Multifunctional photoelectric logic gate based on copper, indium, phosphorus and sulfur and operation method

Abstract

The invention provides a copper-indium-phosphorus-sulfur-based multifunctional photoelectric logic gate and an operation method. The copper-indium-phosphorus-sulfur-based multifunctional photoelectric logic gate comprises a substrate; the two metal electrodes are respectively arranged at two ends of the upper surface of the substrate; the two layers of graphene electrodes are stacked on the upper surface of the substrate, are positioned between the two metal electrodes and are connected with the metal electrodes; the two-dimensional ferroelectric copper-indium-phosphorus-sulfur material is arranged between the two layers of graphene electrodes to form a three-layer stacked sandwich structure; and the two sets of light sources are arranged above the graphene electrode on the upper layer and irradiate the surface of the two-dimensional ferroelectric copper indium phosphorus sulfur material through the transparent graphene electrode. The photoelectric logic gate is simple in structure and easy to manufacture, bidirectional current control and polarization regulation and control can be achieved on a single device, logic control operation is simple, bidirectional current can be achieved only by adjusting light intensity, extra voltage does not need to be applied to control of the multifunctional logic gate, and the photoelectric logic gate is achieved without voltage adjustment.

Description

Technical Field

[0001] The present application relates to the field of photoelectric logic gate technology, and in particular to a multifunctional photoelectric logic gate based on copper indium phosphorus sulfide and an operation method thereof. Background Art

[0002] Optoelectronic logic gates (OELGs) convert optical input signals into electrical output signals through Boolean logic. They have broad application prospects in machine vision, real-time video analysis, and light detection, and are expected to become a key component of future logic circuits. However, most optoelectronic logic gates currently rely on pn heterojunctions. Due to the unidirectional carrier transport characteristics of pn junctions, they can only realize a single logic gate, and it is difficult to realize multifunctional optoelectronic logic gates. At present, basic logic gates include AND gates, OR gates, NOT gates, XOR gates, NOR gates, and NAND gates. Existing optoelectronic logic gates cannot realize multifunctional optoelectronic logic gates through a single device, and multiple devices are required to achieve them. Based on this, the bidirectional transmission of photocurrent through light regulation has attracted the attention of researchers. This solution is expected to break through the limitations of existing technologies and promote the development of multifunctional optoelectronic logic gates. For example, researchers achieve bidirectional transmission of output current by adjusting the wavelength of light, or achieve bidirectional transmission of photocurrent through the competition mechanism of photovoltaic effect and photothermal effect, or use different redox reactions in electrochemical cells. However, most of these studies require complex device design. How to realize multifunctional optoelectronic logic gates using a single device is a current problem.

[0003] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present application provides a multifunctional photoelectric logic gate based on copper indium phosphide, which utilizes the bulk photovoltaic effect of the material and can achieve bidirectional transmission of photocurrent with only a simple device structure design, thereby providing a solution for realizing a multifunctional photoelectric logic gate in a single simple device, solving the above-mentioned problems.

[0005] This application is implemented through the following technical solutions:

[0006] The first aspect of the present application is to provide a multifunctional photoelectric logic gate based on copper indium phosphide, comprising:

[0007] substrate;

[0008] Two metal electrodes are respectively arranged at two ends of the upper surface of the substrate;

[0009] Two layers of graphene electrodes are stacked on the upper surface of the substrate and located between the two metal electrodes and connected to the metal electrodes;

[0010] A two-dimensional ferroelectric copper indium phosphorus sulfide material is disposed between two layers of graphene electrodes to form a three-layer stacked sandwich structure;

[0011] Two sets of light sources are arranged above the upper graphene electrode, and irradiate the surface of the two-dimensional ferroelectric copper indium phosphorus sulfide material through the transparent graphene electrode;

[0012] By adjusting the switch state and light intensity of the light source, the three functions of the photoelectric logic gate, namely, the OR gate, the NOT gate and the XOR gate, are realized.

[0013] Specifically, the chemical formula of the two-dimensional ferroelectric copper indium phosphorus sulfide material is CuInP2S6, and it is in a film form with a thickness of 200 to 240 nm.

[0014] Specifically, the metal electrode is designed by photolithography, and then exposed and evaporated, and then the metal electrode is mounted on the substrate, so that the substrate with the metal electrodes at both ends can be obtained, and one of the metal electrodes is grounded.

[0015] Specifically, the graphene electrode is in the form of a film with a thickness of 0.4 to 0.7 nm;

[0016] The graphene electrode comprises a first graphene electrode at a lower layer and a second graphene electrode at an upper layer;

[0017] One end of the first graphene electrode is at least partially connected to one of the metal electrodes, one end of the second graphene electrode is at least partially connected to another of the metal electrodes, and the metal electrode to which the second graphene electrode is connected is grounded, and the short-circuit photocurrent generated between the two metal electrodes is used as an output signal.

[0018] Specifically, the first graphene electrode, the two-dimensional ferroelectric copper indium phosphide material, and the second graphene electrode are stacked in sequence from bottom to top along the thickness direction to form the sandwich structure.

[0019] Specifically, the substrate is a Si / SiO2 substrate, wherein the thickness of Si is 490-510 μm, and the thickness of SiO2 is 275-295 nm.

[0020] Specifically, the wavelength range of the two light sources is 320nm to 420nm, and the light intensity of the light sources is adjusted to cause the two-dimensional ferroelectric copper indium phosphorus sulfide material to undergo polarization reversal.

[0021] The second aspect of the present application is to provide an operation method of a multifunctional photoelectric logic gate based on copper indium phosphide, comprising the steps of:

[0022] Obtaining an input logic value generated by the light source and an output logic value of the photocurrent;

[0023] By adjusting the on / off state and light intensity of the light source, different functions of the photoelectric logic gate can be realized.

[0024] Specifically, obtaining the input logic value generated by the light source and the output logic value of the photocurrent includes:

[0025] Determine the input logic value, wherein the input logic value is a two-digit logic value composed of the input logic value of the first light source and the input logic value of the second light source, according to which the on state of any one of the light sources is logic "1" and the off state is logic "0", and the input logic value includes four types: "00", "10", "01", and "11";

[0026] The photocurrent is set to be a short-circuit current at a voltage of 0 V, so that no additional voltage is required during the entire operation;

[0027] The output logic value is set to be "1" when the photocurrent is positive, and the output logic value is set to be "0" when the photocurrent is negative.

[0028] Specifically, by adjusting the on / off state and light intensity of the light source, different functions of the photoelectric logic gate are realized, including:

[0029] Setting the light intensities of the first light source and the second light source so that the photocurrents are all positive when the input logic values ​​are "10", "11" and "01", respectively, and the corresponding output logic values ​​are all "1", so as to realize an OR gate logic function;

[0030] Setting the light intensity of the first light source and the second light source so that when the input logic value is "11", the photocurrent is negative, and the corresponding output logic value is "0", and setting the photocurrent to be positive when the input logic value is "10" or "01", and the corresponding output logic is "1", so as to realize an XOR gate logic function;

[0031] The first light source is set to be normally on, and the second light source is adjusted to be on or off, that is, the input logic value is "(1)0" or "(1)1". By setting the light intensity of the first light source and the second light source, when the input logic value is "(1)0", the output photocurrent is positive, that is, the output logic value is "1", and when the input logic value is "(1)1", the output photocurrent is negative, that is, the output logic value is "0", so as to realize the NOT gate logic function.

[0032] Compared with the prior art, the present application has the following major beneficial effects: (1) through simple material and structural design, a photoelectric logic gate having three functions of OR gate, NOT gate and XOR gate can be realized in a single device, which is easy to prepare and has multiple functions; (2) a single device can realize bidirectional current control and polarization regulation; (3) the operation of logic control is simple, and bidirectional current can be realized by only adjusting the light intensity, and the control of the multifunctional logic gate does not require the application of additional voltage, and there is no need to realize the photoelectric logic gate by adjusting the voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 This is a schematic structural diagram of a multifunctional photoelectric logic gate device based on copper indium phosphorus sulfide according to an embodiment of the present application.

[0035] Figure 2 This is a schematic diagram of a multifunctional photoelectric logic gate based on copper indium phosphide according to an embodiment of the present application.

[0036] Figure 3 4 is a corresponding diagram of light intensity and output current polarization direction according to an embodiment of the present application.

[0037] Figure 4 This is a logic control schematic diagram of a copper indium phosphide-based multifunctional photoelectric logic gate according to an embodiment of the present application.

[0038] Figure numerals: 1 - substrate; 2 - metal electrode; 3 - graphene electrode; 4 - two-dimensional ferroelectric CuInP2S6 material; 5 - light source. DETAILED DESCRIPTION

[0039] The following will be combined with the implementation methods of this application to clearly and completely describe the technical solutions in the implementation methods of this application. Obviously, the described implementation methods are only part of the implementation methods of this application, not all of the implementation methods. Based on the implementation methods in this application, all other implementation methods obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] It should be understood that the terms used in this specification of the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the embodiments of the present application. As used in the specification of the embodiments of the present application and the appended claims, unless the context clearly indicates otherwise, the singular forms of "a", "an" and "the" are intended to include plural forms.

[0041] It should be understood that the terms "up", "down", "left", "right", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, and a specific direction structure and operation. Therefore, they should not be understood as limitations on the present invention.

[0042] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0043] Optoelectronic logic gate (OELG) converts optical input signals into electrical output signals through Boolean logic to achieve logical judgment. It has broad application prospects in machine vision, real-time video analysis, and light detection, and is expected to become a key component of future logic circuits. However, most optoelectronic logic gates currently rely on pn heterojunctions. Due to the unidirectional carrier transport characteristics of pn junctions, they can only realize a single logic gate, and it is difficult to realize multifunctional optoelectronic logic gates. At present, basic logic gates include AND gates, OR gates, NOT gates, XOR gates, NOR gates, and NAND gates. Existing optoelectronic logic gates cannot realize multifunctional optoelectronic logic gates through a single device, or if a multifunctional optoelectronic logic gate is realized, a complex device structure needs to be designed. Based on this, the bidirectional transmission of photocurrent through light regulation has attracted the attention of researchers. This solution is expected to break through the limitations of existing technologies and promote the development of multifunctional optoelectronic logic gates. For example, researchers have achieved bidirectional transmission of output current by adjusting the wavelength of light, or by the competition mechanism between the photovoltaic effect and the photothermal effect, or by using different redox reactions in electrochemical cells. However, most of these studies require complex device design. How to use a single device to realize a multifunctional optoelectronic logic gate is a current problem.

[0044] Copper indium phosphide is a room-temperature two-dimensional ferroelectric material that has stable ferroelectric polarization at a thickness of 4 nm.

[0045] The bulk photovoltaic effect (BPVE) exists in materials with broken symmetry and can generate open-circuit voltages and short-circuit photocurrents that exceed the band gap. Based on the bulk photovoltaic effect, ferroelectric materials can generate short-circuit photocurrents associated with their polarization direction using their own spontaneous polarization. In addition, based on the characteristics of the ferroelectric polarization of CIPS associated with the displacement of Cu ions therein, the reversible ferroelectric polarization flipping of CIPS under global and local light fields is further achieved through the photothermal effect, thereby realizing the bidirectional transmission of device photocurrent.

[0046] Copper indium phosphide CuInP2S6 (CIPS) is a typical two-dimensional ferroelectric material with bulk photovoltaic effect (BPVE). Two-dimensional CIPS thin films can be obtained by mechanical exfoliation of CIPS crystals. + The displacements of the Cu in CIPS are coupled to each other, and the photothermal effect can be used to drive + The displacement of CIPS can achieve the effect of regulating the polarization direction of CIPS. In addition, combined with the bulk photovoltaic effect of the material itself, while the photothermal effect brings about polarization reversal, it can also achieve the effect of regulating the direction of photocurrent and the magnitude of current. Therefore, this application designs a multifunctional logic gate based on CIPS material, which can obtain a sandwich structure device by simply transferring and stacking two-dimensional materials, thereby realizing a multifunctional optoelectronic logic gate in a single device.

[0047] The first aspect of the present application is to provide a multifunctional photoelectric logic gate based on copper indium phosphide, such as Figure 1 As shown, it is a device structure diagram of a multifunctional photoelectric logic gate in an embodiment, which includes, from bottom to top, a substrate 1, two metal electrodes 2, two layers of graphene electrodes 3, a two-dimensional ferroelectric copper indium phosphorus sulfide material 4 and two sets of light sources 5.

[0048] Specifically, the substrate 1 is a Si / SiO2 substrate, the thickness of Si is 490-510 μm, and the thickness of SiO2 is 275-295 nm.

[0049] Specifically, two metal electrodes 2 are arranged at both ends of the upper surface of the substrate, and a certain distance is kept between each other to accommodate the sandwich structure composed of the graphene electrode and the copper indium phosphorus sulfur material. Specifically, the metal electrode 2 includes a first electrode and a second electrode, which are respectively located at both ends of the upper surface of the substrate, wherein the second electrode is grounded. The material for making the metal electrode can be gold, silver, copper, platinum, palladium, iridium and some alloys thereof with good electrical conductivity. In one embodiment, the material for making the metal electrode is gold.

[0050] In one embodiment, the metal electrode 2 is designed by photolithography, and then the pattern is exposed and evaporated, and then the metal electrode 2 is installed on the substrate 1 to obtain a substrate with metal electrodes at both ends, and the side with the metal electrodes is facing upward, and one of the metal electrodes is grounded to form an output circuit.

[0051] The graphene electrode 3 is a two-dimensional (2D) material in the form of a film with a thickness of 0.4 to 0.7 nm. The graphene material has excellent thermal conductivity and has good electron transmission channels and stability. The two layers of graphene electrodes 3 are stacked on the upper surface of the substrate in the vertical direction and are located between the two metal electrodes 2 in the horizontal direction, and are connected to the metal electrodes 2 respectively. The graphene electrode is a transparent material, so that the light source can shine through the graphene on the surface of the two-dimensional ferroelectric material. The connection method of the two graphene electrodes and the two metal electrodes is specifically that one graphene electrode is connected to one metal electrode, and the other graphene electrode is connected to the other metal electrode. The contact surface of the connection is the surface of the metal electrode, and the connection is made by van der Waals force.

[0052] Specifically, in one embodiment, one of the metal electrodes 2 is a first metal electrode, and the other metal electrode 2 is a second metal electrode. The graphene electrode 3 includes a first graphene electrode in a lower layer and a second graphene electrode in an upper layer, one end of the first graphene electrode is at least partially connected to the first metal electrode, one end of the second graphene electrode is at least partially connected to the second metal electrode, and the second graphene electrode is grounded through the metal electrode to form a short-circuit current, which can be used as an output signal. The direction and size of the short-circuit current can be controlled by the light source switch and the light intensity, thereby obtaining a multifunctional logic gate device.

[0053] One end of the first graphene electrode is at least partially connected to one of the metal electrodes, one end of the second graphene electrode is at least partially connected to another of the metal electrodes, and the metal electrode to which the second graphene electrode is connected is grounded, and the short-circuit photocurrent generated between the two metal electrodes is used as an output signal.

[0054] In one embodiment, the short-circuit current at a voltage of 0 V is realized without applying an additional voltage during the entire operation. Preferably, the voltage of the short-circuit current can be set to 0 V, that is, logic gates with different functions can be realized without applying an additional voltage, and logic gates can be realized without adjusting the voltage, making the operation convenient, and simple devices can realize logic gates with different functions.

[0055] In one embodiment, when the short-circuit current (photocurrent) is positive, the output is logic "1", and when the short-circuit current (photocurrent) is negative, the output is logic "0". The positive or negative value of the photocurrent is related to the magnitude of the light intensity.

[0056] The two-dimensional ferroelectric copper indium phosphorus sulfide material 4 is also a two-dimensional (2D) material, in the form of a film with a thickness of 200 to 240 nm, and is disposed between the two layers of the graphene electrode 3 to form a sandwich structure with three layers of two-dimensional structures stacked. Due to its own bulk photovoltaic effect, the two-dimensional ferroelectric CIPS material associates the direction of the photocurrent with the polarization direction of the ferroelectric material, and realizes the reversible ferroelectric polarization reversal of CIPS under global and local light fields through the photothermal effect, thereby realizing the bidirectional transmission of the device's photocurrent. Photocurrent refers to the current when the voltage is 0V under light. The photothermal effect refers to the change in the Cu in the two-dimensional ferroelectric CIPS material after the upper layer of the sandwich structure is exposed to light. + Driven by the temperature gradient, a displacement occurs, which in turn changes the ferroelectric polarization direction of CIPS, thereby changing the direction of its photocurrent.

[0057] The stacking between the sandwich structures is achieved through van der Waals forces, and the contact surfaces between the metal electrodes and the graphene electrodes are also stacked through van der Waals forces.

[0058] Two sets of light sources 5 are arranged above the graphene electrode 3 of the upper layer, that is, above the second graphene electrode, and irradiate vertically on the upper surface of the graphene electrode 3 of the upper layer. The graphene electrode is a transparent material, so the light source can penetrate the graphene electrode and irradiate on the surface of the two-dimensional ferroelectric copper indium phosphorus sulfur material 4. The two sets of light sources 5 include a first light source (Light-1) and a second light source (Light-2), and the wavelength range is 320nm to 420nm. Adjusting the light intensity of the light source can cause the polarization of the CIPS material to flip. Any light source 5 irradiates the surface of the second graphene electrode to generate an input light signal, the first light source (Light-1) generates a first light input signal, and the second light source (Light-2) generates a second light input signal. The on state (that is, the light source is on) of any light source 5 is defined as logic "1", and the off state (the light source is off) is defined as logic "0", which can realize three light input logics of "10", "01", and "11". When both light sources are off, that is, the input logic value is "00", and no photocurrent is generated.

[0059] The materials of the various components constituting the structure of this application are easy to obtain and the structure is simple. Polarization reversal and bidirectional photocurrent transmission can be achieved by utilizing the material properties of copper indium phosphide itself.

[0060] like Figure 2 Shown is a schematic diagram of a multifunctional photoelectric logic gate based on copper indium phosphide of the present application.

[0061] In such Figure 2 In (a), the light intensity of the two light sources is set at a certain value, Cu + At the top of CIPS, by adjusting the light intensity, Cu + Downward displacement reaches Figure 2 The bottom of the CIPS shown in (b) is removed, thereby changing the polarization direction of the CIPS.

[0062] like Figure 3 The figure shows the output current corresponding to different light intensities in one embodiment of the present application. 2 As the light intensity increases, the current intensity also increases and is always positive. When the light intensity continues to increase and exceeds 0.45W / cm 2 After that, the current polarization reverses and forms a negative current. The specific principle is as follows Figure 2 As shown, increasing the light intensity to a certain value can make Cu + The polarization is reversed by shifting downward. Therefore, different photoelectric logic gate functions can be realized by adjusting the light intensity with the help of the properties of copper indium phosphide materials.

[0063] The second aspect of the present application is to provide an operation method of a multifunctional photoelectric logic gate based on copper indium phosphide, which realizes a multifunctional photoelectric logic gate by controlling light intensity and utilizing material properties, and specifically comprises the following steps:

[0064] S1, obtaining the input logic value generated by the light source and the output logic value of the photocurrent;

[0065] S2. Realize different functions of the photoelectric logic gate by adjusting the switch state or light intensity of the light source.

[0066] Specifically, step S1, obtaining an input logic value generated by a light source and an output logic value of a photocurrent, comprises:

[0067] S11, determining the input logic value, wherein the input logic value is a two-digit logic value composed of the input logic value of the first light source and the input logic value of the second light source, according to which the on state of any one of the light sources is logic "1" and the off state is logic "0", and the input logic value includes four types: "00", "10", "01", and "11";

[0068] S12, setting the voltage to a short-circuit current at 0V, so that no additional voltage is required during the entire operation;

[0069] S13, setting the output logic value to "1" when the photocurrent is positive, and setting the output logic value to "0" when the photocurrent is negative.

[0070] like Figure 4 As shown in a, there are four types of input logic, namely 00 when both light sources are in the off state, "10" when the first light source is in the on state and the second light source is in the off state, "01" when the first light source is in the off state and the second light source is in the on state, and "11" when both light sources are in the on state.

[0071] Specifically, step S2, realizing different functions of the photoelectric logic gate by adjusting the switch state or light intensity of the light source, includes:

[0072] S21. Set the light intensity of the first light source and the second light source so that the photocurrents are all positive when the input logic values ​​are "10", "11" and "01", respectively, and the corresponding output logic values ​​are all "1", so as to realize the OR gate logic function.

[0073] In one embodiment, if Figure 4 As shown in b, the light intensity of the first light source is set to 0.25 W / cm 2 , and the light intensity of the second light source is 0.14 W / cm 2 When the input logic is set to "10", "11" and "01", the corresponding output current is positive, so the output logic is "1" to realize the OR gate OR logic function.

[0074] Step S2 also includes: S22, setting the light intensity of the first light source and the second light source so that when the input logic value is "11", the output current is negative, and the corresponding output logic value is "0", and setting the output current to be positive when the input logic value is "10" or "01", and the corresponding output logic is "1", so as to realize the XOR gate logic function.

[0075] In one embodiment, if Figure 4 As shown in c, the light intensity of the first light source is set to 0.42 W / cm 2 , and the light intensity of the second light source is 0.20 W / cm 2 , when the input logic is set to "11", the total light intensity is 0.62W / cm 2 , the corresponding current is negative, so the output logic is "0", and when the input logic is "10" or "01", the corresponding current is positive, so the output logic is "1", so as to realize the XOR logic function of the XOR gate.

[0076] Step S2 also includes: S23, setting the first light source to be normally on, and adjusting the second light source to be on or off, that is, the input logic value is "10" or "11", and by setting the light intensity of the first light source and the second light source, the output logic value is "1" or "0" to realize the NOT gate logic function.

[0077] In one embodiment, if Figure 4 As shown in d, the first light source is set to be always on, and the light intensity is 0.31 W / cm 2When the second light source is adjusted to the off state, the light intensity of the system is equal to the light intensity of the first light source, 0.31 W / cm 2 , the input logic is "(1)0", the output photocurrent is positive, the output logic is "1", when the second light source is adjusted to the on state, and the light intensity of the second light source is 0.20W / cm 2 , the total light intensity is 0.51W / cm 2 , the input logic is "(1)1", and the corresponding output photocurrent is negative, that is, the output logic value is "0", so as to realize the NOT logic function of the NOT gate.

[0078] Similarly, the second light source can be set to a normally-on state, and the first light source can be on or off. By setting the light intensity, the NOT logic function can also be realized.

[0079] Understandably, Figure 3 and Figure 4 The corresponding light intensity and current positive and negative are the performance of a two-dimensional ferroelectric copper indium phosphorus sulfide material with a thickness of 200-240nm at 0V in an embodiment of the present application, which can be replaced by other two-dimensional ferroelectric materials or other materials with the same effect. The specific light intensity value can also be in other ranges.

[0080] In summary, the present application provides a multifunctional photoelectric logic gate based on copper indium phosphorus sulfur, including: a substrate; two metal electrodes, respectively arranged at the two ends of the upper surface of the substrate; two layers of graphene electrodes, stacked on the upper surface of the substrate, and located between the two metal electrodes and connected to the metal electrodes; a two-dimensional ferroelectric copper indium phosphorus sulfur material, arranged between the two layers of graphene electrodes, forming a three-layer stacked sandwich structure; two sets of light sources, arranged above the upper graphene electrode, irradiating the surface of the two-dimensional ferroelectric copper indium phosphorus sulfur material through the transparent graphene electrode; by regulating the light signal generated by the light source as an input signal, the three functions of the photoelectric logic gate, namely, the OR gate, the NOT gate, and the XOR gate, are realized. By setting different light intensities, utilizing the bulk photovoltaic effect of the two-dimensional ferroelectric copper indium phosphorus sulfur material, and defining the on-off logic value of the light source and the positive and negative logic values ​​of the short-circuit current, the three photoelectric logic gates, namely, the OR gate, the NOT gate, and the XOR gate, are realized. The structure of the present application is simple, the materials are easily available and easy to prepare, and bidirectional current control and polarization regulation can be achieved on a single device. The logic control operation is simple, and bidirectional current can be achieved by simply adjusting the light intensity. The control of the multifunctional logic gate does not require the application of additional voltage, and there is no need to realize the photoelectric logic gate by adjusting the voltage.

[0081] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention.

Claims

1. A multifunctional photoelectric logic gate based on copper indium phosphide, characterized in that: include: substrate; Two metal electrodes are respectively arranged at two ends of the upper surface of the substrate; Two layers of graphene electrodes are stacked on the upper surface of the substrate and located between the two metal electrodes and connected to the metal electrodes; A two-dimensional ferroelectric copper indium phosphorus sulfide material is disposed between two layers of graphene electrodes to form a three-layer stacked sandwich structure; Two sets of light sources are arranged above the upper graphene electrode, and irradiate the surface of the two-dimensional ferroelectric copper indium phosphorus sulfide material through the transparent graphene electrode; By adjusting the switch state and light intensity of the light source, the three functions of the photoelectric logic gate, namely, the OR gate, the NOT gate and the XOR gate, are realized.

2. A multifunctional photoelectric logic gate based on copper indium phosphide according to claim 1, characterized in that: The chemical formula of the two-dimensional ferroelectric copper indium phosphorus sulfide material is CuInP2S6, and it is in film form with a thickness of 200 to 240 nm.

3. A multifunctional photoelectric logic gate based on copper indium phosphide according to claim 1, characterized in that: The metal electrode is designed by photolithography, and then exposed and evaporated, and then the metal electrode is mounted on the substrate, so that the substrate with the metal electrodes at both ends can be obtained, and one of the metal electrodes is grounded.

4. A multifunctional photoelectric logic gate based on copper indium phosphide according to claim 3, characterized in that: The graphene electrode is in the form of a film with a thickness of 0.4 to 0.7 nm; The graphene electrode comprises a first graphene electrode and a second graphene electrode; One end of the first graphene electrode is at least partially connected to one of the metal electrodes, one end of the second graphene electrode is at least partially connected to another of the metal electrodes, and the metal electrode to which the second graphene electrode is connected is grounded, and the short-circuit photocurrent generated between the two metal electrodes is used as an output signal.

5. A multifunctional photoelectric logic gate based on copper indium phosphide according to claim 4, characterized in that: The first graphene electrode, the two-dimensional ferroelectric copper indium phosphide material, and the second graphene electrode are stacked in sequence from bottom to top along the thickness direction to form the sandwich structure.

6. The multifunctional photoelectric logic gate based on copper indium phosphide according to claim 1, characterized in that: The substrate is a Si / SiO2 substrate, wherein the thickness of Si is 490-510 μm, and the thickness of SiO2 is 275-295 nm.

7. The multifunctional photoelectric logic gate based on copper indium phosphide according to claim 1, characterized in that: The wavelength range of the two light sources is 320nm to 420nm. The light intensity of the light sources is adjusted to cause the two-dimensional ferroelectric copper indium phosphorus sulfide material to produce polarization reversal.

8. An operating method using the copper indium phosphide-based multifunctional photoelectric logic gate according to any one of claims 1 to 7, characterized in that: Includes steps: Obtaining an input logic value generated by the light source and an output logic value of the photocurrent; By adjusting the on / off state and light intensity of the light source, different functions of the photoelectric logic gate can be realized.

9. The operating method according to claim 8, characterized in that: The step of obtaining the input logic value generated by the light source and the output logic value of the photocurrent comprises: Determine the input logic value, wherein the input logic value is a two-digit logic value composed of the input logic value of the first light source and the input logic value of the second light source, according to which the on state of any one of the light sources is logic "1" and the off state is logic "0", and the input logic value includes four types: "00", "10", "01", and "11"; The photocurrent is set to be a short-circuit current at a voltage of 0 V, so that no additional voltage is required during the entire operation; When the photocurrent is positive, the output logic value is set to "1", and when the photocurrent is negative, the output logic value is set to "0".

10. The operating method according to claim 9, characterized in that: By adjusting the switch state and light intensity of the light source, different functions of the photoelectric logic gate are realized, including: The light intensities of the first light source and the second light source are set so that the photocurrents are all positive when the input logic values ​​are "10", "11", and "01", respectively, and the corresponding output logic values ​​are all "1", so as to realize an OR gate logic function; The light intensity of the first light source and the second light source is set so that when the input logic value is "11", the photocurrent is negative, and the corresponding output logic value is "0", and when the input logic value is "10" or "01", the photocurrent is positive, and the corresponding output logic is "1", so as to realize an XOR gate logic function; The first light source is set to be normally on, and the second light source is adjusted to be on or off, that is, the input logic value is "(1)0" or "(1)1". By setting the light intensity of the first light source and the second light source, when the input logic value is "(1)0", the output photocurrent is positive, that is, the output logic value is "1", and when the input logic value is "(1)1", the output photocurrent is negative, that is, the output logic value is "0", so as to realize the NOT gate logic function.

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