An array integrated switch frequency shift chip based on acousto-optic deflection

Abstract

The application relates to the technical field of photoelectric fusion and integration, and relates to an array integrated switch frequency shift chip based on acoustooptic deflection. The array integrated switch frequency shift chip comprises a lithium niobate thin film layer, a high acoustooptic merit material thin film layer hetero-integrated with the lithium niobate thin film and an interdigital transducer; the high acoustooptic merit material thin film layer is provided with an acoustooptic deflection structure, the acoustooptic deflection structure comprises a photon deflection unit, an input photon waveguide and an output photon waveguide; and a plurality of acoustooptic deflection structures are cascaded to realize a multi-channel array acoustooptic switch and / or a tunable acoustooptic frequency shift; wherein each photon deflection unit is provided with at least one interdigital transducer. The high acoustooptic merit material is hetero-integrated on the lithium niobate thin film layer, so that the extinction ratio of the on-chip optical switch device is effectively improved; and through cascaded combination of the plurality of acoustooptic deflection structures, a multi-channel optical switch and an on-chip frequency shifter with tunable frequency shift frequency can be formed.

Description

Technical Field

[0001] This application relates to the field of optoelectronic fusion and integration technology, and more specifically, to an array-integrated switch frequency shifting chip based on acousto-optic deflection. Background Technology

[0002] In the global wave of accelerated iteration from information technology to the artificial intelligence era, optoelectronic convergence infrastructure is breaking through towards low energy consumption and high-density integration. Photonic integrated chips, as the supporting carriers for core fields such as 6G communication, quantum sensing, and precision measurement, have seen their performance upgrades become a key issue for industry development. Among them, acousto-optic modulation, with its high extinction ratio switching and precise single-sideband frequency shifting characteristics, is irreplaceable in scenarios such as high-speed optical switching, laser communication, and high-precision signal detection, making its on-chip integration particularly urgent. Traditional high extinction ratio optical switching systems utilize mechanical deflection systems to deflect lasers, or they can be implemented using acousto-optic modulators. Acousto-optic modulators deflect signal light away from the current channel based on the deflection function of sound waves, completing the switching state. When the acousto-optic modulator is working, the deflected light simultaneously completes the single-sideband frequency shifting function; therefore, traditional acousto-optic modulators can also be used as acousto-optic frequency shifters. However, most commercially available acousto-optic modulators are currently manufactured based on bulk piezoelectric crystals such as tellurium dioxide (TeO2) and lithium niobate (LiNbO3). While they are very mature in industrial applications, their discrete structure makes them impossible to integrate with photonic chips, which makes it difficult to meet the urgent need for large-scale, high-density integration and hinders the development of on-chip high extinction ratio switches and frequency shifters.

[0003] While current on-chip integrated solutions include electro-optic modulation based on lithium niobate thin films, their extinction ratio is severely insufficient (30-40 dB) when used as on-chip optical switches, and they cannot achieve tunable frequency shifting over a wide frequency range when used as frequency shifters. Acousto-optic Bragg diffraction can be realized at the chip level using modern micro-nano fabrication processes, known as integrated acousto-optic deflection, which inherits the momentum conservation physics core of bulk acousto-optic Bragg diffraction. In recent years, various researchers have studied on-chip integrated acousto-optic deflectors based on thin-film lithium niobate, but due to the small acousto-optic figure of merit of lithium niobate, its overall efficiency is low, and it cannot achieve large-scale integrated high extinction ratio switch arrays. Furthermore, as a frequency shifter, its shifting frequency is fixed and cannot be tuned. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing integrated acousto-optic modulators, such as low extinction ratio and difficulty in arraying, which prevent tunable frequency shifting operations. This invention provides an array-integrated switch frequency shifting chip based on acousto-optic deflection, which effectively improves the extinction ratio of on-chip optical switching and achieves adjustable frequency shifting.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: An array-integrated switch frequency shifting chip based on acousto-optic deflection is provided, comprising: a lithium niobate thin film layer, a high acousto-optic figure of merit material thin film layer disposed on and heterogeneously integrated with the lithium niobate thin film layer, and an interdigital transducer disposed on the lithium niobate thin film layer; the high acousto-optic figure of merit material thin film layer is provided with an acousto-optic deflection structure, the acousto-optic deflection structure including a photon deflection unit, and an input photon waveguide and an output photon waveguide respectively connected to the photon deflection unit; a plurality of the acousto-optic deflection structures are cascaded to realize a multi-channel array acousto-optic switch and / or tunable acousto-optic frequency shifting; wherein each photon deflection unit is configured with at least one interdigital transducer.

[0006] This invention discloses an array-integrated switch frequency shifter chip based on acousto-optic deflection. High acousto-optic figure of merit (HIGM) materials are heterogeneously integrated on a lithium niobate thin film layer, and acousto-optic deflection structures are set on the HIGM material thin film layer. By cascading and combining several acousto-optic deflection structures, a multi-channel optical switch and an on-chip frequency shifter with tunable frequency shifting can be constructed. This invention effectively improves the extinction ratio of the on-chip optical switching device, and achieves tunable frequency shifting by selecting or controlling interdigital transducers at different positions.

[0007] Furthermore, the high figure of merit (AGM) material thin film layer uses antimony selenide or arsenic selenide. Antimony selenide and arsenic selenide have high AGM and can be heterogeneously integrated with lithium niobate thin films, thereby significantly improving the extinction ratio of the device.

[0008] Furthermore, the lithium niobate thin film layer serves as the substrate of the device, and the bottom of the lithium niobate thin film layer is hollowed out to facilitate the lossless transmission of sound waves.

[0009] Furthermore, each of the photonic deflection units is configured with two input photonic waveguides and two output photonic waveguides. Each input photonic waveguide and each output photonic waveguide integrates a polarization control structure to ensure that the incident light and the outgoing light maintain their original polarization states. The width of the output photonic waveguide is greater than the width of the input photonic waveguide to form non-reciprocal transmission characteristics.

[0010] Furthermore, the photon deflection unit is provided with a sawtooth-shaped surface acoustic wave absorption structure for absorbing and scattering the remaining surface acoustic wave energy.

[0011] Furthermore, the interdigital transducer includes a plurality of interdigital electrodes, and there are structural differences among the plurality of interdigital electrodes. The interdigital transducer has a GS structure, with 20 to 80 pairs of interdigital fingers. Preferably, the interdigital transducer can be a chirped interdigital transducer.

[0012] Furthermore, the thickness of the interdigital transducer is 80nm~200nm, and it can excite acoustic wave signals with a frequency difference of 200MHz~2GHz; the width of the input photonic waveguide and the output photonic waveguide is 300nm~30μm, the thickness is 200nm~500nm, and the operating wavelength is in the communication band.

[0013] Furthermore, when used as an acousto-optic switch, the interdigital transducer is located in the peripheral region of the photon deflection unit. The excited surface acoustic waves diffract the light entering the photon deflection unit. By adjusting the acoustic wave frequency and controlling the deflection angle, the optical power ratio of the output port can be adjusted by regulating the acoustic wave power.

[0014] Furthermore, several of the aforementioned acousto-optic deflection structures are combined into a switch array based on a cross-layer fully interconnected network architecture according to preset requirements to realize N×N multi-channel acousto-optic switching and optical routing, where N is a positive integer greater than or equal to 2.

[0015] Furthermore, when used as an acousto-optic frequency shifter, the interdigital transducer is located in the peripheral region of the photon deflection unit, and the excited surface acoustic wave generates a Doppler frequency shift on the light wave to achieve frequency shifting of the light wave.

[0016] Furthermore, several of the aforementioned acousto-optic deflection structures are combined in series to realize an acousto-optic frequency shifter with tunable output frequency. The two output photonic waveguides of the previous acousto-optic deflection structure are simultaneously connected to the downlink input photonic waveguide of the next adjacent acousto-optic deflection structure. Since each acousto-optic deflection structure is surrounded by an interdigital transducer, the frequency shift can be tunable by selecting different interdigital transducers to enable or disable them. The final frequency shift is obtained by adding the frequencies of the interdigital transducers in the on-state.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention discloses an array-integrated switch frequency shifter chip based on acousto-optic deflection. By cascading several acousto-optic deflection structures, a multi-channel optical switch and an on-chip frequency shifter with tunable frequency shift are formed. By heterogeneously integrating high acousto-optic figure of merit materials, this invention effectively improves the extinction ratio of the on-chip optical switching device. By selecting or controlling interdigital transducers at different positions, the frequency shift can be tunable. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the first-view structure of the acousto-optic deflection device in one embodiment; Figure 2 This is a schematic diagram of the second-view structure of the acousto-optic deflection device in one embodiment; Figure 3 This is a physical schematic diagram of the acousto-optic deflection device in one embodiment; Figure 4 This is a schematic diagram of the overall structure of a multi-channel array optical switch in another embodiment; Figure 5 This is a schematic diagram of a test link structure for the use of a multi-channel array optical switch in one embodiment; Figure 6 This is a schematic diagram of the overall structure of the on-chip tunable frequency shifter in another embodiment; Figure 7 This is a schematic diagram of a test link structure for an on-chip tunable frequency shifter in one embodiment; Figure 8 This is a sound field distribution diagram of surface acoustic wave propagation excited in lithium niobate by an interdigital transducer (IDT) in one embodiment.

[0019] In the attached figures: 1. Lithium niobate thin film layer; 2. High acousto-optic figure of merit material thin film layer; 3. Acousto-optic deflection structure; 31. Photon deflection unit; 32. Input photon waveguide; 33. Output photon waveguide; 34. Polarization control structure; 35. Surface acoustic wave absorption structure; 4. Interdigital transducer. Detailed Implementation

[0020] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0021] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0022] Example 1 This embodiment is a first embodiment of an array-integrated switch frequency shifter chip based on acousto-optic deflection, such as... Figure 1 and Figure 2As shown, in this embodiment, an acousto-optic deflection device is provided, comprising: a substrate layer, a lithium niobate thin film layer 1 (serving as a piezoelectric substrate and support carrier) located on the substrate layer, and a high acousto-optic figure of merit material thin film layer 2 formed on the surface of the lithium niobate thin film layer 1 by a heterogeneous integration process. The material of the high acousto-optic figure of merit material thin film layer 2 can be antimony selenide or arsenic selenide. The high acousto-optic figure of merit material thin film layer 2 is provided with an acousto-optic deflection structure 3, which includes a photon deflection unit 31, and an input photon waveguide 32 and an output photon waveguide 33 respectively connected to the photon deflection unit 31. An interdigital transducer 4 is also provided in the region below the photon deflection unit 31 to generate surface acoustic waves. The interdigital transducer 4 is disposed on the lithium niobate thin film layer 1. The interdigital transducer 4 is composed of interdigital electrodes with a periodic variation according to a certain rule to generate chirped surface acoustic waves and increase the bandwidth of the acousto-optic interaction.

[0023] like Figure 2 As shown, two input photonic waveguides 32 and two output photonic waveguides 33 are provided, located on both sides of the photonic deflection unit 31, respectively. In this embodiment, a polarization control structure 34 is integrated on both the input photonic waveguide 32 and the output photonic waveguide 33 to ensure that the incident and outgoing light maintain their original polarization states. Furthermore, the width of the output photonic waveguide 33 is greater than the width of the input photonic waveguide 32 to form a non-reciprocal transmission characteristic. The polarization control structure 34 can be an asymmetric cross-section rectangular waveguide. By introducing geometric birefringence through the asymmetric geometry of the waveguide width and thickness, the effective refractive index difference between the TE and TM polarization modes is increased, suppressing polarization mode coupling crosstalk and achieving stable polarization-maintaining transmission. This structure can be integrally formed using a single photolithography and reactive ion etching process.

[0024] like Figure 2 As shown, the photon deflection unit 31 is provided with a sawtooth-shaped surface acoustic wave (SAW) absorption structure 35, which is used to absorb and scatter the remaining SAW energy. The SAW absorption structure 35 is located on the upper side of the photon deflection unit 31, and the interdigital transducer 4 is located in the lower region of the acousto-optic deflection unit. The SAW absorption structure 35, located on the upper side of the photon deflection unit 31, is composed of multiple periodically arranged triangular trenches; it is fabricated by defining the triangular array pattern through photolithography and etching vertically downwards. When the residual SAW propagates to this structure, multiple scattering and mode conversions occur at the sidewalls and apex of the triangular trenches, coupling the surface wave energy into substrate bulk waves and dissipating them, thereby suppressing the interference of acoustic wave reflection on the acousto-optic modulation region.

[0025] In this embodiment, the interdigital transducer 4 has a thickness of 80nm~200nm and can excite acoustic wave signals with a frequency difference of 200MHz~2GHz; the input photonic waveguide 32 and the output photonic waveguide 33 have a width of 300nm~30μm and a thickness of 200nm~500nm, and their operating wavelengths are located in the communication band.

[0026] The working principle of the acousto-optic deflection device in this embodiment is as follows: When the device is in operation, the interdigital transducer 4 is controlled by an external driving circuit to generate a frequency-adjustable surface acoustic wave. This surface acoustic wave propagates along the surface of the lithium niobate thin film layer 1 to the photon deflection structure region and undergoes acousto-optic coupling with the incident light wave. When the phase matching condition is met, such as... Figure 3 As shown, the direction of the incident light wave is deflected, and the frequency becomes the superposition of the light wave frequency and the sound wave frequency; subsequently, the light wave after frequency superposition is collected and output by the output waveguide.

[0027] like Figure 8 The image shows the acoustic field diagram of surface acoustic waves propagating on the surface of a heterogeneous integrated lithium niobate thin film and in the acousto-optic coupling region (within the photon deflection unit 31). These acoustic waves form a dynamic acoustic "grating" in the propagation direction, which diffracts the incident light waves.

[0028] Compared with existing on-chip acousto-optic deflection devices, the acousto-optic deflection device provided in this embodiment has the following advantages: the dual-channel acousto-optic deflection device based on thin-film lithium niobate hetero-integrated high extinction ratio can itself be used as a 2×2 optical switch, and can realize the input of the upper and lower channels simultaneously without interference. The two-dimensional surface acoustic wave absorbing structure 35, located at the top of the acousto-optic coupling region (i.e., photonic deflection unit 31), can absorb or scatter surface acoustic waves, allowing excess acoustic wave energy to be dissipated without reflection, thus avoiding affecting the traveling wave transmission effect of surface acoustic waves within the deflection region and improving the deflection efficiency of the acousto-optic deflection device. Waveguide polarization control structures 34 are added to the input photonic waveguide 32 and the output photonic waveguide 33 to avoid mode crosstalk generated during transmission, further improving the switching efficiency of the acousto-optic deflection device. Compared with existing acousto-optic deflection devices, the output port width of the acousto-optic deflection device in this embodiment is much wider than that of the input port, enabling unidirectional transmission and thus exhibiting non-reciprocal transmission characteristics. By utilizing the chirped interdigital transducer 4, a wide-spectrum microwave input is achieved, breaking the narrow bandwidth characteristic of existing acousto-optic deflection devices, which is beneficial for realizing broadband acousto-optic switching and can also realize the single-sideband frequency shift function of light waves. The output port splitting power tuning function can also be realized based on the microwave power change of the input interdigital transducer 4.

[0029] Example 2 This embodiment is a second embodiment of an array-integrated switch frequency shifting chip based on acousto-optic deflection. This embodiment is similar to the first embodiment, except that in this embodiment, several acousto-optic deflection devices provided in the first embodiment are arranged and combined to form the required N×N multi-channel acousto-optic switch.

[0030] Specifically, such as Figure 4 As shown, several of the aforementioned acousto-optic deflection structures 3 are combined according to preset requirements based on a cross-layer fully cross-interconnected network architecture to form a switch array to realize N×N multi-channel acousto-optic switching and optical routing. Each acousto-optic deflection structure 3 is equipped with an interdigital transducer 4 in its surrounding area.

[0031] The working principle of the N×N multi-channel acoustic-optical switching provided in this embodiment is as follows: like Figure 4 As shown, when a light wave passes through the first acousto-optic deflection structure 3 in the first column, the corresponding interdigital transducer 4 connects or disconnects the radio frequency signal. When the interdigital transducer 4 is connected, surface acoustic waves are excited on the surface of the lithium niobate thin film layer 1. The surface acoustic waves propagate through the high acousto-optic figure of merit material thin film layer 2, forming an acousto-optic grating in the region of the two-dimensional photonic deflection unit 31. The light wave is deflected upwards and enters the port of the uplink output photonic waveguide 33, thus being input to the first acousto-optic deflection structure 3 in the second column for the next deflection operation. When the interdigital transducer 4 is disconnected, there is no acousto-optic grating, and the light wave passes directly into the downlink output photonic waveguide 33, being input to the second acousto-optic deflection structure 3 in the second column for the next operation command. By analogy, it can be expanded into a switch array with (N / 2)Log2(N) acousto-optic deflection structures 3 to realize an N×N multi-channel acousto-optic switch, while using the input power of the acoustic wave to realize controllable multi-path routing of optical power.

[0032] This embodiment enables beams input from any port to reach any output port with an ultra-high extinction ratio through any channel by multiple cascades; and by tuning the power of the input interdigital transducer 4, it can achieve arbitrary optical power output ratios, showing unique potential in on-chip array switches and optical routing.

[0033] like Figure 5The diagram shows a performance testing system for the N×N multi-channel acousto-optic switch described in this invention. This testing system is used to verify the acousto-optic switch of the device. Its core components include: a communication band tunable laser (used to provide incident laser of a specific wavelength), a polarization controller (used to adjust the polarization state of the incident laser so that its one-dimensional polarization direction matches the acousto-optic action direction of the device), a signal source (used to output a microwave electrical signal of a specific frequency as the driving signal for the interdigital transducer 4), a photodetector (used to convert the outgoing light signal into an electrical signal to realize light intensity detection), and an oscilloscope (used to receive the electrical signal output by the photodetector, display and record the modulation waveform in real time). The testing process of this testing system is as follows: In the device testing stage, a radio frequency signal of a preset frequency is first applied to the interdigital transducer 4 through a signal source to excite it. The interdigital transducer 4 will excite periodic surface acoustic waves on the surface of the lithium niobate thin film layer 1 (piezoelectric crystal). At the same time, the incident light wave emitted by the tunable laser of the communication band enters the device through the input photonic waveguide 32 and undergoes acousto-optic diffraction under the action of several acousto-optic deflection structure 3 units. After multiple deflection operations, the light is collected from any output port. The output light intensity is detected in real time by a photodetector and transmitted to an oscilloscope for waveform display and data recording. By analyzing the waveform changes in the oscilloscope, the acousto-optic modulation effect and frequency shift stability of the device can be directly verified.

[0034] Example 3 This embodiment is a third embodiment of an array-integrated switch frequency shifter chip based on acousto-optic deflection. This embodiment is similar to the first embodiment, except that in this embodiment, several acousto-optic deflection structures 3 provided in the first embodiment are combined in a preset arrangement to form a tunable acousto-optic frequency shifter.

[0035] like Figure 6 As shown, several acousto-optic deflection structures 3 are combined in series. The two output photonic waveguides 33 of the upper-level acousto-optic deflection structure 3 are connected to the downlink input photonic waveguide 32 of the lower-level acousto-optic deflection structure 3. An interdigital transducer 4 is provided around the acousto-optic deflection unit of each acousto-optic deflection structure 3. In this embodiment, the polarization control structure 34 is provided in the area below the acousto-optic deflection unit and above the acousto-optic deflection unit.

[0036] The working principle of the tunable acoustic-optical frequency shifter provided in this embodiment is as follows: like Figure 6As shown, when the light wave passes through the first acousto-optic deflection structure 3, the corresponding interdigital transducer 4 is activated, exciting surface acoustic waves on the surface of the lithium niobate thin film layer 1. The surface acoustic waves propagate through the high acousto-optic figure of merit material thin film layer 2, forming an acousto-optic grating in the two-dimensional acousto-optic deflection unit region. The light wave will generate a Doppler frequency shift and be deflected in the acousto-optic grating. The frequency-shifted light enters the uplink output port (i.e., the uplink output photonic waveguide 33) through the deflection and is input to the second acousto-optic deflection structure 3 connected to it. When the interdigital transducer 4 is disconnected, the light wave is not affected by the acoustic wave and maintains its original frequency through the downlink output port (i.e., the downlink output photonic waveguide 33) and enters the second photonic deflection structure. This process is repeated, and by selecting the input interdigital transducer 4, the output frequency shift can be adjusted.

[0037] This embodiment achieves a frequency-adjustable frequency shift function with high carrier suppression in single sideband by cascading multiple acousto-optic deflection structures 3. The frequency shift frequency is equal to the superposition of the input microwave frequencies of the connected interdigital transducers 4, mathematically expressed as Ω1 + Ω2 + ... + Ω N By selecting the on / off state of the input interdigital transducer 4, the frequency shift can be adjusted from MHz to GHz.

[0038] like Figure 7 The diagram shows a performance test link structure for the tunable acousto-optic frequency shifter described in this embodiment. This test system is used to accurately verify key performance indicators such as the frequency shift amount, frequency shift stability, and sideband suppression ratio of the device. Its core components include: a communication band tunable laser (used to provide monochromatic incident laser with a wavelength that can be finely adjusted around 1550 nm), a signal source (used to output a microwave electrical signal with an adjustable frequency as the driving signal for the interdigital transducer 4), a photodetector (used to convert the optical signal into an electrical signal to detect the frequency shift signal), a spectrum analyzer (used to perform spectrum analysis on the detected electrical signal to visually demonstrate the frequency shift effect), and two sets of optical couplers (used to realize beam splitting and beam combining of the optical path). The specific testing procedure of the testing system is as follows: During the testing phase, the tunable laser in the communication band is first activated. The incident laser output is split into two beams by the first set of optical couplers. The first beam is the "test light," which is input to the acousto-optic frequency shifter described in this embodiment and generates a preset frequency shift under the drive of the interdigital transducer 4. The second beam is the "reference light," which does not pass through any frequency shifting device and maintains its initial frequency. Subsequently, the "test light" and the "reference light" are combined through the second set of optical couplers to form the interference light signal required for heterodyne detection. After the interference light signal is input to the photodetector, the photodetector converts it into a corresponding electrical signal and transmits it to the spectrum analyzer. By analyzing the spectrum of the electrical signal through the spectrum analyzer, the frequency shift of the "test light" relative to the "reference light" can be directly identified, and the intensity, sideband distribution, and other information of the frequency shift signal can be clearly displayed on the spectrum analyzer, thereby completing the verification of the frequency shifting performance of the acousto-optic frequency shifter.

[0039] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0040] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. An array-integrated switch frequency shifter chip based on acousto-optic deflection, characterized in that, include: The lithium niobate thin film layer (1), the high acousto-optic figure of merit material thin film layer (2) disposed on the lithium niobate thin film layer (1) and heterogeneously integrated with the lithium niobate thin film, and the interdigital transducer (4) disposed on the lithium niobate thin film layer (1); the high acousto-optic figure of merit material thin film layer (2) is provided with an acousto-optic deflection structure (3), the acousto-optic deflection structure (3) includes a photon deflection unit (31), and an input photon waveguide (32) and an output photon waveguide (33) respectively connected to the photon deflection unit (31); a plurality of the acousto-optic deflection structures (3) are cascaded to realize a multi-channel array acousto-optic switch and / or tunable acousto-optic frequency shift; wherein, each photon deflection unit (31) is provided with at least one interdigital transducer (4).

2. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to claim 1, characterized in that, The material used in the high acoustic-optical figure of merit material thin film layer (2) includes antimony selenide or arsenic selenide.

3. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to claim 1, characterized in that, Each of the photonic deflection units (31) is configured with two input photonic waveguides (32) and two output photonic waveguides (33). Each of the input photonic waveguides (32) and the output photonic waveguides (33) integrates a polarization control structure (34) so ​​that the incident light and the outgoing light maintain their original polarization states. The width of the output photonic waveguide (33) is greater than the width of the input photonic waveguide (32) to form a non-reciprocal transmission characteristic.

4. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to claim 1, characterized in that, The photon deflection unit (31) is provided with a sawtooth-shaped surface acoustic wave absorption structure (35) for absorbing and scattering the remaining surface acoustic wave energy.

5. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to claim 1, characterized in that, The interdigital transducer (4) includes a plurality of interdigital electrodes, and there are structural differences among the plurality of interdigital electrodes.

6. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to any one of claims 1 to 5, characterized in that, The interdigital transducer (4) has a thickness of 80nm~200nm and can excite acoustic signals with a frequency difference of 200MHz~2GHz; the input photonic waveguide (32) and the output photonic waveguide (33) have a width of 300nm~30μm and a thickness of 200nm~500nm, and their working wavelengths are located in the communication band.

7. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to any one of claims 1 to 5, characterized in that, When used as an acousto-optic switch, the interdigital transducer (4) is located in the peripheral area of ​​the photon deflection unit (31). The excited surface acoustic wave diffracts the light entering the photon deflection unit (31). By adjusting the frequency of the acoustic wave and controlling the deflection angle, the optical power ratio of the output port can be adjusted by regulating the acoustic power.

8. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to claim 7, characterized in that, Several of the aforementioned acoustic-optic deflection structures (3) are combined according to preset requirements to form a switch array based on a cross-layer fully cross-interconnected network architecture to realize N×N multi-channel acoustic-optic switching and optical routing, where N is a positive integer greater than or equal to 2.

9. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to any one of claims 1 to 5, characterized in that, When used as an acousto-optic frequency shifter, the interdigital transducer (4) is located in the peripheral region of the photon deflection unit (31), and the excited surface acoustic wave generates a Doppler frequency shift on the light wave to achieve frequency shifting of the light wave.

10. The array-integrated switch frequency shifter chip based on acousto-optic deflection according to claim 9, characterized in that, Several of the aforementioned acousto-optic deflection structures (3) are combined in series to realize an acousto-optic frequency shifter with tunable output frequency, wherein the two output photonic waveguides (33) of the previous acousto-optic deflection structure (3) are simultaneously connected to the downlink input photonic waveguide (32) of the next adjacent acousto-optic deflection structure (3).

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