Use of a photodetector in a logic circuit

Abstract

The application discloses an application of a photoelectric detector in a logic circuit, and the photoelectric detector adopts a sandwich structure formed by upper and lower electrode layers and a semiconductor layer, wherein the upper and lower electrode layers form Schottky contact or ohmic contact with the semiconductor layer respectively, and do not form ohmic contact at the same time. By adjusting an applied bias voltage, an incident light wavelength and power, reversible conversion of a photocurrent from a hot electron dominated positive response to a hot hole dominated negative response can be realized, and a tunable bipolar light response characteristic is obtained. Based on the mechanism, six basic logic functions of "OR", "XOR", "AND", "NAND", "NOR" and "NOT" are realized, and an integrated photoelectric logic gate circuit is constructed. Compared with a traditional electronic transistor logic circuit, the application has the advantages of simple structure, low power consumption, high integration and good process compatibility, and provides a new implementation approach for development of a low-cost semiconductor photoelectric logic chip and on-chip optical computing.

Description

Technical Field

[0001] This invention relates to the field of photodetector technology, and more specifically to the application of a photodetector in logic circuits. Background Technology

[0002] With the development of social informatization, the total amount of global data is growing exponentially. Traditional electronic logic gates are gradually encountering performance bottlenecks in scenarios such as large-scale parallel computing, optical communication, and artificial intelligence. Electronic logic gates, with transistors at their core, use high and low voltage levels to represent logical states and implement basic logical operations such as "AND," "OR," and "NAND." However, electronic devices suffer from high power consumption, significant thermal effects, and severe signal crosstalk, making it difficult to simultaneously achieve high-speed computing and low-power operation. To overcome this bottleneck, optoelectronic logic gates (OELGs) have become a highly anticipated solution. OELGs utilize optical signals as inputs and electrical signals as outputs, enabling photoelectric conversion and logical operations within the same device. They offer advantages such as high-speed response, low power consumption, and no crosstalk. Furthermore, they can implement multiple logic functions within a single photodetector, greatly improving device integration and system processing efficiency, making them a key direction for building next-generation on-chip optical computing and intelligent vision chips.

[0003] In recent years, photodetectors with bipolar photoresponse have provided new ideas for realizing the integration of multiple logic functions. The core lies in achieving positive and negative switching of the photocurrent direction by controlling the wavelength, intensity, or external electric field of light, thereby executing multiple logic operations in a single device. For example, Hu Weida's team reported on-chip optoelectronic logic gates based on black phosphorus / silicon waveguide structures in Nature Photonics (2024). This device, by controlling the spatial distribution and intensity of incident light in different waveguides, performs multiple logic operations, including "AND", "OR", "NAND", "NOR", "XOR", and "XNOR," on a single chip, demonstrating the programmable potential of two-dimensional materials on silicon photonics platforms. Yusin Pak et al. reported in Nature Communications (2022) that by relying on defect state manipulation and ion migration effects in perovskite layers, light-induced bipolar photocurrent reversal was achieved; by adjusting the incident light of different wavelengths, multiple logic operations can be performed in a single detector. In addition, Zhangming Zhu's team designed a MoS2 / Ge heterojunction field-effect phototransistor in Advanced Science (2024), realizing positive and negative photocurrents that can be switched with wavelength. By adjusting the light intensity and the power density of the input signal, they implemented logic gate operations such as "AND", "OR", "NAND", "NOT", and "NOR" on a single device.

[0004] While the aforementioned studies demonstrate that photodetectors based on two-dimensional materials and perovskites can achieve multiple logic functions, significant limitations remain. Firstly, such material systems struggle to achieve highly consistent large-scale device array fabrication and integration. Secondly, some two-dimensional and perovskite materials are sensitive to environmental factors (such as humidity, oxygen, or light), and their long-term operational stability and repeatability require further improvement. These factors collectively limit their application and widespread adoption in practical on-chip optoelectronic logic chips. In contrast, semiconductor photodetectors offer significant advantages in process compatibility, environmental stability, cost control, and large-scale array fabrication, making them an ideal platform for on-chip optoelectronic logic integration. However, traditional semiconductor photodetectors typically exhibit only unipolar photocurrents, hindering the integration of multiple logic functions. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention aims to provide an application of a photodetector in logic circuits. This photodetector is a silicon-based photodetector with tunable bipolar photoresponse characteristics. By adjusting the bias voltage, incident light wavelength, and power, the direction of the photocurrent can be switched from positive to negative, thereby integrating multiple logic functions in a single device. This invention utilizes a semiconductor photodetector to achieve positive and negative bipolar photocurrents in the short-wave infrared band. Based on this bipolar response characteristic, the constructed semiconductor optoelectronic logic gates can implement six basic logic operations: "OR", "XOR", "AND", "NAND", "NOR", and "NOT". This invention overcomes the inherent limitation of unidirectional photoresponse in semiconductor materials, providing a new technical approach for constructing low-power, high-stability, and arrayable optoelectronic logic systems.

[0006] The above-mentioned objective of the present invention is achieved through the following technical solution:

[0007] An application of a photodetector in a logic circuit, wherein the photodetector is used in a photoelectric logic gate to realize OR, XOR, AND, NAND, NOR, and NOT logic functions;

[0008] The photodetector includes a bottom electrode layer, a semiconductor layer, and a top electrode layer stacked sequentially.

[0009] The bottom electrode layer forms a Schottky contact with the semiconductor layer, and the top electrode layer forms a Schottky contact with the semiconductor layer; or, the bottom electrode layer forms a Schottky contact with the semiconductor layer, and the top electrode layer forms an ohmic contact with the semiconductor layer; or, the bottom electrode layer forms an ohmic contact with the semiconductor layer, and the top electrode layer forms a Schottky contact with the semiconductor layer.

[0010] The photodetector based on a planar multilayer structure of semiconductor nanofilm provided by this invention exhibits broadband response characteristics in the short-wave infrared band and can achieve bipolar photoresponse detection under a small bias voltage (< 0.15 V), with its photocurrent direction continuously tunable in the short-wave infrared band. This characteristic stems from the nanoscale thickness of the semiconductor layer; by changing the bias voltage, incident light wavelength, and power, the photoresponse can be switched from positive to negative photocurrent. Based on this, the photodetector can demonstrate the implementation of six representative logic operations—OR, XOR, AND, NAND, NOR, and NOT—using only a single device without changing the external circuitry, showcasing the application potential of integrated optoelectronic logic gates.

[0011] Furthermore, the material of the bottom electrode layer is selected from gold (Au), silver (Ag), titanium (Ti), copper (Cu), chromium (Cr), aluminum (Al), alloys containing at least two of the following metallic elements: gold (Au), silver (Ag), titanium (Ti), copper (Cu), chromium (Cr), and aluminum (Al), titanium nitride (TiN), titanium dioxide (TiO2), tin dioxide (SnO2), zinc oxide (ZnO), molybdenum trioxide (MoO3), tungsten trioxide (WO3), and nickel oxide (NiO). x Vanadium pentoxide (V2O5), poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), poly(3-hexylthiophene-2,5-diyl) (P3HT), 2,2',7,7'-tetratetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene (Spiro-OMeTAD), methyl [6,6]-phenyl-C61-butyrate (PCBM), fullerene (C 60 One or more of poly(ethylene imine ethoxylate) (PEIE) and 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi).

[0012] Furthermore, the thickness of the bottom electrode layer is greater than 30 nm, for example, it can be 50 nm, 100 nm, 500 nm, 1 μm, or a range of any two values.

[0013] Preferably, the bottom electrode layer is a bottom metal film layer, and the material of the bottom metal film layer is selected from one or more of Au, Ag, Ti, Cu, Cr, Al and alloys containing at least two metal elements selected from Au, Ag, Ti, Cu, Cr, Al.

[0014] Furthermore, the resistivity of the semiconductor layer is 1-100 Ω·cm.

[0015] Furthermore, the thickness of the semiconductor layer is 5 nm-10 μm, preferably 5 nm-100 nm, such as 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, etc., including but not limited to the thickness values ​​listed above, and may also be other thickness values ​​within the above range.

[0016] Furthermore, the material of the semiconductor layer is selected from one or more of silicon (Si), germanium (Ge), gallium arsenide (GaAs), indium phosphide (InP), gallium nitride (GaN), and indium gallium arsenide (InGaAs).

[0017] Preferably, the semiconductor layer is a silicon film layer, and the material of the silicon film layer is lightly doped n-type single crystal silicon or lightly doped p-type single crystal silicon.

[0018] Furthermore, the material of the top electrode layer is selected from gold (Au), silver (Ag), titanium (Ti), copper (Cu), chromium (Cr), aluminum (Al), alloys containing at least two of the metal elements selected from gold, silver, titanium, copper, chromium, and aluminum, titanium nitride (TiN), titanium dioxide (TiO2), tin dioxide (SnO2), zinc oxide (ZnO), molybdenum trioxide (MoO3), tungsten trioxide (WO3), and nickel oxide (NiO). x Vanadium pentoxide (V2O5), poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), poly(3-hexylthiophene-2,5-diyl) (P3HT), 2,2',7,7'-tetratetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene (Spiro-OMeTAD), methyl [6,6]-phenyl-C61-butyrate (PCBM), fullerene (C 60 One or more of poly(ethylene imine ethoxylate) (PEIE) and 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi).

[0019] Furthermore, the thickness of the top electrode layer is 10 nm to 1 μm, for example, it can be 10 nm, 20 nm, 50 nm, 100 nm, 500 nm, 1 μm, or a range of any two values.

[0020] Preferably, the top electrode layer is a top metal film layer, and the material of the top metal film layer is selected from one or more of Au, Ag, Ti, Cu, Cr, Al and alloys containing at least two metal elements selected from Au, Ag, Ti, Cu, Cr, Al.

[0021] Preferably, the material of the bottom electrode layer is different from the material of the top electrode layer.

[0022] In a specific embodiment, the photodetector of the present invention employs a planar structure with a silicon nanofilm sandwiched between upper and lower metal electrodes. The Schottky barrier formed between the bottom metal layer and the silicon nanofilm is relatively small, while the Schottky barrier formed between the top metal layer and the silicon nanofilm is relatively large. Without an external bias voltage, the net electric field in the silicon nanofilm points from the bottom metal to the top metal. The thermionic electrons generated after the bottom metal absorbs incident light migrate upwards under the drive of the built-in electric field and are collected by the top metal, forming a forward photocurrent. As a forward bias voltage is applied to the bottom metal layer, the net electric field in the silicon nanofilm gradually weakens, and the photocurrent dominated by the thermionic electrons generated by the bottom metal's light absorption decreases. Simultaneously, the thermionic holes generated by the bottom metal's light absorption are gradually collected under the action of the external electric field, causing the net photocurrent to decrease with increasing bias voltage. As the applied bias voltage increases further, the transport contributions of electrons and holes cancel each other out, and the net photocurrent drops to zero. With further increases in bias voltage, the process of hot holes being collected by the top metal becomes dominant, reversing the polarity of the photocurrent and resulting in a negative photocurrent. Furthermore, the amplitude of the negative photocurrent increases further with increasing bias voltage. By adjusting the bias voltage, a dynamic switching from hot electrons to hot holes can be achieved, enabling the device to exhibit a tunable bipolar photoresponse in the short-wave infrared band. This characteristic provides the physical basis for integrating multiple logic functions such as "OR", "XOR", "AND", "NAND", "NOR", and "NOT" into a single silicon-based photodetector.

[0023] Furthermore, an antireflection layer is provided on the side of the top electrode layer away from the semiconductor layer, and the antireflection layer is made of polymethyl methacrylate (PMMA).

[0024] Furthermore, the thickness of the antireflection layer is 50-300 nm.

[0025] In a specific embodiment, the method for fabricating the photodetector includes the following steps:

[0026] The silicon on the pretreated insulating layer is placed in a hydrofluoric acid solution to remove the insulating layer and obtain the silicon film layer.

[0027] Top electrode layers and bottom electrode layers are prepared on the upper and lower surfaces of the silicon film using physical and / or chemical methods, respectively.

[0028] Furthermore, the pretreatment includes a process of ultrasonically cleaning the silicon on the insulating layer sequentially with organic solvent and water.

[0029] Furthermore, the insulating layer is a silicon dioxide layer.

[0030] Furthermore, the physical and / or chemical methods include magnetron sputtering deposition and electron beam evaporation.

[0031] Based on the bipolar photocurrent characteristics of photodetectors, this invention designs a photoelectric logic gate system that realizes six basic logic functions: OR, XOR, AND, NAND, NOR, and NOT by changing the bias voltage and the wavelength and intensity of the modulated light.

[0032] Furthermore, two short-wave infrared beams of different wavelengths are used as incident light inputs. The input states of the incident light include logic "0" and "1", which correspond to "no illumination" and "illumination" of the incident light, respectively. The wavelengths of the two short-wave infrared beams are in the range of 1.1 μm to 2.0 μm.

[0033] By adjusting the bias voltage applied to the photodetector, the photocurrent response of the photodetector to the incident light input changes;

[0034] A preset current range is defined as the logic "0" output, and the area outside the preset current range is defined as the logic "1" output, realizing the dynamic switching of OR, XOR, and NOT logic functions.

[0035] The wavelength of the incident light, the bias voltage of the photodetector, and the preset current range can be adaptively adjusted according to actual usage requirements.

[0036] In a specific embodiment, the wavelengths of the two short-wave infrared beams are 1.3 μm and 1.6 μm, respectively, and the preset current range is -2 μA to 0.25 μA.

[0037] Furthermore, the power of both short-wave infrared beams is 4-6 mW.

[0038] In a specific embodiment, the power of the 1.3 μm shortwave infrared light is 4.16 mW, and the power of the 1.6 μm shortwave infrared light is 4.32 mW.

[0039] Furthermore, when implementing the OR logic function, the bias voltage applied to the photodetector is 10 mV; when implementing the XOR logic function, the bias voltage applied to the photodetector is 20 mV; when implementing the NOT logic function, the bias voltage applied to the photodetector is 20 mV.

[0040] Furthermore, when neither 1.3 μm nor 1.6 μm shortwave infrared light is irradiated, the input state of the incident light is logic "00"; when only 1.3 μm shortwave infrared light is irradiated, the input state of the incident light is logic "10"; when only 1.6 μm shortwave infrared light is irradiated, the input state of the incident light is logic "01"; and when both 1.3 μm and 1.6 μm shortwave infrared light are irradiated simultaneously, the input state of the incident light is logic "11".

[0041] Furthermore, when implementing the OR logic function, when the input state of the incident light is logic "10", "01", or "11", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00", the output of the photodetector is logic "0".

[0042] Furthermore, when implementing the XOR logic function, when the input state of the incident light is logic "10" or "01", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00" or "11", the output of the photodetector is logic "0".

[0043] Furthermore, when implementing the NOT logic function, an output logic "1" indicates that 1.6 μm short-wave infrared light is not irradiated, and an output logic "0" indicates that 1.6 μm short-wave infrared light is irradiated; when the input state of the incident light is logic "10", the output of the photodetector is logic "1"; when the input state of the incident light is logic "11", the output of the photodetector is logic "0".

[0044] Furthermore, two short-wave infrared beams are used as incident light, and the input states of the incident light include logic "0" and "1", which correspond to "no illumination" and "illumination" of the incident light, respectively.

[0045] A beam of short-wave infrared light is used as the modulation light, and the modulation light satisfies the following: the direction of the photocurrent generated by turning on the modulation light alone is opposite to the direction of the photocurrent generated by turning on the incident light alone.

[0046] By adjusting the power of the modulated light, the photocurrent response of the photodetector to the incident light input changes;

[0047] A preset current range is defined as the logic "0" output, and the area outside the preset current range is defined as the logic "1" output, realizing the dynamic switching of OR, XOR, AND, NAND, NOR and NOT logic functions.

[0048] The wavelength of the incident light, the power of the incident light, the wavelength of the modulated light, the power of the modulated light, and the preset current range can be adaptively adjusted according to actual usage requirements.

[0049] In a specific implementation, 1.6 μm or 1.4 μm short-wave infrared light is used as the modulation light, and the preset current range is -2 μA to 0.25 μA.

[0050] Furthermore, OR, XOR, and AND logic functions are implemented when modulated with 1.6 μm short-wave infrared light.

[0051] Furthermore, the power of the 1.6 μm shortwave infrared light is 90 μW-4 mW.

[0052] Furthermore, when implementing the OR logic function, the power of the 1.6 μm short-wave infrared light is 93.19 μW; when implementing the XOR logic function, the power of the 1.6 μm short-wave infrared light is 1.31 mW; and when implementing the AND logic function, the power of the 1.6 μm short-wave infrared light is 3.10 mW.

[0053] Furthermore, when using 1.6 μm short-wave infrared light as the modulation light, the incident light consists of 1.2 μm short-wave infrared light and 1.3 μm short-wave infrared light.

[0054] Furthermore, the power of the incident light is 3-6 mW.

[0055] In a specific embodiment, the power of the 1.2 μm shortwave infrared light is 3.39 mW, and the power of the 1.3 μm shortwave infrared light is 4.16 mW.

[0056] Furthermore, when neither 1.2 μm nor 1.3 μm shortwave infrared light is irradiated, the input state of the incident light is logic "00"; when only 1.2 μm shortwave infrared light is irradiated, the input state of the incident light is logic "10"; when only 1.3 μm shortwave infrared light is irradiated, the input state of the incident light is logic "01"; and when both 1.2 μm and 1.3 μm shortwave infrared light are irradiated simultaneously, the input state of the incident light is logic "11".

[0057] Furthermore, when implementing the OR logic function, when the input state of the incident light is logic "10", "01", or "11", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00", the output of the photodetector is logic "0".

[0058] Furthermore, when implementing the XOR logic function, when the input state of the incident light is logic "10" or "01", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00" or "11", the output of the photodetector is logic "0".

[0059] Furthermore, when implementing the AND logic function, when the input state of the incident light is logic "11", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00", "10", or "01", the output of the photodetector is logic "0".

[0060] Furthermore, NAND, NOR, and NOT logic functions are implemented when modulated with 1.4 μm short-wave infrared light.

[0061] Furthermore, the power of the 1.4 μm shortwave infrared light is 3-6 mW.

[0062] Furthermore, when implementing NAND logic functions, the power of the 1.4 μm short-wave infrared light is 3.07 mW; when implementing NOR logic functions, the power of the 1.4 μm short-wave infrared light is 3.77 mW; and when implementing NOT logic functions, the power of the 1.4 μm short-wave infrared light is 3.77 mW.

[0063] Furthermore, when using 1.4 μm shortwave infrared light as the modulation light, the incident light consists of 1.6 μm shortwave infrared light and 1.7 μm shortwave infrared light.

[0064] Furthermore, the power of the incident light is 0.3-0.4 mW.

[0065] In a specific embodiment, the power of the 1.6 μm shortwave infrared light is 0.37 mW, and the power of the 1.7 μm shortwave infrared light is 0.31 mW.

[0066] Furthermore, when neither 1.6 μm nor 1.7 μm shortwave infrared light is irradiated, the input state of the incident light is logic "00"; when only 1.6 μm shortwave infrared light is irradiated, the input state of the incident light is logic "10"; when only 1.7 μm shortwave infrared light is irradiated, the input state of the incident light is logic "01"; and when both 1.6 μm and 1.7 μm shortwave infrared light are irradiated simultaneously, the input state of the incident light is logic "11".

[0067] Furthermore, when implementing NAND logic functions, when the input state of the incident light is logic "00", "10", or "01", the output of the photodetector is logic "1"; when the input state of the incident light is logic "11", the output of the photodetector is logic "0".

[0068] Furthermore, when implementing the NOR logic function, when the input state of the incident light is logic "00", the output of the photodetector is logic "1"; when the input state of the incident light is logic "10", "01", or "11", the output of the photodetector is logic "0".

[0069] Furthermore, when implementing the NOT logic function, when the input state of the incident light is logic "00", the output of the photodetector is logic "1"; when the input state of the incident light is logic "10" or "01", the output of the photodetector is logic "0". Specifically, an output logic "1" indicates simultaneous illumination by 1.6 μm and 1.7 μm short-wave infrared light, while an output logic "0" indicates that 1.6 μm and 1.7 μm short-wave infrared light are not simultaneously illuminating the light.

[0070] The beneficial effects of this invention are:

[0071] 1. This invention provides a planar multilayer photodetector based on a semiconductor thin film. Its core characteristic is that the direction of photocurrent can be dynamically tunable within the 1100 nm to 2000 nm wavelength band by adjusting the bias voltage, incident light wavelength, and power. Based on this characteristic, this invention successfully designed and implemented six basic logic gate circuits, wherein the determination of logic outputs "1" and "0" is uniformly based on a current range of -2 μA to 0.25 μA (this range is logic "0", and outside the range is logic "1").

[0072] 2. The photodetector provided by this invention adopts a semiconductor-based structure, possessing good compatibility with existing integrated circuit processes, facilitating integration and large-scale fabrication, and significantly improving the operational reliability of logic gates. By combining multiple logic functional units, it can be extended to realize more complex data processing tasks (such as arithmetic addition and subtraction, counting, etc.). Compared with traditional logic circuits based on electronic transistors, this invention exhibits significant advantages in space utilization and cost control, and is expected to find widespread application in future optical computing, optical communication, and other fields. Attached Figure Description

[0073] Figure 1 This is a schematic diagram of the photodetector in Example 1.

[0074] Figure 2 The diagram shows the energy band structure of the photodetector in Example 1 under different bias voltages; where (a) is 0 bias voltage, (b) is low bias voltage (60 mV), and (c) is high bias voltage (140 mV).

[0075] Figure 3The graph shows the photocurrent-time (IT) curves of the photodetector of Example 1 under different bias voltages and short-wave infrared light irradiation at different wavelengths. The wavelengths from left to right range from 1.1 μm to 2 μm, with an interval of 50 nm. Among them, (a) is the result under a bias voltage of 0 mV, (b) is the result under a bias voltage of 60 mV, and (c) is the result under a bias voltage of 140 mV.

[0076] Figure 4 The following are the photoelectric characteristics of the photodetector in Example 1: (a) shows the relationship between photocurrent and incident light power under different bias voltages at a wavelength of 1.6 μm illumination. The bias voltage gradually increases from 0 mV to 100 mV, with the arrow indicating the direction of voltage increase and the gray dashed line indicating that the photocurrent is equal to 0; (b) shows the IT curve under a wavelength of 1.6 μm illumination, where "on" indicates the light is on and "off" indicates the light is off, the incident light power is 4.32 mW, the arrow indicates the direction of voltage increase, and the bias voltage is the same color as that represented in (a); (c) shows the relationship between photocurrent and incident light power at a bias voltage of 50 mV, with the two curves representing the test order from small to large and from large to small incident light power, respectively; (d) shows the relationship between incident light power and photocurrent at different wavelengths at a bias voltage of 0 mV; (e) shows the relationship between incident light power and photocurrent at different wavelengths at a bias voltage of 50 mV; (f) shows the relationship between 140... The graphs (d), (e), and (f) show the relationship between incident light power and photocurrent at different wavelengths under a bias voltage of mV. The colors representing the bias voltage are consistent.

[0077] Figure 5 The graph shows the relationship between the photocurrent and bias voltage of the photodetector in Example 1; where (a) is a graph showing the change of photocurrent with wavelength and bias voltage; (b) is a graph showing the change of photocurrent with incident wavelength under different bias voltages, where the arrow indicates the direction of increasing bias voltage and the gray dashed line indicates that the photocurrent is equal to 0; (c) is a graph showing the change of photocurrent with bias voltage under different wavelength illumination, where the arrow indicates the increase of wavelength and the gray dashed line indicates that the photocurrent is equal to 0.

[0078] Figure 6 The following are the photoelectric characteristics of the photodetector in Example 2: (a) is the IT curve under different bias voltages with 1.55 μm illumination and 3.7 mW power; (b) is the photocurrent spectrum in the 1.2-1.8 μm band under different bias voltages with 1.55 μm illumination and 3 mW power; (c) is the relationship between photocurrent and incident light power with 1.55 μm illumination and 40 mV bias voltage; and (d) is the relationship between photocurrent and incident light power with different bias voltages with 1.55 μm illumination and 3.7 mW power.

[0079] Figure 7The graphs show the relationship between the photocurrent of the photodetector in Example 2 and the bias voltage, incident light wavelength, and power. Specifically, (a) shows the photocurrent variation with wavelength and bias voltage at an incident light power of 3 mW; (b) shows the photocurrent variation with bias voltage at different wavelengths under an incident light power of 3 mW, with arrows indicating the direction of increasing wavelength and red dashed lines indicating zero photocurrent; (c) shows the wavelength variation with bias voltage when the photocurrent is zero at an incident light power of 3 mW; (d) shows the photocurrent variation with bias voltage and power under 1.55 μm illumination; (e) shows the photocurrent variation with bias voltage under 1.55 μm illumination and different powers; (f) shows the power variation with bias voltage when the photocurrent is zero under 1.55 μm illumination; (g) shows the photocurrent variation with wavelength and power at a bias voltage of 60 mV; (h) shows the photocurrent variation with power at different wavelengths under a bias voltage of 60 mV; and (i) shows the photocurrent variation with bias voltage of 60 mV. The graph shows the change in wavelength as a function of power when the photocurrent is 0 at a voltage of mV.

[0080] Figure 8 The diagram below illustrates the implementation of OR, XOR, and NOT logic functions in the photodetector of Example 1. (a) is a schematic diagram of the application of logic gates "OR", "XOR", and "NOT"; (b) is the truth table of the logic gates; (c) is a schematic diagram of the logic gate transition by changing the bias voltage, where "10" indicates only 1.3 μm light input, "01" indicates only 1.6 μm light input, and "11" indicates simultaneous input of 1.3 μm and 1.6 μm light; (d) is the IT curve of logic gate "OR" implemented with a modulation bias voltage of 10 mV; (e) is the IT curve of logic gate "XOR" implemented with a modulation bias voltage of 20 mV; and (f) is the IT curve of logic gate "NOT" implemented with a modulation bias voltage of 20 mV.

[0081] Figure 9The diagram illustrates the implementation of OR, XOR, AND, NAND, NOR, and NOT logic functions by the photodetector in Example 1. (a) is a schematic diagram of the logic gates "OR", "XOR", "AND", "NAND", "NOR", and "NOT"; (b) is the truth table of the logic gates; (c) is a schematic diagram illustrating the logic gate transitions when the optical power of the modulated light (1.6 μm) is changed, where "10" indicates only 1.2 μm light input, "01" indicates only 1.3 μm light input, and "11" indicates simultaneous input of 1.2 μm and 1.3 μm light; (d) is an IT curve diagram illustrating the implementation of logic gates "OR", "XOR", and "AND" when the modulated light power is 93.19 μW, 1.31 mW, and 3.10 mW respectively; (e) is a schematic diagram illustrating the logic gate transitions when the optical power of the modulated light (1.4 μm) is changed, where "10" indicates only 1.6 μm light input, "01" indicates only 1.7 μm light input, and "11" indicates simultaneous input of 1.6 μm and 1.7 μm light. (f) shows the IT curves for implementing logic gates “NAND”, “NOR”, and “NOT” when the modulation optical power is 3.07 mW, 3.77 mW, and 3.77 mW, respectively. Detailed Implementation

[0082] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0083] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0084] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are commercially available.

[0085] In the embodiments described below, short-wave infrared light was focused using a Mitutoyo objective lens (10×, 0.26 NA), and the optical power was measured using a calibrated integrating sphere photodiode power sensor (extended InGaAs) (Thorlabs, S148C). Photocurrent was recorded using a Keysight B1500A semiconductor device parameter analyzer.

[0086] Example 1

[0087] A photodetector (Si NM-HCPD) with the following structure Figure 1 As shown, from bottom to top, it includes:

[0088] Bottom metal film (Al): 70 nm thick aluminum film;

[0089] Silicon film (p-Si): 100 nm thick;

[0090] Top metal film (Ti): 20 nm thick titanium film.

[0091] The fabrication method of the above photodetector includes the following steps:

[0092] (1) A commercial silicon-on-insulator (SOI) substrate that has been ultrasonically cleaned with acetone, ethanol and deionized water is placed in a 40% hydrofluoric acid solution. After removing the silicon oxide layer, a 100 nm thick lightly doped p-type silicon film (p-Si) with a resistivity of 10 Ω·cm is obtained suspended in the solution.

[0093] (2) A silicon film layer was retrieved using a silicon oxide wafer with photoresist spin-coated on it. After drying, a 70 nm thick aluminum film layer was deposited using magnetron sputtering technology (pre-sputtering was performed for 5 min before film deposition, and the deposition vacuum degree was 5 × 10⁻⁶). -4 The parameters for magnetron sputtering include: an aluminum target, a power of 50 W, argon gas introduced during sputtering, and an internal pressure of 1 Pa. The sputtered film is then transferred to acetone and allowed to stand to obtain a Si-Al composite film suspended in an organic solvent.

[0094] (3) A Si-Al composite film was retrieved using a silicon oxide wafer sputtered with gold, with the silicon film facing upwards. A 200 μm × 200 μm window was exposed using ultraviolet lithography. Then, a 20 nm thick titanium film was deposited using electron beam evaporation (pre-sputtering was performed for 5 min before film deposition; the parameters for electron beam evaporation included: titanium-gold particles as the evaporating material, an evaporation rate of 0.5 A / s, and a working vacuum of 5 e). -4 The device was then immersed in acetone solution (with a working temperature of 20 °C), left to stand for a period of time, and then removed and air-dried to prepare a photodetector (Si NM-HCPD) with an effective area of ​​200 μm × 200 μm.

[0095] Figure 1 China V FThe bias voltage is set such that the aluminum film voltage is higher than or equal to the titanium film voltage, and short-wave infrared light is incident perpendicularly onto the photodetector surface. The Schottky barrier formed by the bottom metal film and the silicon nanofilm is relatively small, while the Schottky barrier formed by the top metal film and the silicon nanofilm is relatively large. Without an applied bias voltage, the net electric field in the silicon film points from the bottom metal to the top metal. The thermionic electrons generated after the bottom metal absorbs the incident light migrate upwards under the drive of the built-in electric field and are collected by the top metal, forming a positive photocurrent. Therefore, the net photocurrent under zero bias conditions is mainly contributed by thermionic electrons. Figure 2 (a) and Figure 3 As shown in (a), when a low bias voltage of 60 mV is applied, the net electric field in the silicon film gradually weakens, and the photocurrent dominated by thermionic electrons generated by the bottom metal absorbing light decreases; simultaneously, the thermionic holes generated by the bottom metal absorbing light are gradually collected under the action of the applied electric field, causing the net photocurrent to decrease with increasing bias voltage, as shown in (a). Figure 2 (b) and Figure 3 As shown in (b), when the applied bias voltage is further increased, the transport contributions of electrons and holes cancel each other out, and the net photocurrent drops to zero; when the bias voltage is further increased to 140 mV, the process of hot holes being collected by the top metal becomes dominant, the polarity of the photocurrent reverses, and it exhibits a negative photocurrent. Furthermore, as the bias voltage continues to increase, the amplitude of the negative photocurrent further increases. Figure 2 (c) and Figure 3 As shown in (c).

[0096] Figure 4 The photoelectric properties of the photodetector in Example 1 are demonstrated, with a focus on its bipolar photoresponse characteristics. For example... Figure 4 As shown in (a), when testing the relationship between photocurrent and incident light power at a wavelength of 1.6 μm, it was found that as the bias voltage increased, the photocurrent direction gradually changed from positive to negative, and the trend transitioned from linear growth to nonlinear growth. When the bias voltage increased further, the photocurrent became completely negative. Figure 4 As shown in (b), by increasing V F The positive photocurrent first gradually decreases to zero, then turns negative and continues to increase. This process clearly demonstrates that, under single-wavelength conditions, the polarity of the photocurrent can be reversibly controlled by adjusting the bias voltage. Figure 4 (c) confirms the good reproducibility of this phenomenon. Figure 4 Figures (d)-(f) illustrate the variation of photocurrent with incident light power at different wavelengths under bias voltages of 0 V, 50 mV, and 140 mV, respectively: the photocurrent gradually transitions from a linear growth mode to a nonlinear growth mode, and finally to a negative growth mode. This evolution process fully reveals the response characteristics and control mechanism of the photodetector to light signals of various wavelengths under different bias voltage conditions.

[0097] Figure 5This demonstrates the relationship between the photocurrent and bias voltage of a photodetector when a fixed set of short-wave infrared incident powers is used. Figure 5 As shown in Figure (a), in the near-infrared band of 1.1 μm-1.8 μm and bias voltage range of 0 mV-130 mV, the positive and negative distribution of photocurrent shows a clear pattern: the positive photocurrent is mainly concentrated in the lower left corner of the figure, corresponding to short wavelength and low bias voltage conditions; while the negative photocurrent is mainly distributed in the upper right corner, corresponding to long wavelength and high bias voltage conditions. Figure 5 (b) shows the characteristic curve extracted from (a) more intuitively: as the bias voltage increases, the photocurrent first turns negative with the increase of wavelength. Figure 5 Figure (c) further illustrates the variation of photocurrent at different wavelengths with bias voltage. The longer the wavelength, the smaller the zero-point bias voltage value at which the photocurrent changes from positive to negative (the zero-point position shifts to the left). This result is completely consistent with the previous analysis, confirming the synergistic regulation mechanism of wavelength and bias voltage on the direction of photocurrent.

[0098] Example 2

[0099] A photodetector, comprising, from bottom to top:

[0100] Bottom metal film (Al): 70 nm thick aluminum film;

[0101] Silicon film (p-Si): 100 nm thick;

[0102] Top metal film (Ti): 20 nm thick titanium film;

[0103] Antireflective layer (PMMA): 200 nm.

[0104] The fabrication method of the above photodetector includes the following steps:

[0105] (1) A commercial silicon-on-insulator (SOI) substrate that has been ultrasonically cleaned with acetone, ethanol and deionized water is placed in a 40% hydrofluoric acid solution. After removing the silicon oxide layer, a 100 nm thick lightly doped p-type silicon film (p-Si) with a resistivity of 10 Ω·cm is obtained suspended in the solution.

[0106] (2) A silicon film layer was retrieved using a silicon oxide wafer with photoresist spin-coated on it. After drying, a 70 nm thick aluminum film layer was deposited using magnetron sputtering technology (pre-sputtering was performed for 5 min before film deposition, and the deposition vacuum degree was 5 × 10⁻⁶). -4 The parameters for magnetron sputtering include: an aluminum target, a power of 50 W, argon gas introduced during sputtering, and an internal pressure of 1 Pa. The sputtered film is then transferred to acetone and allowed to stand to obtain a Si-Al composite film suspended in an organic solvent.

[0107] (3) A Si-Al composite film was retrieved using a silicon oxide wafer sputtered with gold, with the silicon film facing upwards. A 200 μm × 200 μm window was exposed using ultraviolet lithography. Then, a 20 nm thick titanium film was deposited using electron beam evaporation (pre-sputtering was performed for 5 min before film deposition; the parameters for electron beam evaporation included: titanium-gold particles as the evaporating material, an evaporation rate of 0.5 A / s, and a working vacuum of 5 e). -4 The device was then immersed in acetone solution (Pa, operating temperature 20 ℃), left to stand for a period of time, and then removed and air-dried. A layer of PMMA was spin-coated onto the top metal film as an anti-reflection layer to prepare a photodetector with an effective area of ​​200 μm × 200 μm.

[0108] Figure 6 The photoelectric characteristic diagram of the photodetector in Example 2 is shown below. Figure 6 As shown in (a), under a single wavelength of 1.55 μm and constant power (3.7 mW), the photocurrent exhibits a trend of decreasing in the forward direction and increasing in the reverse direction as the bias voltage increases. Subsequently, under constant power (3 mW), different bias voltages were applied, and the photocurrent spectrum in the 1.2–1.8 μm band was measured, as shown in (a). Figure 6 As shown in (b), both the amplitude and polarity of the photocurrent spectrum change with the bias voltage. The polarity of the photocurrent in the near-infrared band can be modulated by the bias voltage, and the bias voltage values ​​required to achieve polarity reversal differ for photocurrents of different wavelengths. This indicates that bipolar photocurrents can be achieved through wavelength selection. Tests were conducted under conditions of 1.55 μm illumination and a 40 mV bias voltage. Figure 6 As shown in (c), the photocurrent initially increases linearly with increasing power, then gradually decreases to zero. When the power increases further, the polarity of the photocurrent reverses. Furthermore, when the power is adjusted from high to low, the trend of the photocurrent change is consistent with that when the power is adjusted from low to high, indicating that the above results are repeatable rather than accidental. Figure 6 As shown in (d), under 1.55 μm illumination and 0 bias voltage, the photocurrent increases linearly with power, consistent with the characteristics of traditional detectors, which conforms to the single-photon-electron conversion process. However, when a small bias voltage is applied, the photocurrent exhibits nonlinear characteristics with power.

[0109] Figure 7 The graph showing the relationship between the photocurrent, bias voltage, incident light wavelength, and power of the photodetector in Example 2 illustrates that the photoresponse characteristics of the bipolar photodetector are synergistically modulated by wavelength, power, and bias voltage. This is significantly different from the characteristics of traditional detectors, which are affected by only a single factor. Furthermore, compared to the bipolar response produced by the traditional pyroelectric effect, the photodetector of this invention exhibits higher stability, response persistence, and repeatability. Figure 7As shown in (a), in the near-infrared band (1.2-1.8 μm, bias voltage 0-100 mV), the positive and negative distributions of photocurrent exhibit a clear pattern: positive photocurrent is mainly concentrated in the short-wavelength incident light and low bias voltage region, while negative photocurrent is mainly distributed in the long-wavelength incident light and high bias voltage region. Figure 7 The graph showing the change of photocurrent extracted from (a) with bias voltage is shown below. Figure 7 As shown in (b), the trend of photocurrent increasing in the opposite direction with increasing bias voltage varies at different wavelengths, but the bias voltage required for the photocurrent generated by high-energy photons (short wavelengths) to achieve polarity reversal is higher. Figure 7 The feature data of zero photocurrent extracted from (a) and the fitting results are as follows: Figure 7 As shown in (c), it can be observed that the bias voltage corresponding to the zero photocurrent increases as the incident light wavelength decreases. Similarly, in Figure 7 Under the constant wavelength conditions of (d)-(f), for incident light of the same wavelength, the photocurrent polarity reversal point can be controlled by the incident light power and bias voltage, and the bias voltage required for the reversal point decreases as the incident light power increases. Figure 7 Under the constant bias conditions of (g)-(i), as the incident light wavelength increases, the nonlinearity of the photocurrent change with bias becomes more significant, and the photocurrent polarity reversal point shifts towards longer wavelengths as the incident light power increases. In summary, high bias, high power incident light, and long wavelength incident light are all beneficial for the photodetector of this invention to generate reverse photocurrent.

[0110] Application examples

[0111] The schematic diagram of the photodetector implementing OR, XOR, and NOT logic functions in Example 1 is shown below. Figure 8 As shown, Figure 8 Figure (a) illustrates the principle of achieving the above three logic functions by adjusting the bias voltage. During the bipolar optical response modulation process, as the bias voltage increases, the zero point of the photocurrent shifts towards shorter wavelengths. Based on this characteristic, selecting 1.3 μm short-wave infrared light (power 4.16 mW) and 1.6 μm short-wave infrared light (power 4.32 mW) with a large wavelength gap as incident light can achieve the best logic input effect. Figure 8 Figure (b) shows the logic output of the Si NM-HCPD under different optical input conditions ("00", "10", "01", "11"), where logic "0" and "1" correspond to the "off" and "on" states of the optical input, respectively. When 1.3 μm and 1.6 μm light are simultaneously irradiated (i.e., "11" input), increasing the bias voltage will cause a negative shift in the total current of the device response (e.g., ...). Figure 8(As shown by the blue curve in (c)). By defining the current range as -2 μA to 0.25 μA for logic "0" output and outside this range for logic "1" output, it can be observed that the logic output of logic "11" input changes from "1" to "0", while the logic output of logic "10" and "01" input remains "1". This achieves OR (10 mV bias) and XOR (20 mV bias) logic functions respectively. Figure 8 As shown in (d) and (e), the upward arrows in the diagram represent logic "1" and the downward arrows represent logic "0". For the NOT (20 mV bias) logic function requiring only a single input, a combination of "10" and "11" inputs is used for demonstration. Its output is the opposite of the input state of 1.6 μm light (e.g., ...). Figure 8 (as shown in (f)). The above results show that, without changing the external circuit, dynamic switching of the three logic functions OR, XOR, and NOT can be achieved simply by adjusting the bias voltage.

[0112] In addition to bias modulation, the photodetector in Example 1 can also implement six basic logic functions: OR, XOR, AND, NAND, NOR, and NOT. Figure 9 As shown in (a). Figure 9 (b) is the truth table of electrical logic outputs of the Si NM-HCPD response optical input ("00", "10", "01", "11"), where the orange text corresponds to the OR, XOR, and AND logic functions implemented under 1.6 μm optical modulation, and the blue text corresponds to the NAND, NOR, and NOT logic functions implemented under 1.4 μm optical modulation.

[0113] At zero bias, by increasing the power of the 1.6 μm modulated light, the measured current shows a negative shift, such as... Figure 9 As shown in (c), 1.2 μm shortwave infrared light (power 3.39 mW) and 1.3 μm shortwave infrared light (power 4.16 mW) were selected as incident light. Based on the preset logic output definition—-2 μA to 0.25 μA is logic "0", and outside this range is logic "1"—as the modulation light power increases, the logic output of the logic "11" input changes from "1" to "0" and then back to "1" in sequence. The corresponding logic function transitions from OR to XOR, and finally to AND. Figure 9 (c) clearly marks the modulation optical power range corresponding to the three logic functions, and the three can be reversibly switched by continuously adjusting the power: when the modulation optical power is reduced, the logic function can be switched from AND (power of 3.10 mW) to XOR (power of 1.31 mW), and then back to OR (power of 93.19 μW). Figure 9In the middle (d), there are three types of IT curves for logic functions, where the red dashed line is the dividing line between logic "0" and "1" outputs.

[0114] Furthermore, the Si NM-HCPD can also achieve reverse logic functionality, in which case 1.4 μm short-wave infrared light is used as the modulation light, such as... Figure 9 As shown in (e), 1.6 μm short-wave infrared light (power 0.37 mW) and 1.7 μm short-wave infrared light (power 0.31 mW) were selected as incident light. As the optical power of the 1.4 μm modulated light increased, the outputs of logic inputs "10" and "01" changed sequentially from "1" to "0" and then back to "1"; while the output of logic input "11" remained "0". This process realizes the transformation from NAND (power 3.07 mW) to NOR (power 3.77 mW) logic function. At the same time, since the logic outputs of "10" and "01" are opposite to the logic output of "00", NOT (power 3.77 mW) logic function can be implemented based on this. Figure 9 In the middle (f), the IT curves for the three logic functions mentioned above are shown, where the red dashed line is the dividing line between logic "0" and "1" outputs.

[0115] 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 should understand that other variations or modifications can be made 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 application of a photodetector in a logic circuit, characterized in that, The photodetector is used for photoelectric logic gates to realize OR, XOR, AND, NAND, NOR, and NOT logic functions; by adjusting the bias voltage, incident light wavelength, and power, the photocurrent direction can be switched from positive to negative, thereby realizing the integration of multiple logic functions in the photodetector. The photodetector includes a bottom electrode layer, a semiconductor layer, and a top electrode layer stacked sequentially. The bottom electrode layer forms a Schottky contact with the semiconductor layer, and the top electrode layer forms a Schottky contact with the semiconductor layer; or, the bottom electrode layer forms a Schottky contact with the semiconductor layer, and the top electrode layer forms an ohmic contact with the semiconductor layer; or, the bottom electrode layer forms an ohmic contact with the semiconductor layer, and the top electrode layer forms a Schottky contact with the semiconductor layer. The material of the semiconductor layer is selected from one or more of Si, Ge, GaAs, InP, GaN and InGaAs.

2. The application according to claim 1, characterized in that, The material of the bottom electrode layer is selected from Au, Ag, Ti, Cu, Cr, Al, alloys containing at least two metallic elements selected from Au, Ag, Ti, Cu, Cr, and Al, TiN, TiO2, SnO2, ZnO, MoO3, WO3, and NiO. x , V2O5, PEDOT:PSS, PTAA, P3HT, Spiro-OMeTAD, PCBM, C 60 One or more of PEIE and TPBi; And / or, the thickness of the semiconductor layer is 5 nm-10 μm; And / or, the material of the top electrode layer is selected from Au, Ag, Ti, Cu, Cr, Al, alloys containing at least two metallic elements selected from Au, Ag, Ti, Cu, Cr, and Al, TiN, TiO2, SnO2, ZnO, MoO3, WO3, and NiO. x , V2O5, PEDOT:PSS, PTAA, P3HT, Spiro-OMeTAD, PCBM, C 60 One or more of PEIE and TPBi.

3. The application according to claim 1, characterized in that, An antireflection layer is provided on the side of the top electrode layer away from the semiconductor layer, and the antireflection layer is made of polymethyl methacrylate.

4. The application according to any one of claims 1-3, characterized in that, Two short-wave infrared beams of different wavelengths are used as incident light inputs. The input states of the incident light include logic "0" and "1", which correspond to "no illumination" and "illumination" of the incident light, respectively. The wavelengths of the two short-wave infrared beams are in the range of 1.1 μm to 2.0 μm. By adjusting the bias voltage applied to the photodetector, the photocurrent response of the photodetector to the incident light input changes; A preset current range is defined as the logic "0" output, and the area outside the preset current range is defined as the logic "1" output, thereby realizing the dynamic switching of OR, XOR, and NOT logic functions.

5. The application according to claim 4, characterized in that, The wavelengths of the two short-wave infrared beams are 1.3 μm and 1.6 μm; the preset current range is -2 μA to 0.25 μA; when neither the 1.3 μm nor the 1.6 μm short-wave infrared beams are irradiated, the input state of the incident light is logic "00"; when only the 1.3 μm short-wave infrared beams are irradiated, the input state of the incident light is logic "10"; when only the 1.6 μm short-wave infrared beams are irradiated, the input state of the incident light is logic "01"; when both the 1.3 μm and 1.6 μm short-wave infrared beams are irradiated simultaneously, the input state of the incident light is logic "11". When implementing the OR logic function, the bias voltage applied to the photodetector is 10 mV; when the input state of the incident light is logic "10", "01", or "11", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00", the output of the photodetector is logic "0". When implementing the XOR logic function, the bias voltage applied to the photodetector is 20 mV; when the input state of the incident light is logic "10" or "01", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00" or "11", the output of the photodetector is logic "0". When implementing the NOT logic function, the bias voltage applied to the photodetector is 20 mV. The output logic "1" indicates that the 1.6 μm short-wave infrared light is not irradiated, and the output logic "0" indicates that the 1.6 μm short-wave infrared light is irradiated. When the input state of the incident light is logic "10", the output of the photodetector is logic "1"; when the input state of the incident light is logic "11", the output of the photodetector is logic "0".

6. The application according to any one of claims 1-3, characterized in that, Two short-wave infrared beams are used as incident light. The input states of the incident light include logic "0" and "1", which correspond to "no illumination" and "illumination" of the incident light, respectively. A beam of short-wave infrared light is used as the modulation light, and the modulation light satisfies the following: the direction of the photocurrent generated by turning on the modulation light alone is opposite to the direction of the photocurrent generated by turning on the incident light alone. By adjusting the power of the modulated light, the photocurrent response of the photodetector to the incident light input changes; A preset current range is defined as the logic "0" output, and the area outside the preset current range is defined as the logic "1" output, thereby realizing the dynamic switching of OR, XOR, AND, NAND, NOR and NOT logic functions.

7. The application according to claim 6, characterized in that, The 1.6 μm shortwave infrared light modulation realizes OR, XOR, and AND logic functions, with the incident light being 1.2 μm and 1.3 μm shortwave infrared light; the preset current range is -2 μA to 0.25 μA; When implementing the OR logic function, the power of the 1.6 μm short-wave infrared light is 93.19 μW; when implementing the XOR logic function, the power of the 1.6 μm short-wave infrared light is 1.31 mW; and when implementing the AND logic function, the power of the 1.6 μm short-wave infrared light is 3.10 mW.

8. The application according to claim 7, characterized in that, When neither 1.2 μm nor 1.3 μm shortwave infrared light is emitted, the input state of the incident light is logic "00"; when only 1.2 μm shortwave infrared light is emitted, the input state of the incident light is logic "10"; when only 1.3 μm shortwave infrared light is emitted, the input state of the incident light is logic "01"; when both 1.2 μm and 1.3 μm shortwave infrared light are emitted simultaneously, the input state of the incident light is logic "11". When implementing the OR logic function, when the input state of the incident light is logic "10", "01", or "11", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00", the output of the photodetector is logic "0". When implementing the XOR logic function, when the input state of the incident light is logic "10" or "01", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00" or "11", the output of the photodetector is logic "0". When implementing the AND logic function, when the input state of the incident light is logic "11", the output of the photodetector is logic "1"; when the input state of the incident light is logic "00", "10", or "01", the output of the photodetector is logic "0".

9. The application according to claim 6, characterized in that, The NAND, NOR, and NOT logic functions are implemented when the 1.4 μm short-wave infrared light is modulated, and the incident light is 1.6 μm and 1.7 μm short-wave infrared light; the preset current range is -2 μA to 0.25 μA; When implementing NAND logic functions, the power of the 1.4 μm short-wave infrared light is 3.07 mW; when implementing NOR logic functions, the power of the 1.4 μm short-wave infrared light is 3.77 mW; when implementing NOT logic functions, the power of the 1.4 μm short-wave infrared light is 3.77 mW.

10. The application according to claim 9, characterized in that, When neither 1.6 μm nor 1.7 μm shortwave infrared light is emitted, the input state of the incident light is logic "00"; when only 1.6 μm shortwave infrared light is emitted, the input state of the incident light is logic "10"; when only 1.7 μm shortwave infrared light is emitted, the input state of the incident light is logic "01"; when both 1.6 μm and 1.7 μm shortwave infrared light are emitted simultaneously, the input state of the incident light is logic "11". When implementing NAND logic functions, when the input state of the incident light is logic "00", "10", or "01", the output of the photodetector is logic "1"; when the input state of the incident light is logic "11", the output of the photodetector is logic "0". When implementing the NOR logic function, when the input state of the incident light is logic "00", the output of the photodetector is logic "1"; when the input state of the incident light is logic "10", "01", or "11", the output of the photodetector is logic "0". When implementing the NOT logic function, when the input state of the incident light is logic "00", the output of the photodetector is logic "1"; when the input state of the incident light is logic "10" or "01", the output of the photodetector is logic "0".

Images