A programmable extensible photonic processing core fabric

Abstract

The application relates to a programmable and scalable photonic processing core based on a Mach-Zehnder interferometer and a micro-ring resonator unit structure, comprising a tunable basic unit TBU, the TBU comprising a tunable optical coupler and a micro-ring resonator type optical switch. The tunable optical coupler is internally provided with a phase shifter, and the adjustment of the coupling coefficient is realized through a control circuit; the micro-ring resonator type optical switch is a double-ring structure, and a phase shifter is arranged on the ring waveguide to adjust the resonant wavelength and the passband or stopband bandwidth of the optical switch. A plurality of core cells are connected to the tunable basic unit TBU to form core cells of a predetermined shape, and the optical signals are transmitted in a predetermined optical path according to the set optical coupling coefficient, phase and wavelength range. The photonic processing core can be reconfigured into a symmetric MZI, an asymmetric MZI, a micro-ring resonator, a linear optical computing network, a wavelength division multiplexing / demultiplexing system and a beam forming, etc.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of integrated microwave photonics, and particularly relates to a programmable and scalable photonic processing core based on a Mach-Zehnder interferometer and a micro-ring resonator unit structure. BACKGROUND

[0002] Photonic Integrated Circuit (PIC) has become a powerful platform for building complex optical systems. By integrating high-density optical elements on a single chip and assisting with programming and other means to apply appropriate electrical control signals to active optical devices, a wide range of application functions can be achieved. Compared with the advantages of integrated circuits in digital operation, integrated optical circuits have more outstanding advantages in transmitting and processing analog signals.

[0003] Currently, PIC follows the manufacturing process of integrated electronic circuits and follows the development path of electronic products. However, most PICs are designed in the way of Application Specific Photonic Integrated Circuit (ASPIC), which is designed for specific target applications, so it is difficult to use the designed and processed ASPIC for other aspects, and there is also an iteration process of demonstration-simulation-processing-verification, which results in high economic cost and time cost.

[0004] In recent years, the concept of Programmable Photonic Circuit (PPC) has attracted widespread attention. Its characteristics are that the optical function of the integrated optical circuit can be changed through electrical programming, so as to be applied to various scenes. On the other hand, it can also realize the rapid function verification of some complex optical circuits, which is the optical counterpart of the field programmable gate array in the electrical field.

[0005] The common PPC architecture currently proposed is Recirculating Programmable Photonic Circuit (R-PPC), which is characterized by the presence of a plurality of core cells of specific shapes in the entire optical circuit, including triangles, squares or hexagons. The cell itself constitutes a "recirculating" optical loop. The cells can be connected to each other to form a larger integrated optical circuit, which can perform more complex functions. In addition, R-PPC is also suitable for parallel operators, high-speed optical signal processors, quantum interferometers, etc.

[0006] According to the prior scheme, the R-PPC is configured with a 2*2 Mach-Zehnder Interferometer (MZI) type tunable optical coupler based on the thermo-optic effect, and the modulation efficiency of the Mach-Zehnder Interferometer MZI type tunable optical coupler based on the thermo-optic effect is low, the length of the tunable optical coupler is long, which leads to a narrow free spectral range of functions such as micro-ring resonator (Micro-ring Resonator), and the optical response of the Mach-Zehnder Interferometer MZI itself is a wide spectrum response, and the optical function with high wavelength correlation requirement such as wavelength division multiplexing / demultiplexing, time domain differentiator and the like cannot be competent. SUMMARY

[0007] The purpose of the present application is to retain the advantages of the original Mach-Zehnder Interferometer MZI type tunable optical coupler in the R-PPC scheme, such as flexible optical path, linear calculation and the like, to provide the potential for the current programmable and expandable photonic processing core to realize the function with high wavelength correlation.

[0008] To achieve the above purpose, the technical scheme adopted by the present application is to adopt a programmable and expandable photonic processing core based on a Mach-Zehnder Interferometer and a micro-ring resonator unit structure, characterized in that a new type of tunable basic unit TBU is proposed, which directly connects a 2*2 MRR type optical switch on the basis of the Mach-Zehnder Interferometer MZI type tunable optical coupler adopted in the current common R-PPC architecture, and utilizes the resonant spectral characteristics in the MRR optical response, thereby introducing a certain wavelength selectivity for the tunable basic unit TBU adopted. The construction and expansion of the core cell based on the tunable basic unit TBU can obtain the programmable and expandable photonic processing core of the R-PPC architecture with higher functionality.

[0009] The programmable and expandable photonic processing core structure of the present application is based on a Mach-Zehnder Interferometer and a micro-ring resonator unit, comprising a semiconductor substrate, a plurality of core cells located inside the semiconductor substrate, and a control circuit located on the surface of the semiconductor substrate.

[0010] The core cell is one of a square unit structure, a regular hexagonal unit structure (the specific configuration adopted in the patent) and a triangular unit structure, adjacent core cells share edges to form a network structure with a plurality of core cells. The core cell transmits the optical signal in a predetermined optical path according to the set optical coupling coefficient, phase and wavelength range;

[0011] At least one core cell is connected with an input port to receive an externally input optical signal, and at least one core cell is connected with an output port to output a processed optical signal.

[0012] The core cell comprises a plurality of tunable basic units (TBU), adjacent tunable basic units are connected through waveguides, the tunable basic units TBU in each core cell are connected into a hexagonal cell structure, a square cell structure or a triangular cell structure, for performing optical domain processing such as filtering or arbitrary power splitting on optical signals coupled to the plurality of interconnected tunable basic units TBU; for example, when the core cell is a regular hexagonal cell structure, the tunable basic units TBU are respectively located on each side of the core cell.

[0013] The control circuit is arranged directly above the plurality of interconnected tunable basic units TBU, for adjusting the phase setting of at least one phase modulator in the corresponding tunable basic unit TBU, to realize the functional change of the programmable and expandable photonic processing core.

[0014] Further, the tunable basic unit TBU comprises a 2×2 tunable optical coupler based on a Mach-Zehnder interferometer and a 2×2 optical switch based on a micro-ring resonator, two output ports of the 2×2 tunable optical coupler are directly connected to two input ports of the 2×2 micro-ring resonator type optical switch.

[0015] Further, the tunable optical coupler comprises two couplers, two interference arms connected between the two couplers, and a first phase shifter on one of the interference arms, for realizing control of the power ratio after splitting, and a control electrode is further arranged on the first phase shifter.

[0016] Further, the tunable optical coupler comprises three states, namely a Bar state, a Cross state and a Coupler state, and the tunable optical coupler determines one of the bar state, the coupling coupler state and the cross state of the processed optical signal according to the size of the phase shift.

[0017] When the phase shift of the first phase shifter is , the tunable optical coupler is in the Bar state, at this time there is no coupling of transmission signals between waveguides, and the optical signal exists in the existing optical path transmission.

[0018] When the phase shift of the first phase shifter is , the tunable optical coupler is in the Cross state, and the coupling between the waveguides reaches the maximum.

[0019] When the phase shift of the first phase shifter is between 0 and π, there is partial coupling between the waveguides, and the transmission optical path exists overlap.

[0020] Further, the micro-ring resonator type optical switch includes a cross waveguide, two ring waveguides, and a second phase shifter and a third phase shifter arranged on the two ring waveguides respectively, and control electrodes arranged on the second phase shifter and the third phase shifter. The independent control of two micro-ring resonance peaks is completed by the phase shifters on the ring waveguides. The two ring waveguides are arranged in central symmetry about the center of the cross waveguide, and the resonance peak offset can be achieved by adjusting the in-ring phase shifter of one of the ring waveguides without affecting the single-ring optical switch path, so as to adjust the filter bandwidth. The two output ports of the tunable optical coupler are respectively connected to the input ports of the two straight waveguides.

[0021] The two rings have the same radius to ensure that the resonance peaks are aligned; and the coupling distances of the two rings and the straight waveguides are the same to achieve a better notch depth or peak height.

[0022] Further, the passing or filtering wavelength range of the optical signal processed in the 2x2 micro-ring resonator type optical switch in the tunable basic unit TBU is determined according to the size of the phase shift of the ring waveguide in the MRR.

[0023] Further, the micro-ring resonator type optical switch has two states, namely a tuning state one and a tuning state two.

[0024] When the phase shift of the second phase shifter and the third phase shifter is , the optical switch is in the tuning state one, and the tuning state one refers to that only one high-extinction-ratio notch peak is output after tuning.

[0025] When the phase shift of the second phase shifter and the third phase shifter is , the optical switch is in the tuning state two, and the tuning state two refers to that the resonance wavelengths of the two rings are offset, and two notch peaks appear in the output spectrum after tuning.

[0026] An application system based on the programmable and expandable photonic processing core structure includes at least one physical layer and a software layer; a specific application function is mapped and configured as an execution block of the programmable and expandable photonic processing core structure, including the following steps:

[0027] Step 1, selecting a required basic application;

[0028] Step 2, inputting specific performance requirements;

[0029] Step 3, planning the number of core cells and the area of the programmable and expandable photonic processing core to be used to constitute an execution block;

[0030] The application function is mapped to the execution block through a control circuit.

[0031] Further, steps 1-3 are configured by a user through the software layer or automatically configured by the software layer, and the control circuit layer and the physical layer are transparent to the user.

[0032] Compared with the prior art, the present application has the following beneficial effects: the programmable and expandable photonic processing core based on the Mach-Zehnder interferometer and the micro-ring resonator unit structure of the present application is based on the R-PPC architecture which has been relatively mature, and the tunable basic unit TBU is replaced by a 2*2 MZI type tunable optical processor + a 2*2 MRR type optical switch from the original Mach-Zehnder interferometer MZI type tunable optical processor. On the one hand, the problem of too small free spectral range and difficult to achieve critical coupling when the R-PPC architecture is directly reconstructed into a micro-ring resonator related application is solved. On the other hand, by individually tuning the ring structure of the MRR type optical switch in the tunable basic unit TBU, wavelength-related functions such as wavelength division multiplexer / demultiplexer, time domain differentiator and adjustable delay line can be realized, greatly improving the reconfigurability and versatility of the photonic processing core. In addition, within the free spectral range of the micro-ring, the MRR type optical switch is in a transparent state to the Mach-Zehnder interferometer MZI type tunable optical coupler, that is, the spectral response of the micro-ring does not affect the spectral characterization of the Mach-Zehnder interferometer MZI, so that other functions that can be realized by the current R-PPC can be realized in this wavelength range, and the spectral resource utilization is more abundant. In addition, the tuning of each tunable basic unit TBU is independent of each other and does not interfere with each other, and the control is simple. By using integrated photon technology, it also has the advantages of small size and low power consumption. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is an application scheme diagram of the programmable and expandable photonic processing core system structure of the present application;

[0034] Figure 2 is a core cell shape schematic diagram of the programmable and expandable photonic processing core of the present application.

[0035] Figure 3 is a structure schematic diagram of the tunable basic unit TBU used by the programmable and expandable photonic processing core of the present application.

[0036] Figure 4 is a 2*2 MZI type tunable optical coupler in the tunable basic unit TBU and a state diagram when it is actually used.

[0037] Figure 5 is a 2*2 MRR type tunable optical switch structure in the tunable basic unit TBU and a state diagram when it is actually used.

[0038] Figure 6 is a curve diagram of the transmittance and the phase difference between the two ports of the Mach-Zehnder interferometer MZI type tunable optical coupler in the tunable basic unit TBU about the change of heating power under the input light of 1550 nm.

[0039] Figure 7 is the output spectrum of the MRR type tunable optical switch in the tunable basic unit TBU under different control voltages.

[0040] Figure 8 is the spectral response diagram of the programmable extensible photonic processing core under a partial configuration.

[0041] Among them, the photonic processing core structure 100, the coupling device 110, the photodetector 120, the radio frequency modulator 130, the external cavity laser 140, the electrical control signal input port 150, the radio frequency signal connector 160; Computer 170;

[0042] Core cell 101;

[0043] Hexagonal cell structure 200, square cell structure 210, triangular cell structure 220;

[0044] Tunable basic unit TBU 300, optical structure 310, control electrode 301, first phase shifter 311, second phase shifter 312, third phase shifter 313;

[0045] Tunable optical coupler 400, input light 401, coupler output beam two 403, coupler output beam one 402, Bar state 410, Cross state 420, Coupler state 430;

[0046] Resonator type optical switch 500, wide spectrum input light 501, tuned output spectrum one 502, tuned output spectrum two 503, tuning state one 510, tuning state two 520. DETAILED DESCRIPTION

[0047] The present application will be further described below in conjunction with the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other. The drawings show some examples of the use of the present application, and should not be interpreted as being limited to the use examples described herein.

[0048] The present application proposes a programmable extensible photonic processing core structure based on Mach-Zehnder interferometer and micro-ring resonator cell structure. As shown in FIG. 1, the photonic processing core structure 100 includes a coupling device 110, a photodetector 120, a radio frequency modulator 130, an external cavity laser 140, an electrical control signal input port 150, a radio frequency signal connector 160, and a computer 170. Figure 1As shown, it is a schematic diagram of the overall application system using the programmable extensible photonic processing core disclosed in the present application. The example programmable reconfigurable photonic processing core structure 100 disclosed in the present application comprises a semiconductor substrate, a plurality of core cells inside the semiconductor substrate. The input and output optical fiber is coupled with the on-chip waveguide through the coupling device 110, realizing the external light input or the external output of the processed optical signal. As an example of the use of the present application, the programmable extensible photonic processing core structure 100 can be connected with the photodetector 120, outputting the microwave signal carried at a specific wavelength, thereby realizing the signal processing of the photodetector 120. In addition, as an example of the use of the present application, the programmable extensible photonic processing core structure 100 can be connected to the radio frequency modulator 130, controlling the input signal from the radio frequency modulator 130 through 300, thereby performing related operations as a radio frequency filter in the optical domain. In addition, as an example of the use of the present application, the programmable extensible photonic processing core can be connected with the external cavity laser 140, thereby realizing the function of optical parallel matrix multiplier. The above-mentioned photonic processing core structure 100, input and output coupler 110, photodetector 120, radio frequency modulator 130 and external cavity laser 140 are the optical physical layer of the overall application system, which directly performs various optical operations or processing tasks and realizes the direct input and output of optical and electrical signals.

[0049] Figure 1 In the above-mentioned example, the electrical control signal input port 150 is arranged in the peripheral or upper layer (three-dimensional packaging) of the optical physical layer in the manner as shown, which is connected with the control electrode laid on each core cell 101, and the tuning control of the tunable basic unit TBU 300 is realized by applying a direct current control signal to the corresponding electrical control signal input port 150, realizing the change of factors such as splitting ratio, resonant wavelength and filtering wavelength. The radio frequency signal connector 160 provides the input of corresponding radio frequency signals for the physical layer, such as the radio frequency modulator 130. The two constitute the control circuit layer of the overall application system, which is used to receive the provided electrical input signal, thereby completing the function and performance switching of the optical physical layer.

[0050] Figure 1In order to achieve the above-mentioned purposes, the application provides a programmable and scalable photonic processing core based on a Mach-Zehnder interferometer and a micro-ring resonator unit structure. The programmable and scalable photonic processing core comprises a control circuit layer and a photonic physical layer. The control circuit layer is connected to the photonic physical layer, and the control circuit layer is connected to a high-level hardware device represented by a computer 170. The computer 170 is connected to the control circuit layer, and the control software loaded in the computer 170 is used to realize the following functions: 1, selecting a required basic application; 2, inputting specific performance requirements; 3, planning the number of core cells and the area of the programmable and scalable photonic processing core to be used; and 4, mapping the application function to the execution block through the control circuit layer. The software converts the user input requirements into information required by the input port of each electrical control signal of the control circuit layer and outputs the information, so that the user can use the programmable and scalable photonic processing core without understanding the specific structure of the control circuit layer and the photonic physical layer, that is, the lower layer is transparent to the user.

[0051] Figure 2 The programmable and scalable photonic processing core based on the Mach-Zehnder interferometer and the micro-ring resonator unit structure is used. The shape of the core cell is shown in the schematic diagram, wherein Figure 2 (a) in the above-mentioned schematic diagram is a hexagonal cell; Figure 2 (b) in the above-mentioned schematic diagram is a square cell; Figure 2 (c) in the above-mentioned schematic diagram is a triangular cell, and the core cell comprises a plurality of basic tunable units (TBU). The adjacent basic tunable units are connected through a waveguide. The connection mode between the basic tunable units (TBU) can be a hexagonal cell structure 200, a square cell structure 210 and a triangular cell structure 220. The hexagonal cell structure is used in the example of the application, and has higher energy efficiency at the node.

[0052] Figure 3 The structure of the tunable basic unit (TBU) 300 used in the programmable and scalable photonic processing core based on the Mach-Zehnder interferometer and the micro-ring resonator unit structure is shown in the schematic diagram. The tunable basic unit (TBU) 300 comprises an optical structure 310 and a matched control electrode 301. The optical structure 310 is a novel tunable basic unit (TBU) directly connected in cascade by a 2×2 MZI type tunable optical coupler and a 2×2 MRR type optical switch. The control of the tunable optical coupler is realized by a first phase shifter 311 on the interference arm, and the power ratio control is completed. The control of the resonator type optical switch is realized by a second phase shifter 312 and a third phase shifter 313 on the ring waveguide, and the independent control of the two micro-ring resonance peaks is completed. That is, the control electrode 301 shown in the figure comprises a control electrode of the first phase shifter 311, a control electrode of the second phase shifter 312 and a control electrode of the third phase shifter 313.

[0053] Figure 4The 2x2 MZI type tunable optical coupler 400 in the tunable basic unit TBU 300 used is shown in the schematic diagram and the state when it is actually used. In the figure, the input light 401 is input from one port of the tunable optical coupler, and is split into two beams of light by the tunable optical coupler 400, which are the coupler output beam two 403 and the coupler output beam one 402, respectively. The power ratio of the two output beams is quantitatively controlled by the first phase shifter 311 on the interference arm. Specifically, the tunable optical coupler has three states, which are the Bar state 410, the Cross state 420 and the Coupler state 430. When the phase shift amount of the phase shifter is , the tunable optical coupler is in the Bar state 410, at which time there is no coupling of the transmission signal between the waveguides, and the optical signal is transmitted along the existing optical path. When , the tunable optical coupler is in the Cross state 420, at which time the coupling between the waveguides reaches the maximum, and the optical signal is transmitted from the cross port. When , the tunable optical coupler is in the Coupler state 430, at which time there is partial coupling between the waveguides, and there is a certain overlap in the transmission optical path. Quantitatively, the ratio of the light amplitude of the coupler output beam one 402 to the input light is , and the ratio of the light amplitude of the coupler output beam two 403 to the input light is

[0054] Figure 5 The structure schematic diagram of the 2x2 MRR type tunable optical switch 500 in the tunable basic unit TBU 300 and the state when it is actually used are shown. In the figure, the wide spectrum input light 501 is input from one port of the tunable optical switch, and is output as the tuned output spectrum one 502 and the tuned output spectrum two 503 after being processed by the device, which are similar to the Through end and the Drop end of the add-drop type micro-ring resonator. Specifically, when , the optical switch is in the tuning state one 510, and since the coupling distance and the radius of the micro-rings in the device are the same, the resonant wavelengths of the two rings are aligned and coincide, and there is only one high extinction ratio notch peak in the tuned output spectrum one 502 (corresponding to the high transmittance peak of the tuned output spectrum two 503); when , the optical switch is in the tuning state two 520, and the resonant wavelengths of the two rings are misaligned, and there are two notch peaks in the tuned output spectrum two 502. Theoretically, the extinction ratios of the two notch peaks are smaller than that in the tuning state one 510 (and the peak transmittance of the tuned output spectrum two 503 should also be smaller than that in the tuning state one 510).

[0055] In order to verify the practical application of the present application, a verification example is given for illustration.

[0056] The verification example adopts the finite-difference time-domain method and the transmission matrix method to jointly calculate and analyze. The material system used in the simulation is SOI, and the specific parameters used are: a rectangular waveguide process is adopted, and the waveguide cross-sectional size is 500nm*220nm. The splitter used in the MZI type tunable optical coupler is a 2*2 multimode interferometer, and the size of the multimode waveguide region is 41.8μm*6μm, and the interference arm waveguide length is 200μm. The coupling pitch in the MRR type optical switch is 100nm, the ring radius is 10μm, and the center cross waveguide width waveguide size is 5.5μm*1.4μm. In order to reduce the loss, Taper waveguide is introduced when the above straight waveguide and wide waveguide are connected to reduce the size. The tuning means used in the verification example is thermal tuning, which is based on the SOI material system, and the thermo-optic coefficient of the core silicon material is 1.84*10 -4 , and the thermo-optic coefficient of the cladding / silicon dioxide substrate is 1*10 -5 , and there is a difference of one order of magnitude, so the effective refractive index of the waveguide can be effectively controlled by heating the silicon waveguide.

[0057] Figure 6 The transmittance and two-port phase difference of the Mach-Zehnder interferometer MZI type tunable optical coupler in the tunable basic unit TBU300 are shown under the input light of 1550nm, and the change curves of the transmittance and two-port phase difference with respect to the heating power are shown. It can be seen from Figure 6 that the power required to switch the working state of the Mach-Zehnder interferometer MZI type tunable optical coupler from the Bar state 410 to the Cross state 420 is about 30.5mW.

[0058] Figure 7 The output spectrum of the MRR type tunable optical switch in the tunable basic unit TBU300 under different control voltages is shown. Figure 7 In (a) of the figure, the voltages applied to the second phase shifter 312 and the third phase shifter 313 are V1=0V and V2=0V respectively; Figure 7 In (b) of the figure, V1=0.1V and V2=0V; Figure 7 In (c) of the figure, V1=0.5V and V2=0V. From the applied voltage, it can be seen that the MRR type optical switch is sensitive to heating, and a small voltage can cause an objective wavelength shift.

[0059] External light enters the photonic processing core from the coupling device 110, and the user inputs the related requirements using the software layer, and inputs the control signal to the corresponding control electrode of the selected photonic processing core area through the control circuit layer, so as to perform processing or operation on the input light, and feedback the user's expected spectral response or optical function or other forms of output. Figure 8 Part of the optical function display of the photonic processing core of a certain scale constructed by the finite-difference time-domain method and the transmission matrix method is shown, which verifies its powerful and rich functionality. For example,Figure 8 (a)-(e) show the advantage functions of the photonic processing core compared with the traditional R-PPC architecture photonic processor, that is, high wavelength correlation function. Figure 8 (a) in the figure is a wavelength division multiplexing / demultiplexing system, and the output wavelength and spectral bandwidth can be changed by thermal tuning. (b) in the figure is a bandpass / bandstop filter, and the passband or stopband of the filter can be changed by tuning the resonant wavelength of the micro-ring. Figure 8 (c) in the figure is a time-domain differentiator, and the in-loop loss of the micro-ring can be ignored due to the small radius of the micro-ring, so that the single ring is close to the critical coupling state, and the phase shift of the micro-ring at the resonant wavelength is close to π according to the phase frequency characteristic. Figure 8 (d) to (e) are partial reproductions of the functions that can be realized by the traditional R-PPC architecture photonic processor, and good reproduction is obtained in the free spectral range of the micro-ring. Figure 8 (d) in the figure is an asymmetric MZI; Figure 8 (e) in the figure is an MRR (six TBUs are composed).

[0060] Compared with the prior art, the programmable and expandable photonic processing core based on the Mach-Zehnder interferometer and micro-ring resonator unit structure proposed by the present application is based on the currently relatively mature R-PPC architecture, and the tunable basic unit TBU 300 is replaced by a 2×2 MZI type tunable optical processor + a 2×2 MRR type optical switch from the original Mach-Zehnder interferometer MZI type tunable optical processor. Firstly, the problem of too small free spectral range and difficulty in achieving critical coupling when the original R-PPC architecture is directly reconstructed into a micro-ring resonator related application is solved. On the other hand, by tuning the ring structure of the MRR type optical switch in the tunable basic unit TBU 300, wavelength correlation functions such as wavelength division multiplexer / demultiplexer, time-domain differentiator and adjustable delay line can be realized, greatly improving the reconfigurability and versatility of the photonic processing core. In addition, in the free spectral range of the micro-ring, the MRR type optical switch is in a transparent state to the Mach-Zehnder interferometer MZI type tunable optical coupler, that is, the spectral response of the micro-ring does not affect the spectral characterization of the Mach-Zehnder interferometer MZI, so that other functions that can be realized by the current R-PPC can be realized in this wavelength range, and the spectral resource utilization is more abundant. In addition, the tuning of each tunable basic unit TBU 300 is independent of each other and does not interfere with each other, and the control is simple. By using integrated photon technology, it also has the advantages of small size and low power consumption.

[0061] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled persons in the art, without departing from the principles of the present application, a number of improvements and supplements can be made, and these improvements and supplements should also be regarded as the protection scope of the present application.

Claims

1. A programmable extensible photonic processing core fabric, comprising: The semiconductor substrate, a plurality of core cells inside the semiconductor substrate, and a control circuit on the surface of the semiconductor substrate are included. The plurality of core cells are connected to each other, and the control circuit is connected to the core cells. The core cell includes a plurality of tunable basic units (TBUs), the adjacent tunable basic units are connected through waveguides, the tunable basic units (TBUs) in each core cell are connected into a hexagonal cell structure, a square cell structure or a triangular cell structure. The control circuit is used for modulating the tunable basic units (TBUs). The tunable basic unit (TBU) includes a 2x2 tunable optical coupler based on a Mach-Zehnder interferometer and a 2x2 optical switch based on a micro-ring resonator, two output ports of the 2x2 tunable optical coupler are directly connected to two input ports of the 2x2 micro-ring resonator type optical switch.

2. The programmable extensible photonic processing core structure of claim 1, wherein, The tunable optical coupler includes two couplers, two interference arms connected between the two couplers, and a first phase shifter on one of the interference arms, and is used for controlling the power ratio of the split beams.

3. The programmable extensible photonic processing core structure of claim 2, wherein, The tunable optical coupler includes three states, namely a straight-through bar state, a cross state and a coupling coupler state. The tunable optical coupler determines the state of the processed optical signal according to the size of the phase shift. When the first phase shifter phase shift amount The tunable optical coupler is in the Bar state, at this time, there is no coupling of the transmission signal between the waveguides, and the optical signal is transmitted along the existing optical path. When the first phase shifter phase shift amount When the first phase shifter phase shift amount When the first phase shifter phase shift amount When the first phase shifter phase shift amount When the first phase shifter phase shift amount When the first phase shifter phase shift amount When the first phase shifter phase shift amount When the first phase shifter phase When the first phase shifter phase shift is between 0 and π There is partial coupling between the waveguides and there is overlap of the transmission optical paths.

4. The programmable extensible photonic processing core structure of claim 1, wherein, The micro-ring resonator type optical switch includes a cross waveguide, two ring waveguides, and a second phase shifter and a third phase shifter arranged on the two ring waveguides respectively. The two ring waveguides are arranged in central symmetry about the center of the cross waveguide, and the two output ports of the tunable optical coupler are connected to the input ports of the two straight waveguides respectively. The two ring waveguides have the same ring radius, and the coupling distances of the two rings to the cross waveguide are the same.

5. The programmable extensible photonic processing core structure of claim 4, wherein, The micro-ring resonator type optical switch determines the pass or filter band range of the processed optical signal according to the size of the phase shift of the ring waveguide.

6. The programmable extensible photonic processing core structure of claim 5, wherein, The micro-ring resonator type optical switch has two states, namely tuning state one and tuning state two. When the phase shift amounts of the second phase shifter and the third phase shifter are When the phase shift amounts of the second phase shifter and the third phase shifter are When the phase shift amounts of the second phase shifter and the third phase shifter are When the phase shift amounts of the second phase shifter and the third phase shifter are When the phase shift amounts of the second phase shifter and the third phase shifter are When the phase shift amounts of the second phase shifter and the third phase shifter are

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