An optical chip

Abstract

The application provides an optical chip, comprising: an M*N optical switch matrix, comprising M first transmission paths and N second transmission paths, a first optical switch being arranged at the intersection of the first transmission path and the second transmission path, M and N being positive integers, M first processing units corresponding to the first transmission paths, used for converting signal light into TE mode signal light and inputting the TE mode signal light from both sides of the matrix in a first direction; N second processing units corresponding to the second transmission paths, used for outputting TE mode signal light from a second direction and converting the signal light into signal light comprising TE and TM modes and outputting the signal light. In the optical chip, two polarized signals can be processed simultaneously by using one optical switch matrix, polarization-independent optical signal exchange is realized, and the number, power consumption, size and cost of optical switches are reduced.

Description

Technical Field

[0001] This application relates to the field of optical communication, and more specifically, to an optical chip. Background Technology

[0002] With the emergence and widespread adoption of new industries such as 5G, IoT, big data, and cloud computing, the rapidly increasing data transmission volume and expanding business scenarios are placing increasingly higher demands on the performance and cost of optical communication systems. In the field of data center optical transmission, traditional signal switching functions are implemented based on electrical switching chips. The bandwidth and number of ports for switching signals are limited by the heat dissipation, chip size, and number of pins of the electrical switching chips. Currently, the heat dissipation of electrical switching chips is nearing its physical limit, and the benefits brought by the upgrade of CMOS (complementary metal-oxide-semiconductor) process technology have been exhausted. The industry widely believes that the evolution will gradually move towards high-speed optical switching systems. In the field of metropolitan area transport networks, with the adoption of wavelength division multiplexing (WDM) technology, metropolitan area networking requires low-cost optical layer solutions. The wavelength selective switch (WSS) solution used in traditional switching methods is too costly for metropolitan area transport networks. The approach based on arrayed waveguide gratings (AWG) and optical switching matrices can provide a low-cost and flexible optical layer solution for metropolitan area transport networks, and also has the potential to provide a low-cost, small-size optical switching solution for backbone networks in addition to WSS.

[0003] Optical switches are core components for signal switching in optical networks, and their performance directly impacts the network's performance. The polarization-independent nature of optical switches is crucial for optical switching systems because the polarization state of optical signals in ordinary single-mode fiber is typically uncertain and often changes over time. If an optical switching system cannot achieve polarization independence, it will malfunction. However, most photonic devices on current integrated optical chip platforms are polarization-sensitive, meaning they respond differently to transverse electric (TE) and transverse magnetic (TM) modes of optical signals. In many cases, photonic devices can only function correctly for one polarization mode and fail for the other. Therefore, implementing polarization-independent optical switch matrices on integrated optical chips presents a significant technical challenge. Summary of the Invention

[0004] This application provides an optical chip that, through structural design, can achieve polarization independence on an integrated optical chip using an optical switch matrix.

[0005] In a first aspect, an optical chip is provided, comprising: an M×N optical switch matrix, including M first transmission paths and N second transmission paths, wherein the M first transmission paths are used to transmit signal light in a first direction, and the N second transmission paths are used to transmit signal light in a second direction, the first direction and the second direction intersect, and a first optical switch is disposed at the intersection of the M first transmission paths and the N second transmission paths, where M and N are positive integers, and the first optical switch is denoted as S. ij Where i∈[1,M], j∈[1,N], any first transmission path includes a first input side and a second input side, and the first input side is connected to S i1 Connection, the second input side is connected to S iN The connection, any second transmission path includes a first output side and a second output side, the first output side and S 1j Connection, the second output side is connected to S Mj connect; M first processing units are corresponding one-to-one with the M first transmission paths. Each first processing unit includes an input port, a first polarization rotating beam splitter (PSR), a first waveguide, and a second waveguide. The input port is connected to the first polarization rotating beam splitter (PSR), the first polarization rotating beam splitter (PSR) is connected to the first waveguide and the second waveguide, the first waveguide is connected to the first input side of the first transmission path corresponding to the first processing unit, and the second waveguide is connected to the second input side of the first transmission path corresponding to the first processing unit. The input port is used for the input of a first signal light. The first polarization rotating beam splitter (PSR) can convert the first signal light into a second signal light with a first polarization mode and a third signal light with the first polarization mode, and transmit the second signal light to the first waveguide and the third signal light to the second waveguide. N second processing units, each corresponding to one of the N second transmission paths. Each second processing unit includes a third waveguide, a fourth waveguide, a second polarization rotating beam splitter (PSR), and an output port. The third waveguide is connected to the first output side of the second transmission path corresponding to the second processing unit, and the fourth waveguide is connected to the second output side of the second transmission path corresponding to the second processing unit. The third waveguide is used to transmit the fourth signal light of the first polarization mode to the second polarization rotating beam splitter (PSR). The fourth waveguide is used to transmit the fifth signal light of the first polarization mode to the second polarization rotating beam splitter (PSR). The second polarization rotating beam splitter (PSR) is used to convert the fourth and fifth signal lights into a sixth signal light including the first and second polarization modes. The output port is used for outputting the sixth signal light.

[0006] The first mode can be TE mode, and the second mode can be TM mode.

[0007] In this application, a chip structure comprising an M×N optical switch matrix, M first processing units, and N second processing units enables signal light input from M input ports to be output from any of the N output ports. Two polarization signals can be processed simultaneously using a single optical switch matrix, achieving polarization-independent optical signal exchange, thereby reducing the number of optical switches, power consumption, size, and cost. Furthermore, since both the first and second signal lights processed by the polarization rotation beam splitter (PSR) are input to the same matrix, the problem of either the first or second signal light being too weak, leading to optical path monitoring failure and malfunction, is prevented.

[0008] In conjunction with the first aspect, in some implementations of the first aspect, in the M×N optical switch matrix: S io The third port and S io+1 The first port connection, O, has a value range of 1, ..., N-1; S pj The fourth port and S p+1jThe second port is connected, and the value of P ranges from 1 to M-1. Any one of the first optical switches includes: a first port, a second port, a third port, and a fourth port, used for inputting and / or outputting signal light. A control unit is used to control the connection mode between the first port, the second port, the third port, and the fourth port. The connection mode includes a first mode and a second mode. In the first mode, signal light input from the first port can be output from the third port but not from the second port or the fourth port; and signal light input from the second port can be output from the fourth port but not from the first port or the third port; and signal light input from the third port can be output from the first port but not from the second port or the fourth port; and signal light input from the fourth port can be output from the second port but not from the first port or the third port. In the second mode, signal light input from the first port can be output from the fourth port but not from the second port or the third port; and signal light input from the second port can be output from the third port but not from the first port or the fourth port.

[0009] This can also be understood as O and P belonging to two dimensions. In the first direction, the first port and the third port of adjacent optical switches are connected; in the second direction, the second port and the fourth port of adjacent optical switches are connected. In the optical switches of the optical chip, the connection state of the four ports in the optical switch is controlled by the control unit to control the signal light parameters. This allows the signal light to be input into the optical switch from two directions (the first port and the third port) when the optical switch is used in an optical switch matrix. The output port of the signal light is determined by the switching mode of the control circuit, thus realizing the application in the optical chip.

[0010] In conjunction with the first aspect, in some implementations of the first aspect, any one of the first optical switches includes: a first port group, including the first port and the second port; a second port group, including the third port and the fourth port; a beam splitter, including a first arm and a second arm, the beam splitter being capable of splitting the input signal light into two sub-signal lights and enabling the sub-signal lights to be transmitted in the first arm and the second arm respectively, a first side of the beam splitter being connected to two ports in the first port group, and a second side of the beam splitter being connected to two ports in the second port group; and a controller for modulating the phase of the signal light input from a port in one port group and transmitted in the first arm and / or the second arm, so as to control the light intensity of the signal light output from each port of the other port group.

[0011] In conjunction with the first aspect, in some implementations of the first aspect, any one of the first optical switches includes Mach number 1. Zengel interferometer.

[0012] In the optical switch of this application, the output port of the optical switch is determined by the phase of the modulated signal light, thereby specifically realizing the structure of the optical switch. It has the advantages of not requiring precise feedback control circuitry, having a wide wavelength response range, and being able to switch multiple wavelengths simultaneously. In some implementations, the optical switch can be Mach 6. Structure of the Mach-Zehnder Interferometer (MZI).

[0013] In conjunction with the first aspect, in some implementations of the first aspect, any one of the first optical switches includes: a fifth waveguide, including a first port and a third port; a sixth waveguide, including a second port and a fourth port; the fifth waveguide intersecting the sixth waveguide; a resonant cavity located at the angle between the fifth waveguide and the sixth waveguide, wherein when the wavelength of the signal light coincides with the resonant wavelength of the resonant cavity, the signal light can be coupled from one waveguide to the resonant cavity and then to another waveguide; and a controller for modulating the resonant wavelength of the resonant cavity.

[0014] In conjunction with the first aspect, in some implementations of the first aspect, any one of the first optical switches includes a microring resonator.

[0015] In the optical switch of this application, the optical switch structure is specifically implemented by controlling the resonant wavelength of the resonant cavity, resulting in low insertion loss, sensitive response, and low switching voltage required by the control circuit. In some implementations, the control unit can be a micro-ring resonant cavity structure.

[0016] In conjunction with the first aspect, in some implementations of the first aspect, the waveguide included in the controller is made of an electro-optically tunable material, and the waveguides outside the controller are made of different materials than the waveguides included in the controller. That is, the waveguide structure in the optical chip uses different materials, thereby reducing the loss caused by signal light transmission in different optical paths. The specific choice of electro-optic tunability is determined according to the actual situation; for example, the material can be lithium niobate, etc.

[0017] In a second aspect, a wavelength division multiplexing (WDM) system is provided, including an arrayed waveguide grating (AWG) and an optical chip as described in the first aspect, wherein: the arrayed waveguide grating (AWG) is used to perform wavelength division multiplexing processing on signal light; and the optical chip is used to control the output port of the signal light after wavelength division multiplexing processing. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of an optical chip according to this application.

[0019] Figure 2 This is a schematic diagram of the structure of an optical switch according to this application.

[0020] Figure 3 This is a schematic diagram of another optical switch structure in this application.

[0021] Figure 4 This is a schematic diagram of the port connectivity status of the optical switch in the first mode.

[0022] Figure 5 This is a schematic diagram of the port connectivity status of the optical switch in the second mode.

[0023] Figure 6 This is a schematic diagram of another optical switch structure in this application.

[0024] Figure 7 This is a schematic diagram of the port connectivity status of the optical switch in the first mode.

[0025] Figure 8 This is a schematic diagram of the port connectivity status of the optical switch in the second mode. Detailed Implementation

[0026] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0027] First, the terms “comprising” and “having” and any variations thereof used in the embodiments of this application shown below are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products or devices.

[0028] Second, in the embodiments of this application, the words "exemplarily" or "for example" are used to indicate examples, illustrations, or descriptions. Embodiments or designs described as "exemplarily" or "for example" should not be construed as being more preferred or advantageous than other embodiments or designs. The use of words such as "exemplarily" or "for example" is intended to present the relevant concepts in a specific manner for ease of understanding.

[0029] Third, the terms "first," "second," and various numerical designations used in the textual descriptions or drawings of the embodiments of this application shown below are merely for descriptive convenience and are not intended to describe a specific order or sequence, nor are they used to limit the scope of the embodiments of this application. For example, they are used in the embodiments of this application to distinguish different transceivers.

[0030] With the emergence and widespread adoption of new industries such as 5G, IoT, big data, and cloud computing, the rapidly increasing data transmission volume and expanding business scenarios are placing increasingly higher demands on the performance and cost of optical communication systems. In the field of data center optical transmission, traditional signal switching functions are implemented based on electrical switching chips. The bandwidth and number of ports for switching signals are limited by the heat dissipation, chip size, and number of pins of the electrical switching chips. Currently, the heat dissipation of electrical switching chips is nearing its physical limit, and the benefits brought by the upgrade of CMOS (complementary metal-oxide-semiconductor) process technology have been exhausted. The industry widely believes that the evolution will gradually move towards high-speed optical switching systems. In the field of metropolitan area transport networks, with the adoption of wavelength division multiplexing (WDM) technology, metropolitan area networking requires low-cost optical layer solutions. The wavelength selective switch (WSS) solution used in traditional switching methods is too costly for metropolitan area transport networks. The approach based on arrayed waveguide gratings (AWG) and optical switching matrices can provide a low-cost and flexible optical layer solution for metropolitan area transport networks, and also has the potential to provide a low-cost, small-size optical switching solution for backbone networks in addition to WSS.

[0031] Optical switches are core components for signal switching in optical networks, directly impacting network performance. An ideal optical switch should simultaneously possess polarization independence, fast switching, low insertion loss, low power consumption, and small size, making it crucial for efficient optical switching. The polarization independence characteristic of optical switches is vital for optical switching systems because the polarization state of optical signals in ordinary single-mode fiber is typically uncertain and often changes over time. If an optical switching system cannot achieve polarization independence, it will malfunction. However, most photonic devices on current integrated optical chip platforms are polarization-sensitive, meaning they respond differently to transverse electric (TE) and transverse magnetic (TM) modes of optical signals. In many cases, photonic devices can only function correctly for one polarization mode, failing for the other. Therefore, implementing a polarization-independent optical switch matrix on integrated optical chips presents significant technical challenges.

[0032] To address the aforementioned issues, this application provides an optical chip that, through structural design, achieves polarization independence on an integrated optical chip using a single optical switch matrix.

[0033] The optical switches, optical switch matrices, and optical chips involved in this application can be implemented using integrated waveguide structures. The specific waveguide materials used are determined according to the actual situation, and this application does not impose any restrictions on them.

[0034] Figure 1 This is a schematic diagram of the structure of an optical chip according to this application. Figure 1 As shown, the optical chip 100 may include an M×N optical switch matrix, M first processing units, and N second processing units. Wherein: An M×N optical switch matrix includes M first transmission paths and N second transmission paths. The first transmission paths transmit signal light in a first direction, and the second transmission paths transmit signal light in a second direction. The first and second directions intersect, and the angle between them can be determined based on actual conditions; for example, the angle between the first and second directions can be as follows: Figure 1 The angle shown is 90°, but it can also be set to 60°, 80°, etc. A first optical switch is installed at the intersection of M first transmission paths and N second transmission paths, where M and N are positive integers. For ease of description, the first optical switch will be denoted as S. ij Where i∈[1,M], j∈[1,N]. In the M first transmission paths, any row includes a first input side, a second input side, and the first input side is connected to S. i1 Connection, second input side and S iN Connection; in N second transmission paths, any one includes a first output side and a second output side, wherein the first output side is connected to S 1j Connect, second output side to S Mj connect.

[0035] There are M first processing units, each corresponding to one of the M first transmission paths. Each first processing unit includes an input port 111, a first polarization splitter and rotater (PSR) 112, a first waveguide 113, and a second waveguide 114. The input port 111 is connected to the first PSR 112, and the first PSR 112 is connected to the first waveguide 113 and the second waveguide 114.

[0036] Input port 111 is used for inputting a first signal light; the first PSR 112 can convert the first signal light input from input port 111 into a second signal light with a first polarization mode and a third signal light with a first polarization mode, and transmit the second signal light to the first waveguide 113 and the third signal light to the second waveguide 114. The first waveguide 113 is connected to the first input side of the first transmission path corresponding to the first processing unit, and the second waveguide 114 is connected to the second input side of the first transmission path corresponding to the first processing unit. The first waveguide 113 is used to input the second optical signal into the M×N optical switch matrix from the first input side in a first direction, and the second waveguide 114 is used to input the third optical signal into the M×N optical switch matrix from the second input side in a first direction.

[0037] There are N second processing units, each corresponding to one of the N second transmission paths. Each of the N second processing units includes a third waveguide 121, a fourth waveguide 122, a second PSR 123, and an output port 124. The third waveguide 121 and the fourth waveguide 122 are connected to the second PSR 123, and the second PSR 123 is connected to the output port 124.

[0038] The third waveguide 121 is connected to the first output side of the second transmission path corresponding to the second processing unit, and the fourth waveguide 124 is connected to the second output side of the second transmission path corresponding to the second processing unit. The third waveguide 121 is used to output the fourth signal light of the first polarization mode from the M×N optical switch matrix to the second PSR 123 in the second direction. The fourth waveguide 124 is used to output the fifth signal light of the first polarization mode from the M×N optical switch matrix to the second PSR 123 in the second direction. The second PSR 123 is used to convert the fourth signal light and the fifth signal light into a sixth signal light including the first polarization mode and the second polarization mode, and output the sixth signal light from the output port 124.

[0039] In such Figure 1 The optical chip shown employs a chip structure comprising an M×N optical switch matrix, M first processing units, and N second processing units. This allows signal light input from the M input ports to be output from any of the N output ports. A single optical switch matrix can simultaneously process two polarization signals, enabling polarization-independent optical signal exchange, thereby reducing the number of optical switches, power consumption, size, and cost. Furthermore, since both the first and second signal lights processed by the polarization rotation beam splitter (PSR) are input to the same matrix, it prevents the first or second signal light from being too weak, which could lead to optical path monitoring failure and malfunction.

[0040] The first polarization mode can be the transverse electric (TE) mode, and the second polarization mode can be the transverse magnetic (TM) mode.

[0041] In an M×N optical switch matrix, the specific connection method between the optical switches can be: S io The third port and S io+1 The first port connection, O, has a value range of 1, ..., N-1; S pj The fourth port and S p+1j The second port is connected, and the value of P ranges from 1 to M-1. This can also be understood as O and P belonging to two dimensions. In the first direction, the first port of an adjacent optical switch is connected to the third port; in the second direction, the second port of an adjacent optical switch is connected to the fourth port. That is, in the first direction, signal light can be input to the optical switch from two directions (the first port and the third port). The control circuit switches the optical switch to either the first or second mode to determine the output port of the signal light. In the first mode, the signal light input from the first and third ports can only be transmitted along the first direction; in the second mode, the signal light input from the first and third ports is redirected to be transmitted in the second direction.

[0042] Figure 2 This is a schematic diagram of the structure of an optical switch according to this application, such as... Figure 2 As shown, the optical switch 200 may include a first port 210, a second port 220, a third port 230, a fourth port 240, and a control unit 250. Wherein: Port 210 (first port), 120 (second port), 230 (third port), and 240 (fourth port) are used for inputting and / or outputting optical signals. Figure 2 For example, the first port 210 and the third port 230 can be used to input and / or output signal light in the first direction, and the second port 220 and the fourth port 240 can be used to input and / or output signal light in the second direction.

[0043] The control unit 250 is used to control the connection mode between the ports, including a first mode and a second mode.

[0044] like Figure 2As shown in Figure (a), in the first mode, the first port 210 and the third port 230 are optically connected, and the second port 220 and the fourth port 240 are optically connected. Signal light input from the first port 210 can be output from the third port 230, but not from the second port 220 or the fourth port 240; signal light input from the second port 220 can be output from the fourth port 240, but not from the first port 210 or the third port 230; signal light input from the third port 230 can be output from the first port 210, but not from the second port 220 or the fourth port 240; signal light input from the fourth port 240 can be output from the second port 220, but not from the first port 210 or the third port 230.

[0045] like Figure 2 As shown in (b), in the second mode, the signal light input from the first port 210 can be output from the fourth port 240, but cannot be output from the second port 220 or the third port 230; the signal light input from the second port 220 can be output from the third port 230, but cannot be output from the first port 210 or the fourth port 240.

[0046] In this application, by using a control unit to control the signal light parameters, the connection state of the four ports in the optical switch is controlled, so that when the optical switch is used in the optical switch matrix, the signal light can be input to the optical switch from two directions (the first port and the third port), and the output port of the signal light is determined by the switching mode of the control circuit, thus realizing its application in the optical chip.

[0047] As a kind of Figure 1 and Figure 2 In this case, an example of signal light input and output on an optical chip is provided so that signal light input from the second row can be output from the second column: The first signal light can be input from the input port 111 of the first processing unit corresponding to the second first transmission path. After passing through the first PSR 112, it is split into a second signal light in TE mode and a third signal light in TE mode. The second signal light is transmitted from the first waveguide 113 to the first input side of the second first transmission path, and the third signal light is transmitted from the second waveguide 114 to the second input side of the second first transmission path. In the second first transmission path, the first optical switch S... 22 The first optical switch is set to the second mode, while the other optical switches are set to the first mode. Thus, the first signal light input from the first input side is transmitted to the first optical switch S in the first direction. 22 From S 22 The first port input, the fourth port output, and the second signal light input from the second input side are transmitted in the first direction to the first optical switch S. 22The signal light is input from the third port and output from the second port. The second signal light is transmitted along the second direction and output from the second output side as an M×N optical switch matrix, then transmitted along the fourth waveguide 122. The third signal light is transmitted along the second direction and output from the first output side as an M×N optical switch matrix, then transmitted along the third waveguide 121. The TE-mode second signal light and the TE-mode third signal light are combined at the second PSR 123 and, after polarization processing, converted into a fourth signal light including TE and TM modes, which is output from the output port 124. This achieves the switching processing of two polarization signals using a single optical switch array.

[0048] Figure 3 This is a schematic diagram of another optical switch structure in this application, as shown below. Figure 3 As shown, the optical switch 300 may include a first port group, a second port group, a beam splitter, and a controller 320. Wherein: The first port group includes the first port and the second port; The second port group includes the third and fourth ports; The beam splitter includes a first arm 311 and a second arm 312. A first side of the beam splitter is connected to a first port group, and a second side is connected to a second port group. The beam splitter can split an input signal light into two sub-signal beams, which are then transmitted in the first arm 311 and the second arm 312, respectively.

[0049] Controller 320, wherein the controller may be in the form of a control electrode, for modulating the phase of the signal light transmitted in the first arm 311 and / or the second arm 312 to control the intensity of the signal light output from each port of another port group.

[0050] For example, such as Figure 3 As shown, control electrodes can be located on both sides of the first arm 311 to modulate the signal light transmitted in the first arm 311. When the signal light enters the beam splitter through the first port group or the second port group, the input signal light is split into two beams, which are transmitted in the first arm 311 and the second arm 312, respectively. The control electrodes change the effective refractive index of the waveguide in the first arm 311 by applying a voltage or injecting charge carriers, thereby controlling the phase of the signal light transmitted in the first arm 311. The signal light transmitted in the first arm 311 and the second arm 312 generates a phase difference, and the specific phase difference controls the light intensity of the signal light at each port, determining the output port of the signal light.

[0051] Figure 4This is a schematic diagram of the port connectivity of the optical switch 300 in the first mode. In the first mode, a signal light input from the first port can be output from the third port but cannot be output from the second or fourth port; a signal light input from the second port can be output from the fourth port but cannot be output from the first or third port; a signal light input from the third port can be output from the first port but cannot be output from the second or fourth port; and a signal light input from the fourth port can be output from the second port but cannot be output from the first or third port. The first mode can be a direct-through mode.

[0052] Figure 5 This is a schematic diagram of the port connectivity of the optical switch 300 in the second mode. In the second mode, the signal light input from the first port can be output from the fourth port, but cannot be output from the second or third port; the signal light input from the second port can be output from the third port, but cannot be output from the first or fourth port, thus realizing the switching mode determining the output port of the signal light. The second mode can be a crossover mode.

[0053] In addition, the control electrodes in the controller can also be located on both sides of the second arm 312 to modulate the phase of the signal light transmitted in the second arm 312. Alternatively, the control electrodes can be located on both sides of the beam splitter 310 to simultaneously modulate the phase of the signal light transmitted in the first arm 311 and the second arm 312. Alternatively, control electrodes can be respectively arranged on both sides of the first arm 311 and the second arm 312; this application does not impose any limitations on this.

[0054] In such Figures 3-5 In the structure shown, the output port of the optical switch is determined by the phase of the modulated signal light, thus realizing the structure of the optical switch. It has the advantages of not requiring precise feedback control circuitry, having a wide wavelength response range, and being able to switch multiple wavelengths simultaneously. In some implementations, the optical switch can be Mach 6. Structure of the Mach-Zehnder Interferometer (MZI).

[0055] Figure 6 This is a schematic diagram of another optical switch structure in this application, as shown below. Figure 6 As shown, the optical switch 400 may include a fifth waveguide 410, a sixth waveguide 420, a resonant cavity 430, and a controller 440, wherein: The fifth waveguide 410 includes a first port and a third port; The sixth waveguide 420 includes the second port and the fourth port, and the fifth waveguide 410 intersects with the sixth waveguide 420.

[0056] The resonant cavity 430 is located at the angle between the fifth waveguide 410 and the sixth waveguide 420. When the wavelength of the signal light coincides with the resonant wavelength of the resonant cavity, the signal light can be coupled from one waveguide to the resonant cavity and then to another waveguide.

[0057] The controller 440 can be in the form of a control electrode and is used to modulate the resonant wavelength of the resonant cavity.

[0058] Figure 7 This is a schematic diagram of the port connectivity of the optical switch 400 in the first mode. In the first mode, the resonant wavelength does not coincide with the wavelength of the signal light transmitted in the fifth waveguide. Therefore, the signal light transmitted in the fifth waveguide 410 cannot couple into the sixth waveguide 420. Consequently, the signal light input from the first port can be output from the third port, but not from the second or fourth port; the signal light input from the second port can be output from the fourth port, but not from the first or third port; the signal light input from the third port can be output from the first port, but not from the second or fourth port; and the signal light input from the fourth port can be output from the second port, but not from the first or third port. At this time, the signal lights transmitted in the fifth waveguide 410 and the sixth waveguide 420 do not affect each other. The first mode can be a crossover mode.

[0059] Figure 8 This is a schematic diagram of the port connectivity state of the optical switch 400 in the second mode. In the second mode, the resonant wavelength does not coincide with the wavelength of the signal light transmitted in the fifth waveguide 410. Therefore, the signal light transmitted in the fifth waveguide cannot couple into the sixth waveguide 420. Consequently, in the second mode, the signal light input from the first port can be output from the fourth port, but not from the second or third port; conversely, the signal light input from the second port can be output from the third port, but not from the first or fourth port. The second mode can be a connectivity mode. This allows the switching mode to determine the output port of the signal light.

[0060] In such Figures 6-8 In the structure shown, the optical switch structure is specifically implemented by controlling the resonant wavelength of the resonant cavity, resulting in low insertion loss, sensitive response, and low switching voltage required by the control circuit. In some implementations, the control unit can be a micro-ring resonant cavity structure.

[0061] In some implementations, such as Figures 3-8 In the structure shown, the waveguide included in the controller is made of an electro-optically tunable material, while the waveguides outside the controller are made of different materials. That is, the waveguide structures in the optical chip use different materials, thereby reducing signal light loss caused by transmission in different optical paths. The specific choice of the electro-optically tunable material is determined based on the actual situation; for example, it could be lithium niobate.

[0062] In some implementations, the optical chip in this application can be manufactured using a heterogeneous integration platform, meaning that the waveguide structure in the optical chip uses different materials. For example, the optical switch can be manufactured using a first material, and the first processing unit and the second processing unit can be manufactured using a second material, thereby reducing the loss caused by the transmission of signal light in different optical paths. The specific selection of the first and second materials is determined according to the actual situation; for example, the materials can be silicon, silicon nitride, lithium niobate, silicon dioxide, etc.

[0063] This application also provides a wavelength division multiplexing system, including an arrayed waveguide grating (AWG) and other components such as... Figure 1 The optical chip shown includes: AWG is used for wavelength division multiplexing of signal light; The optical chip is used to control the output port of the signal light after wavelength division multiplexing.

[0064] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An optical chip, characterized in that, include: An M×N optical switch matrix includes M first transmission paths and N second transmission paths. The M first transmission paths are used to transmit signal light in a first direction, and the N second transmission paths are used to transmit signal light in a second direction. The first and second directions intersect. A first optical switch is disposed at the intersection of the M first transmission paths and the N second transmission paths. M and N are positive integers, and the first optical switch is denoted as S. ij Where i∈[1,M], j∈[1,N], any first transmission path includes a first input side and a second input side, and the first input side is connected to S i1 Connection, the second input side is connected to S iN The connection, any second transmission path includes a first output side and a second output side, the first output side and S 1j Connection, the second output side is connected to S Mj connect; M first processing units are corresponding one-to-one with the M first transmission paths. Each first processing unit includes an input port, a first polarization rotating beam splitter (PSR), a first waveguide, and a second waveguide. The input port is connected to the first polarization rotating beam splitter (PSR), the first polarization rotating beam splitter (PSR) is connected to the first waveguide and the second waveguide, the first waveguide is connected to the first input side of the first transmission path corresponding to the first processing unit, and the second waveguide is connected to the second input side of the first transmission path corresponding to the first processing unit. The input port is used for the input of a first signal light. The first polarization rotating beam splitter (PSR) can convert the first signal light into a second signal light with a first polarization mode and a third signal light with the first polarization mode, and transmit the second signal light to the first waveguide and the third signal light to the second waveguide. N second processing units, each corresponding to one of the N second transmission paths. Each second processing unit includes a third waveguide, a fourth waveguide, a second polarization rotating beam splitter (PSR), and an output port. The third waveguide is connected to the first output side of the second transmission path corresponding to the second processing unit, and the fourth waveguide is connected to the second output side of the second transmission path corresponding to the second processing unit. The third waveguide is used to transmit the fourth signal light of the first polarization mode to the second polarization rotating beam splitter (PSR). The fourth waveguide is used to transmit the fifth signal light of the first polarization mode to the second polarization rotating beam splitter (PSR). The second polarization rotating beam splitter (PSR) is used to convert the fourth and fifth signal lights into a sixth signal light including the first and second polarization modes. The output port is used for outputting the sixth signal light.

2. The optical chip according to claim 1, characterized in that, In the M×N optical switch matrix: S io The third port and S io+1 The first port connection has a value range of 1, ..., N-1; S pj The fourth port and S p+1j For the second port connection, the value of P ranges from 1, ..., M-1; Any one of the first optical switches includes: The first port, the second port, the third port, and the fourth port are used for inputting and / or outputting optical signals. The control unit is configured to control the connectivity mode between the first port, the second port, the third port, and the fourth port, wherein the connectivity mode includes a first mode and a second mode. In the first mode, the signal light input from the first port can be output from the third port, but cannot be output from the second port and the fourth port; and the signal light input from the second port can be output from the fourth port, but cannot be output from the first port and the third port; and the signal light input from the third port can be output from the first port, but cannot be output from the second port and the fourth port; and the signal light input from the fourth port can be output from the second port, but cannot be output from the first port and the third port. In the second mode, the signal light input from the first port can be output from the fourth port, but cannot be output from the second port or the third port; and the signal light input from the second port can be output from the third port, but cannot be output from the first port or the fourth port.

3. The optical chip according to claim 2, characterized in that, Any one of the first optical switches includes: The first port group includes the first port and the second port; The second port group includes the third port and the fourth port; The beam splitter includes a first arm and a second arm. The beam splitter can split the input signal light into two sub-signal lights and transmit the sub-signal lights in the first arm and the second arm respectively. The first side of the beam splitter is connected to two ports in the first port group, and the second side of the beam splitter is connected to two ports in the second port group. A controller is used to modulate the phase of a signal light input from a port in one port group and transmitted in the first arm and / or the second arm, so as to control the intensity of the signal light output from each port in another port group.

4. The optical chip according to claim 2, characterized in that, Any one of the first optical switches includes: The fifth waveguide includes the first port and the third port; the sixth waveguide includes the second port and the fourth port; the fifth waveguide intersects with the sixth waveguide; The resonant cavity is located at the angle between the fifth waveguide and the sixth waveguide. When the wavelength of the signal light coincides with the resonant wavelength of the resonant cavity, the signal light can be coupled from one waveguide to the resonant cavity and then to another waveguide. A controller for modulating the resonant wavelength of the resonant cavity.

5. The optical chip according to claim 1 or 2, characterized in that, Any one of the first optical switches includes Mach. Zengel interferometer.

6. The optical chip according to claim 1 or 2, characterized in that, Each of the first optical switches includes a microring resonator.

7. The optical chip according to claim 3 or 4, characterized in that, in: The waveguide included in the controller is made of an electro-optically tunable material, and the waveguides outside the controller are made of different materials than the waveguides included in the controller.

8. A wavelength division multiplexing system, comprising an arrayed waveguide grating (AWG) and an optical chip as described in any one of claims 1 to 7, wherein: The arrayed waveguide grating (AWG) is used for wavelength division multiplexing of the signal light. The optical chip is used to control the output port of the signal light after wavelength division multiplexing.

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