Spatial light manipulation method and device for phase-change photonic device

Abstract

The application provides a spatial light manipulation method and device of a phase-change photonic device, which comprises the following steps: determining a required pulse waveform, and generating pump light with the required pulse waveform; the pump light is irradiated onto the phase-change photonic device from above through a two-dimensional fiber array to manipulate the crystallization and amorphization states of the phase-change photonic device; test light is generated, the test light enters the phase-change photonic device through the two-dimensional fiber array and a grating coupler, is led out of the phase-change photonic device through the grating coupler and the two-dimensional fiber array, and the light signal led out is collected; and the light signal is converted into an electric signal and recorded. The method of introducing the manipulation light from outside the calculation array plane reduces the complexity of wiring in the array and reduces the loss caused by wiring in the optical path.

Description

Technical Field

[0001] This invention belongs to the field of micro-nano photonic device technology, and in particular to a spatial light manipulation method and apparatus for phase-change photonic devices. Background Technology

[0002] Photonic devices possess advantages such as high computational parallelism and high computational speed, and hold great promise for applications in logic computing and neuromorphic computing. Benefiting from the bosonic physics of photons, there is no interaction force between photons and almost no interference between them. Light of different wavelengths can be transmitted and communicated simultaneously in the optical path. At modulation frequencies of hundreds of gigahertz, photons can still achieve stable modulation and information transmission. Combined with the parallel potential of optical polarization and modes, ultra-high parallelism computing can be achieved.

[0003] The integration of phase change materials (PCMs) with photonic devices opens up broader prospects for reconfigurable integrated photonic computing. Currently, PCMs are based on chalcogenides, which can exhibit two states with different microstructural properties at room temperature: crystalline or amorphous. Thermal pulses generated electrically or optically can cause PCMs to switch states on a nanosecond timescale. Furthermore, the optical modes of PCMs are similar to those of nanophotonic waveguides, demonstrating excellent compatibility. This results in lower power consumption and improved energy efficiency in photonic devices, making them more suitable for non-volatile, reconfigurable neuromorphic computing.

[0004] The manipulation methods of phase-change photonic devices are mainly divided into two types: optical manipulation and electrical manipulation. Electrical manipulation mainly uses Joule heating generated by current to switch the device between crystallization and amorphization. However, since metallic materials strongly absorb computational light, it is generally necessary to use conductive materials with optical properties matching the waveguide mode to heat the device, which makes it impossible to achieve very low resistance and greatly limits the heating efficiency. Optical modulation usually modulates light through evanescent coupling, i.e., light confined in a waveguide. Compared with the external heater solution, it is more convenient and simpler, and has higher heating efficiency, enabling faster (~ns) device state switching. However, as the array size increases, the control wiring becomes more complex, which makes it difficult to further increase the computational density. Furthermore, on-chip optical modulation is highly dependent on the light absorption of the material. Therefore, it is usually difficult to achieve complete switching in this way for large-area (~μm) devices, because the light intensity attenuates along the device itself. When the light reaches the back end of the device, it may not carry enough energy to reach the phase transition threshold. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention proposes a spatial light manipulation method and apparatus for phase-change photonic devices.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0007] On one hand, this invention proposes a spatial light manipulation method for a phase-change photonic device, comprising:

[0008] Determine the desired pulse waveform and generate pump light with the desired pulse waveform;

[0009] Pump light is projected onto the phase-change photonic device from above through a two-dimensional fiber array, thereby manipulating the crystallization and amorphization states of the phase-change photonic device.

[0010] Test light is generated and enters the phase-change photonic device through a two-dimensional fiber array and a grating coupler. The test light is then led out of the phase-change photonic device through the grating coupler and the two-dimensional fiber array, and the led-out optical signal is collected. The optical signal is converted into an electrical signal and recorded.

[0011] On the other hand, the present invention proposes a spatial light manipulation device for a phase-change photonic device, comprising:

[0012] A pump laser source is used to generate pump light of the desired wavelength.

[0013] An electro-optic modulation control module is used to control the intensity of the pump light and the pulse waveform of the pump light to generate pump light with the desired pulse waveform.

[0014] A two-dimensional fiber array, through which pump light with the desired pulse waveform is irradiated from above onto a phase-change photonic device, thereby manipulating the crystallization and amorphization states of the phase-change photonic device.

[0015] A test laser source is used to generate test light of the required wavelength;

[0016] The test light enters the phase-change photonic device through a two-dimensional fiber array and a grating coupler, and is then led out of the phase-change photonic device through the grating coupler and the two-dimensional fiber array. The extracted light signal is incident on a photodetector, which converts the light signal into an electrical signal, which is then recorded by a data acquisition card.

[0017] Furthermore, the device of the present invention also includes a first adjustable attenuator and a first polarization controller. The test light output from the test laser source has its energy adjusted by the first adjustable attenuator and its polarization adjusted by the first polarization controller.

[0018] Furthermore, the device of the present invention also includes a first filter, which filters out noise of wavelengths other than the test light wavelength from the optical signal drawn from the two-dimensional fiber array before it is incident on the photodetector.

[0019] Furthermore, the device of the present invention also includes a second adjustable attenuator and a second polarization controller. The pump light output from the pump laser source has its energy adjusted by the second adjustable attenuator and its polarization adjusted by the second polarization controller.

[0020] Furthermore, the electro-optic modulation control module of the present invention includes an electro-optic intensity modulator, a signal generator, and a bias controller. The pump light is input to the electro-optic intensity modulator, which is jointly controlled by the bias controller and the signal generator. The bias controller controls the intensity of the pump light to the weakest intensity. The signal generator controls the waveform of the light pulse to generate a control pulse of arbitrary shape, so that the pump light output by the electro-optic intensity modulator is the pump light with the desired pulse waveform.

[0021] Furthermore, the device of the present invention also includes an amplifier for amplifying the power of the pump light output by the electro-optic intensity modulator.

[0022] Furthermore, the device of the present invention also includes a second filter, which is disposed in the optical path after the electro-optic modulation control module, for filtering out noise of other wavelengths besides the pump light wavelength. After being filtered by the second filter, the pump light with the required pulse waveform is irradiated from above through a two-dimensional fiber array to control the crystallization and amorphization states of the phase-change photonic device.

[0023] Compared with the prior art, the beneficial technical effects that this invention can produce are:

[0024] Pump light with the required pulse waveform can be generated according to the control needs, which facilitates state control;

[0025] The phase-change photonic device is heated and switched by top illumination with spatial light, which makes the state switching effect of the phase-change photonic device better and faster.

[0026] In this invention, the pump light serves as the control light. The intensity and pulse waveform of the pump light are adjustable, allowing for the adjustment of the intensity and pulse waveform of the pump light illuminating the phase-change photonic device as needed. This method of introducing control light from outside the computing array plane reduces the complexity of wiring in the array and lowers losses in the optical path caused by wiring.

[0027] The use of a two-dimensional fiber array scheme enables in-situ spatial optical manipulation of phase-change photonic devices, improving the accuracy and efficiency of device testing, and further realizing the state control of large device areas and multiple independent devices. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of a structure according to an embodiment of the present invention;

[0030] Figure 2 The following is a test result diagram of an embodiment of the present invention, wherein (a) is a diagram of the state manipulation effect of the phase change photonic device, and (b) is a diagram of the high-speed amorphization manipulation effect of the phase change photonic device.

[0031] Numbering on the map:

[0032] 1. Pump laser source; 2. Second adjustable attenuator; 3. Second polarization controller; 4. Signal generator; 5. Bias controller; 6. Electro-optic intensity modulator; 7. Amplifier; 8. Second filter; 9. Test laser source; 10. First adjustable attenuator; 11. First polarization controller; 12. Two-dimensional fiber array; 13. Grating coupler; 14. First filter; 15. Photodetector; 16. Data acquisition card; 17. Phase-change photonic device. Specific implementation methods

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the spirit of the disclosed content will be clearly explained below with reference to the accompanying drawings and detailed description. Any person skilled in the art, after understanding the embodiments of the present invention, can make changes and modifications based on the techniques taught in the present invention without departing from the spirit and scope of the present invention. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0034] On one hand, this invention proposes a spatial light manipulation method for a phase-change photonic device, comprising:

[0035] Determine the desired pulse waveform and generate pump light with the desired pulse waveform;

[0036] Pump light is projected onto the phase-change photonic device from above through a two-dimensional fiber array, thereby manipulating the crystallization and amorphization states of the phase-change photonic device.

[0037] Test light is generated and enters the phase-change photonic device through a two-dimensional fiber array and a grating coupler. The test light is then led out of the phase-change photonic device through the grating coupler and the two-dimensional fiber array, and the led-out optical signal is collected. The optical signal is converted into an electrical signal and recorded.

[0038] Based on the spatial light manipulation method of the phase-change photonic device provided in the above embodiments, refer to... Figure 1One embodiment provides a spatial light manipulation device for a phase-change photonic device capable of implementing the above-described method. In the figure, the dashed optical path between the pump laser source 1, the second adjustable attenuator 2, the second polarization controller 3, the electro-optic intensity modulator 6, the amplifier 7, the second filter 8, the two-dimensional fiber array 12, and the phase-change photonic device 17 represents the optical path of the pump light. The solid optical path between the test laser source 9, the first adjustable attenuator 10, the first polarization controller 11, the two-dimensional fiber array 12, the grating coupler 13, the phase-change photonic device 17, the first filter 14, and the photodetector 15 represents the optical path of the test light. Specifically, it includes:

[0039] Pump laser source 1, used to generate pump light of the desired wavelength;

[0040] An electro-optic modulation control module is used to control the intensity of the pump light and the pulse waveform of the pump light to generate pump light with the desired pulse waveform.

[0041] A two-dimensional fiber array 12, through which pump light with the desired pulse waveform is irradiated from above onto a phase-change photonic device 17, thereby manipulating the crystallization and amorphization states of the phase-change photonic device 17.

[0042] Test laser source 9 is used to generate test light of the required wavelength;

[0043] The test light enters the phase-change photonic device 17 through the two-dimensional fiber array 12 and the grating coupler 13, and is then led out of the phase-change photonic device 17 through the grating coupler 13 and the two-dimensional fiber array 12. The extracted light signal is incident on the photodetector 15, which converts the light signal into an electrical signal, and then records it through the data acquisition card 16.

[0044] Furthermore, the device in the above embodiments also includes a first adjustable attenuator 10 and a first polarization controller 11. The test light output by the test laser source 9 has its energy adjusted by the first adjustable attenuator 10 and its polarization adjusted by the first polarization controller 11.

[0045] Furthermore, the device in the above embodiment also includes a first filter 14, which filters out noise of wavelengths other than the test light wavelength from the optical signal drawn from the two-dimensional fiber array 12 before it is incident on the photodetector 15.

[0046] Furthermore, the device in the above embodiment also includes a second adjustable attenuator 2 and a second polarization controller 3. The pump light output by the pump laser source 1 has its energy adjusted by the second adjustable attenuator 2 and its polarization adjusted by the second polarization controller 3.

[0047] Furthermore, the electro-optic modulation control module in the above embodiment includes an electro-optic intensity modulator 6, a signal generator 4, and a bias controller 5. The pump light is input to the electro-optic intensity modulator 6, which is jointly controlled by the bias controller 5 and the signal generator 4. The bias controller 5 controls the intensity of the pump light to the weakest intensity. The signal generator 4 controls the waveform of the light pulse to generate a control pulse of arbitrary shape, so that the pump light output by the electro-optic intensity modulator 6 is the pump light with the desired pulse waveform.

[0048] Furthermore, the device in the above embodiment also includes an amplifier 7 for amplifying the power of the pump light output by the electro-optic intensity modulator 6. It also includes a second filter 8, disposed in the optical path after the electro-optic modulation control module. In this embodiment, the second filter 8 is disposed after the amplifier 7 to filter out noise of wavelengths other than the pump light wavelength. After being filtered by the second filter 8, the pump light with the desired pulse waveform is emitted from above through the two-dimensional fiber array 12 and irradiates the phase-change photonic device 17, thereby manipulating the crystallization and amorphization states of the phase-change photonic device 17.

[0049] In one embodiment of the present invention, the following is employed: Figure 1 The spatial light manipulation device for the phase-change photonic device shown uses a 1560nm laser as the test laser source and a 1550nm laser as the pump source. The phase-change photonic device is made of Ge2Sb2Te5 with a material thickness of 30nm. One phase-change photonic device is manipulated. The final test results are shown in the figure below. Figure 2 As shown, the collected data represent the state changes of phase-change photonic devices. Figure 2 As shown in (a), the phase-change photonic device of the present invention has a large state control range, capable of being controlled almost from zero transmittance. The state optical contrast of the present invention can exceed 25 times (14 dB), and a large number of phase-change photonic devices can be controlled. Figure 2 As shown in (b), the phase-change photonic device of the present invention requires a short amorphization time; currently, this scheme has verified efficient amorphization at 4 ns. The present invention can be used to achieve independent manipulation of multi-phase-change photonic devices, which is expected to further increase optical contrast and the number of states.

[0050] Matters not covered in this invention are common knowledge.

[0051] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0052] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A spatial light manipulation device for phase-change photonic devices, characterized in that, include: A pump laser source is used to generate pump light of the desired wavelength. An electro-optic modulation control module is used to control the intensity of the pump light and the pulse waveform of the pump light to generate pump light with the desired pulse waveform. The electro-optic modulation control module includes an electro-optic intensity modulator, a signal generator, and a bias controller. The pump light is input to the electro-optic intensity modulator, which is jointly controlled by the bias controller and the signal generator. The bias controller controls the intensity of the pump light to the weakest intensity. The signal generator controls the waveform of the light pulse to generate a control pulse of arbitrary shape, so that the pump light output by the electro-optic intensity modulator is the pump light with the desired pulse waveform. A two-dimensional fiber array, through which pump light with the desired pulse waveform is irradiated from above onto a phase-change photonic device, thereby manipulating the crystallization and amorphization states of the phase-change photonic device. A test laser source is used to generate test light of the required wavelength; The test light enters the phase-change photonic device through a two-dimensional fiber array and a grating coupler, and is then led out of the phase-change photonic device through the grating coupler and the two-dimensional fiber array. The extracted light signal is incident on a photodetector, which converts the light signal into an electrical signal, which is then recorded by a data acquisition card.

2. The spatial light manipulation device for a phase-change photonic device according to claim 1, characterized in that, The pump light has a wavelength of 1550 nm, and the test light has a wavelength of 1560 nm.

3. The spatial light manipulation device for a phase-change photonic device according to claim 1 or 2, characterized in that, It also includes a first adjustable attenuator and a first polarization controller. The test light output from the test laser source has its energy adjusted by the first adjustable attenuator and its polarization adjusted by the first polarization controller.

4. The spatial light manipulation device for a phase-change photonic device according to claim 3, characterized in that, It also includes a first filter, which filters out noise of wavelengths other than the test light wavelength from the optical signal drawn from the two-dimensional fiber array before it is incident on the photodetector.

5. The spatial light manipulation device for a phase-change photonic device according to claim 1, 2, or 4, characterized in that, It also includes a second adjustable attenuator and a second polarization controller. The pump light output from the pump laser source has its energy adjusted by the second adjustable attenuator and its polarization adjusted by the second polarization controller.

6. The spatial light manipulation device for a phase-change photonic device according to claim 5, characterized in that, It also includes an amplifier for amplifying the power of the pump light output from the electro-optic intensity modulator.

7. The spatial light manipulation device for a phase-change photonic device according to claim 5, characterized in that, It also includes a second filter, which is set in the optical path after the electro-optic modulation control module to filter out noise of other wavelengths besides the pump light wavelength. After being filtered by the second filter, the pump light with the required pulse waveform is irradiated from above through the two-dimensional fiber array to control the crystallization and amorphization states of the phase-change photonic device.

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