, the adjustment process is convenient and flexible, the quality and anti-interference ability of the output optical signal are effectively improved, and the system capacity is improved.

[0023] 2. The control method of the on-chip hybrid filter combined with MZI and MRR of the present application adjusts the phase shifter and / or the front phase shifter and / or the rear phase shifter of the MRR filtering module to modulate the phase of the output optical signal, and can realize the switch state control of the output port, and the control mode is flexible and widely applicable.

[0024] 3. The application adopts a complementary metal oxide semiconductor (CMOS) process to manufacture a highly integrated on-chip multi-channel filter, realizing miniaturization and high-performance integration of the device.

[0025] 4. In the control method of the on-chip hybrid filter combined with MZI and MRR of the application, on the basis that the power applied to the phase shifters of the two MRR filter modules corresponds to the same, the output light signals can be further precisely phase modulated by adjusting the power applied to the front side phase shifter and / or the rear side phase shifter, so that a set of spectrum-complementary light signals and a set of spectrum-identical light signals can be simultaneously output from the four output ports, and the adjustment process is convenient and flexible. The spectrum-complementary light signals can be used to improve the signal quality and anti-interference ability, and in optical imaging, the complementary spectrum can help to realize higher imaging quality, and in an optical communication system, the complementary spectrum can be used for simultaneous transmission of multi-wavelength signals, increasing the bandwidth and data transmission capacity of the system. The spectrum-identical light signals can enhance the signal processing ability, and in an optical communication system, the same spectrum can be used to realize more complex signal processing functions, can realize wavelength division multiplexing, can provide signal redundancy, and improve the capacity and flexibility of the system. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a structural schematic diagram of a double straight waveguide micro-ring resonator;

[0027] Figure 2 is a structural schematic diagram of a self-coupling micro-ring resonator;

[0028] Figure 3 is a structural schematic diagram of the MRR filter module in the on-chip hybrid filter combined with MZI and MRR embodiment of the application;

[0029] Figure 4 is a structural schematic diagram of the on-chip hybrid filter combined with MZI and MRR embodiment of the application;

[0030] Figure 5 is the output image of each port in the on-chip hybrid filter combined with MZI and MRR embodiment of the application; wherein a is the output image of the In1 port and the Out1 port, and b is the output image of the In2 port and the Out2 port;

[0031] Figure 6 is the output image of the In2 port and the Out2 port after adjusting the center wavelength in the on-chip hybrid filter combined with MZI and MRR embodiment of the application;

[0032] Figure 7 is the output image of the In2 port and the Out2 port after extinction ratio tuning in the on-chip hybrid filter combined with MZI and MRR embodiment of the application;

[0033] Figure 8 is the output image of In2 port and Out2 port after adjusting the front side phase shifter and the rear side phase shifter in the on-chip hybrid filter embodiment of the present application combining MZI and MRR;

[0034] Figure 9 is the output image of In2 port and Out2 port after tuning the free spectral range in the on-chip hybrid filter embodiment of the present application combining MZI and MRR.

[0035] BRIEF DESCRIPTION OF DRAWINGS

[0036] 01 - lower coupling region, 02 - upper coupling region;

[0037] 1 - fifth beam splitter, 2 - sixth beam splitter, 3 - phase shifter, 4 - front side phase shifter, 5 - rear side phase shifter, 6 - third beam splitter, 7 - fourth beam splitter, 8 - first beam splitter, 9 - second beam splitter. DETAILED DESCRIPTION

[0038] The existing double straight waveguide micro-ring resonator is composed of a micro-ring and two straight waveguides through evanescent field coupling, and the structure is shown in Figure 1 The optical signal is input from In01 port into the lower straight waveguide, coupled with the micro-ring to form the lower coupling region 01, a part of the optical signal continues to transmit in the lower straight waveguide and is output through Out01 port; the remaining optical signal is coupled into the micro-ring, and the optical signal in the micro-ring transmits in the counterclockwise direction, is coupled near the upper straight waveguide to form the upper coupling region 02, a part of the optical signal is coupled into the upper straight waveguide and is output through Out02 port, and the remaining optical signal continues to transmit in the micro-ring in the counterclockwise direction and is coupled again at the lower coupling region 01, a part of the optical signal is coupled into the lower straight waveguide and is output through Out01 port, and the remaining optical signal continues to transmit in the micro-ring in the counterclockwise direction.

[0039] The double straight waveguide micro-ring resonator is a symmetrical structure, so the transmission process of the optical signal input from In02 port into the upper straight waveguide is the same as the transmission process of the optical signal input from In01 port into the lower straight waveguide.

[0040] The structure of the double straight waveguide micro-ring resonator is changed to make the optical signal interfere, that is, the optical signal output from Out01 port is introduced into Out02 port, that is, the output optical signal of Out01 port is taken as the input optical signal of Out2 port, so that the two optical signals interfere in the micro-ring, thereby obtaining a self-coupling micro-ring resonator, as shown in Figure 2As shown, the self-coupled micro-ring resonator is based on the structural adjustment of the double straight waveguide micro-ring resonator, the optical signal is input from the In port, the interference occurs in the micro-ring, so that a part of the optical signal is output from the Out port, and the remaining optical signal is output reversely from the In port, therefore, the In port is also called the Re port.

[0041] The self-coupled micro-ring resonator forms complementary output spectrum lines at the In port and the Out port, in order to realize the function of tuning, the present application improves the self-coupled micro-ring resonator, adds a plurality of phase shifters 3 on the self-coupled micro-ring resonator, adjusts the power of the phase shifters 3 to realize the phase modulation of the optical signal, thereby changing the output spectrum line, forming an MRR filter module, and the structure is as shown in Figure 3 .

[0042] The on-chip hybrid filter combined with the MZI and the MRR of the present application increases the MRR filter module on the basis of the Mach-Zehnder interferometer (MZI), including the MZI structure and two MRR filter modules, as shown in Figure 4 .

[0043] The MZI structure includes a first beam splitter 8, a second beam splitter 9, an MZI upper arm and an MZI lower arm; two input ends of the first beam splitter 8 are respectively used for connecting external devices, and are respectively marked as In1 port and In2 port, and two output ends thereof are respectively connected to one end of the MZI upper arm and the MZI lower arm. Two input ends of the second beam splitter 9 are respectively connected to the other end of the MZI upper arm and the MZI lower arm, and two output ends thereof are respectively used for connecting external devices, and are respectively marked as Out1 port and Out2 port.

[0044] The two MRR filter modules are respectively located on the MZI upper arm and the MZI lower arm, and the MRR filter module includes a third beam splitter 6, a fourth beam splitter 7, a fifth beam splitter 1 and a sixth beam splitter 2. One input end of the third beam splitter 6 is connected to one output end of the first beam splitter 8, the other input end is connected to one input end of the fourth beam splitter 7, and a phase shifter 3 is arranged between the two input ends; the other input end of the fourth beam splitter 7 is connected to one output end of the fifth beam splitter 1, and a phase shifter 3 is arranged between the two input ends; one output end of the third beam splitter 6 is connected to one input end of the fifth beam splitter 1, and a phase shifter 3 is arranged between the two input ends, and the other output end is connected to the other input end of the fifth beam splitter 1; one output end of the fourth beam splitter 7 is connected to one input end of the sixth beam splitter 2, and the other output end is connected to the other input end of the sixth beam splitter 2, and a phase shifter 3 is arranged between the two input ends; the other output end of the fifth beam splitter 1 is connected to one output end of the sixth beam splitter 2; the other output end of the sixth beam splitter 2 is connected to one input end of the second beam splitter 9, and the output end is the Out port of the MRR module; the above-mentioned ports are all connected by waveguides.

[0045] Further comprising a front side phase shifter 4 and a rear side phase shifter 5, the front side phase shifter 4 is arranged between the output end of the first beam splitter 8 and one input end of the third beam splitter 6 of the lower arm of the MZI; the rear side phase shifter 5 is arranged between the other input end of the fourth beam splitter 7 and the output end of the fifth beam splitter 1 of the lower arm of the MZI. For the convenience of phase modulation, the parameters of the two MRR filtering modules in the embodiment are the same, the phase shifters 3 are all arranged to be the same power, and only by adjusting the power of the front side phase shifter 4 and / or the rear side phase shifter 5, the phase modulation of the optical signal is realized, so as to change the output spectral line and realize the function of tunable.

[0046] The phase shifter 3, the front side phase shifter 4 and the rear side phase shifter 5 in the application are all micro heaters, by adjusting the power applied to the micro heater, the phase modulation of the optical signal is realized, and the micro heater has the advantages of simple manufacturing process, low power consumption and high phase shifting efficiency.

[0047] The first beam splitter 8 and the second beam splitter 9 are both multimode interferometers, the multimode interferometer has the advantages of simple manufacturing process, small size, suitable for optical integration, low insertion loss and large bandwidth. The waveguide and each beam splitter are all made of silicon or silicon oxide or silicon nitride or a III-V material or lithium niobate material. The proportion of the two optical signals output by all the beam splitters is 1:1.

[0048] In order to improve the integration of the above-mentioned on-chip hybrid filter, the application adopts CMOS process to realize the on-chip multi-channel filter.

[0049] The optical signal transmission process of the MRR filtering module of the application is specifically as follows:

[0050] The initial optical signal is input to the third beam splitter 6 and is divided into two parts, one part of the optical signal is transmitted to the fifth beam splitter 1 through the phase shifter 3, and the other part of the optical signal is directly transmitted to the fifth beam splitter 1, the fifth beam splitter 1 combines the two parts of the optical signal and divides them into two parts, which are respectively recorded as the first optical signal and the second optical signal.

[0051] The first light signal is transmitted to the fourth beam splitter 7 through the phase shifter 3, and is divided into two parts by the fourth beam splitter 7. One part of the light signal is transmitted to the sixth beam splitter 2 through the phase shifter 3, and the other part of the light signal is directly transmitted to the sixth beam splitter 2. The sixth beam splitter 2 combines and divides the two parts of the light signal into two parts, which are the third light signal and the fourth light signal. The third light signal is transmitted to the second beam splitter 9, and the fourth light signal is transmitted to the fifth beam splitter 1. The light signal transmitted to the fifth beam splitter 1 is divided into two parts. One part of the light signal is transmitted to the third beam splitter 6 through the phase shifter 3, and the other part of the light signal is directly transmitted to the third beam splitter 6. The third beam splitter 6 combines and divides the two parts of the light signal into two parts. One part of the light signal is transmitted to the first beam splitter 8, and the other part of the light signal is transmitted to the fourth beam splitter 7 through the phase shifter 3, and then the transmission path is the same as the first light signal.

[0052] The second light signal is directly transmitted to the sixth beam splitter 2 and divided into two parts. One part of the light signal is transmitted to the fourth beam splitter 7 through the phase shifter 3, and the other part of the light signal is directly transmitted to the fourth beam splitter 7. The fourth beam splitter 7 combines and divides the two parts of the light signal into two parts. One part of the light signal is transmitted to the third beam splitter 6 through the phase shifter 3, and then the transmission path is the same as the initial light signal input to the third beam splitter 6. The other part of the light signal is transmitted to the fifth beam splitter 1 through the phase shifter 3, and then the transmission path is the same as the fourth light signal described above.

[0053] According to the above analysis of the light signal transmission process, after the initial light signal is input from the In1 or In2 port, a part of the light signal in the MZI upper arm and the MZI lower arm is respectively output to the second beam splitter 9 through the MRR module, and then combined and divided by the second beam splitter 9 to form two light signals, which are output from the Out1 port and the Out2 port in the forward direction. Another part of the light signal is combined and divided by the first beam splitter 8 to form another two light signals, which are output from the In1 port and the In2 port in the reverse direction. Therefore, the In1 port and the In2 port are also respectively referred to as the Re1 port and the Re2 port.

[0054] The control method of the above-mentioned on-chip hybrid filter combined with MZI and MRR is as follows:

[0055] The first beam splitter 8 receives the initial optical signal inputted from outside and divides it into two beams, forming an upper light path and a lower light path. The optical signal of the upper light path is filtered by the MRR filtering module of the upper arm of the MZI, and a part of the optical signal is transmitted forward to the second beam splitter 9, and the rest of the optical signal is transmitted reversely to the first beam splitter 8. The optical signal of the lower light path is filtered by the MRR filtering module of the lower arm of the MZI, and a part of the optical signal is transmitted forward to the second beam splitter 9, and the rest of the optical signal is transmitted reversely to the first beam splitter 8. The second beam splitter 9 combines and divides the optical signals transmitted forward by the upper light path and the lower light path, and two forward output optical signals are obtained. The first beam splitter 8 combines and divides the optical signals transmitted reversely by the upper light path and the lower light path, and two reverse output optical signals are obtained. The four optical signals are outputted as the output of the filter. By adjusting the power of the phase shifter 3 in the two MRR filtering modules, the phase modulation of the output optical signals of the upper arm and the lower arm of the MZI is realized. The phase modulation of the output optical signal of the lower light path can also be realized by adjusting the power of the front phase shifter 4 and the rear phase shifter 5. In the embodiment, the power applied to the phase shifter 3 of the two MRR filtering modules is the same. By adjusting the power applied to the front phase shifter 4 and / or the rear phase shifter 5, the phase modulation of the optical signal of the lower light path is realized, and finally a group of frequency spectrum complementary optical signals and a group of frequency spectrum same optical signals are outputted, as shown in Figures 5 to 9 .

[0056] The optical signal is inputted at the In1 port, and the power applied to the front phase shifter 4 and the rear phase shifter 5 is 0. By adjusting the power applied to the phase shifter 3 in the two MRR filtering modules, the optical signals outputted at the In1, In2, Out1 and Out2 ports are obtained, as shown in Figure 5 . As shown in the figure, the signals outputted at the Out1 and Out2 ports are a group of frequency spectrum same signals, the signals outputted at the In1 and In2 ports are a group of frequency spectrum same signals, the signals outputted at the Out2 and In2 ports are a group of frequency spectrum complementary signals, and the signals outputted at the Out1 and In1 ports are a group of frequency spectrum complementary signals.

[0057] On the basis of b in Figure 5 , the power applied to the phase shifter between the third beam splitter 6 and the fourth beam splitter 7 in the two MRR filtering modules is reduced, and the optical signals outputted at the In2 and Out2 ports are obtained, as shown in Figure 6 . By comparing b in Figure 5 , it is known that the left shift of the output signal is realized, and therefore the present application can realize the tunable center wavelength.

[0058] On the basis of b in Figure 5 , the power applied to the phase shifter between the sixth beam splitter 2 and the fourth beam splitter 7 in the two MRR filtering modules is increased, and the optical signals outputted at the In2 and Out2 ports are obtained, as shown in Figure 7 . By comparing b in Figure 5As can be seen from the b, the waveform of the output signal is changed, so that the extinction ratio can be adjusted.

[0059] In Figure 5 b, the power applied to the phase shifter between the fifth beam splitter 1 and the third beam splitter 6 in the two MRR filtering modules is increased, and the power applied to the phase shifter between the sixth beam splitter 2 and the fourth beam splitter 7 in the two MRR filtering modules is increased, so that the optical signals output at the In2 and Out2 ports are as shown in Figure 9 b, the transmittance of the In2 and Out2 ports is close to 0, and compared with Figure 5 b, the waveform of the output signal is changed, so that the free spectral range can be adjusted.

[0060] In Figure 5 b, the power applied to the front side phase shifter 4 and the rear side phase shifter 5 is adjusted, so that the optical signals output at the In2 and Out2 ports are as shown in Figure 8 b, the transmittance of the In2 and Out2 ports is close to 0, and compared with Figure 5 b, it can be considered that Figure 5 b, the In2 and Out2 ports are open, while the In2 and Out2 ports are closed at this time, so that by adjusting the power applied to the front side phase shifter 4 and the rear side phase shifter 5, the output port switch state can be accurately controlled.

Claims

1. An on-chip hybrid filter combining MZI and MRR, comprising an MZI structure; the MZI structure comprising a first beam splitter (8), a second beam splitter (9), an MZI upper arm, and an MZI lower arm; The two input ends of the first beam splitter (8) are respectively used to connect to external devices, and the two output ends thereof are respectively connected to one end of the MZI upper arm and the MZI lower arm; The two input ends of the second beam splitter (9) are respectively connected to the other end of the MZI upper arm and the other end of the MZI lower arm, and the two output ends thereof are respectively used to connect to external devices; Its characteristics are: It also includes MRR filter modules located in the upper arm and the lower arm of the MZI respectively; The MRR filter module includes a third beam splitter (6), a fourth beam splitter (7), a fifth beam splitter (1), and a sixth beam splitter (2); One input end of the third beam splitter (6) is connected to one output end of the first beam splitter (8), and the other input end is connected to one input end of the fourth beam splitter (7), with a phase shifter (3) provided between the two; the other input end of the fourth beam splitter (7) is connected to one output end of the fifth beam splitter (1), with a phase shifter (3) provided between the two; One output end of the third beam splitter (6) is connected to one input end of the fifth beam splitter (1) with a phase shifter (3) provided therebetween, and the other output end is connected to the other input end of the fifth beam splitter (1); one output end of the fourth beam splitter (7) is connected to one input end of the sixth beam splitter (2), and the other output end is connected to the other input end of the sixth beam splitter (2) with a phase shifter (3) provided therebetween; The other output end of the fifth beam splitter (1) is connected to an output end of the sixth beam splitter (2); The other output end of the sixth beam splitter (2) is connected to one of the input ends of the second beam splitter (9); All the above ports are connected by waveguides.

2. The on-chip hybrid filter combining MZI and MRR according to claim 1, characterized in that: The MZI lower arm is provided with a front phase shifter (4) between the output end of the first beam splitter (8) and an input end of the third beam splitter (6); The MZI lower arm is provided with a rear phase shifter (5) between the other input end of the fourth beam splitter (7) and the output end of the fifth beam splitter (1).

3. The on-chip hybrid filter combining MZI and MRR according to claim 1 or 2, characterized in that: The phase shifter (3), the front phase shifter (4), and the rear phase shifter (5) are all micro heaters.

4. The on-chip hybrid filter combining MZI and MRR according to claim 3, characterized in that: The first beam splitter (8) and the second beam splitter (9) are both multimode interferometers.

5. The on-chip hybrid filter combining MZI and MRR according to claim 4, characterized in that: The materials of the waveguide, the first beam splitter (8), the second beam splitter (9), the third beam splitter (6), the fourth beam splitter (7), the fifth beam splitter (1), and the sixth beam splitter (2) are all silicon, silicon oxide, silicon nitride, III-V group materials, or lithium niobate materials; The MZI structure and MRR filter module are manufactured using CMOS technology.

6. A method for controlling an on-chip hybrid filter combining MZI and MRR according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1: Input the initial optical signal into the first beam splitter (8), and the first beam splitter (8) splits the initial optical signal into two beams, forming an upper optical path and a lower optical path, which are respectively transmitted to the MZI upper arm and the MZI lower arm; Step 2: After the optical signal of the upper optical path is filtered by the MRR filter module of the upper arm of the MZI, a portion of the optical signal is transmitted forward to the second beam splitter (9), and the rest is transmitted backward to the first beam splitter (8); After the optical signal of the lower optical path is filtered by the MRR filter module of the MZI lower arm, a portion of the optical signal is transmitted forward to the second beam splitter (9), and the rest is transmitted backward to the first beam splitter (8); The second beam splitter (9) combines and splits the optical signals transmitted in the forward direction of the upper optical path and the lower optical path to obtain two optical signals output in the forward direction; the first beam splitter (8) combines and splits the optical signals transmitted in the reverse direction of the upper optical path and the lower optical path to obtain two optical signals output in the reverse direction; Step 3, adjusting the power applied to the phase shifter (3) and / or the front phase shifter (4) and / or the rear phase shifter (5) to achieve phase modulation of the optical signal of the upper optical path and / or the lower optical path.

7. The control method of the on-chip hybrid filter combined with MZI and MRR according to claim 6, characterized in that: Step 3 is as follows: The power applied to the phase shifters (3) of the two MRR filter modules is the same, and the power applied to the front phase shifter (4) and / or the rear phase shifter (5) is adjusted to perform phase modulation on the optical signal of the lower optical path.

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