Perovskite heterojunction detector, underwater optical communication component, system and method

Abstract

Embodiments of the present invention provide a perovskite heterojunction detector, an underwater optical communication component, a system, and a method. The perovskite heterojunction detector includes: a 3D perovskite layer, a 2D perovskite layer covering the upper surface of the 3D perovskite layer, a first electrode layer covering the upper surface of the 2D perovskite layer, and a second electrode layer covering the lower surface of the 3D perovskite layer.

Description

Technical Field

[0001] The present invention relates to the field of perovskite photodetectors, and in particular to a perovskite heterojunction detector, an underwater optical communication component, a system and a method. Background Art

[0002] Underwater communication is generally categorized into three technologies: underwater acoustic wave communication, underwater radio frequency electromagnetic communication, and underwater optical communication. Underwater acoustic wave communication is currently the most widely used underwater communication technology, with a communication range of up to 20 kilometers. However, its limitations include low transmission rates, long communication delays, high costs, high power consumption, and harm to marine life. Underwater radio frequency electromagnetic communication offers a moderate data transmission rate of 100Mbps and is resistant to water turbulence and turbidity interference, but its communication range is short, the transceiver is bulky, the cost is high, and the power consumption is high. In contrast, underwater optical communication offers a fast data transmission rate (Gbps level), low cost and compact transceivers, strong anti-interference capabilities, and high security, making it a key research technology in the field of underwater communications in the future. Currently, light intensity modulation is a commonly used modulation technique in underwater optical communication systems. However, the inventors have discovered that this technology has some limitations. Factors such as light scattering, absorption, and attenuation in underwater environments can cause signal distortion and damage, making it difficult to use in turbid, complex terrain and fluctuating water flow environments.

[0003] In the process of implementing the present invention, the applicant discovered that the prior art has the following problems:

[0004] The existing underwater optical communication method based on light intensity modulation is susceptible to signal distortion and damage caused by factors such as light scattering, absorption and attenuation in the underwater environment, making underwater optical communication difficult in turbid, complex terrain and changing water flow environments. Summary of the Invention

[0005] The embodiments of the present invention provide a perovskite heterojunction detector, an underwater optical communication component, a system and a method to solve the problem that the existing underwater optical communication method based on light intensity modulation, the scattering, absorption and attenuation of light in the underwater environment will cause signal distortion and damage, making underwater optical communication difficult in turbid and complex terrain and water flow changing environment.

[0006] To achieve the above objectives, in a first aspect, an embodiment of the present invention provides a perovskite heterojunction detector, specifically a perovskite heterojunction bandpass detector, and also a perovskite heterojunction bandpass photodetector, comprising: a 3D perovskite layer, a 2D perovskite layer covering an upper surface of the 3D perovskite layer, a first electrode layer covering an upper surface of the 2D perovskite layer, and a second electrode layer covering a lower surface of the 3D perovskite layer;

[0007] The band gap of the material of the 2D perovskite layer is greater than the band gap of the material of the 3D perovskite layer, the exciton binding energy of the material of the 2D perovskite layer is greater than the exciton binding energy of the material of the 3D perovskite layer, the thickness of the 2D perovskite layer is a first preset thickness, and the thickness of the 3D perovskite layer is a second preset thickness, so that the perovskite heterojunction detector generates an electrical signal response to excitation light greater than or equal to a preset starting wavelength and less than or equal to a preset cut-off wavelength, and does not generate an electrical signal response to excitation light less than the preset starting wavelength or greater than the preset cut-off wavelength; the preset starting wavelength is determined by the material of the 2D perovskite layer and the first preset thickness, and the preset cut-off wavelength is determined by the material of the 3D perovskite layer and the second preset thickness.

[0008] In a second aspect, an embodiment of the present invention provides an underwater optical communication component based on a perovskite heterojunction detector, comprising: at least one perovskite heterojunction detector group;

[0009] Each perovskite heterojunction detector group includes at least one perovskite heterojunction detector as described above;

[0010] All perovskite heterojunction detectors are arranged in a preset arrangement pattern.

[0011] Among them, the perovskite heterojunction detectors in the same perovskite heterojunction detector group have the same preset starting wavelength, and the perovskite heterojunction detectors in different perovskite heterojunction detector groups have different preset starting wavelengths.

[0012] In a third aspect, an embodiment of the present invention provides an underwater optical communication system based on a perovskite heterojunction detector, comprising:

[0013] The underwater optical communication component based on the perovskite heterojunction detector, the excitation light emitting device, and the control and acquisition system for collecting the electrical signals output by the underwater optical communication component as described above;

[0014] The excitation light emitting device is used to modulate communication data into excitation light having at least one central wavelength according to a preset communication protocol, and emit the excitation light;

[0015] The underwater optical communication component is used to receive the excitation light and output an electrical signal corresponding to the excitation light;

[0016] The control and acquisition system is used to collect the electrical signal corresponding to the excitation light and convert the electrical signal into the communication data.

[0017] In a fourth aspect, an embodiment of the present invention provides an underwater optical communication method based on a perovskite heterojunction detector, comprising:

[0018] The excitation light emitting device modulates the communication data into excitation light having at least one central wavelength according to a preset communication protocol, and emits the excitation light;

[0019] The underwater optical communication component based on the perovskite heterojunction detector as described above receives the excitation light and outputs an electrical signal corresponding to the excitation light;

[0020] The control acquisition system acquires the electrical signal corresponding to the excitation light and converts the electrical signal into the communication data.

[0021] The above technical solution has the following beneficial effects: by adjusting the thickness and material composition of the 2D and 3D perovskite layers, the 2D and 3D perovskite layers form a perovskite heterojunction detector, namely a 2D / 3D perovskite heterojunction bandpass photodetector, which can identify excitation light of different wavelengths, thereby enabling wavelength-modulated underwater optical communication. Compared to conventional light intensity modulation underwater optical communication, wavelength modulation has the advantage of being insensitive to changes in the underwater light propagation path and environment, resulting in a low bit error rate and enabling beyond-line-of-sight communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 This is a schematic structural diagram of a perovskite heterojunction detector according to one embodiment of the present invention;

[0024] Figure 2 This is a schematic structural diagram of an underwater optical communication component based on a perovskite heterojunction detector according to one embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the architecture of an underwater optical communication system based on a perovskite heterojunction detector according to one embodiment of the present invention;

[0026] Figure 4 This is a flow chart of an underwater optical communication method based on a perovskite heterojunction detector according to one embodiment of the present invention;

[0027] Figure 5 This is an excitation light response curve of an underwater optical communication component composed of four perovskite heterojunction detectors according to one embodiment of the present invention;

[0028] Figure 6This is a schematic diagram of the three-dimensional structure of four perovskite heterojunction detectors sharing a 3D perovskite layer according to one embodiment of the present invention;

[0029] Figure 7 This is a comparative diagram of underwater environmental absorption coefficients of emission spectra of four LED light sources with central wavelengths of 374 nm, 400 nm, 428 nm, and 450 nm, respectively, and the corresponding detector bandpass response wavelength ranges according to one embodiment of the present invention;

[0030] Figure 8 The photocurrent responses of four 2D / 3D perovskite heterojunction bandpass photodetectors under an external bias of +8V under illumination of four LED light pulses with different central wavelengths according to one embodiment of the present invention;

[0031] Figure 9 This is the external quantum efficiency (EQE) spectra of four 2D / 3D perovskite heterojunction devices based on 3D perovskite MAPbI3 according to one embodiment of the present invention.

[0032] The figure numbers are represented as: 10, first electrode layer; 11, 2D perovskite layer; 12, 3D perovskite layer; 13, second electrode layer; 21, perovskite heterojunction detector group; 22, perovskite heterojunction detector; 30, underwater optical communication component; 31, excitation light emitting device; 32, control and acquisition system; 321, controller; 322, differential identification unit; 51, first response starting edge; 52, second response starting edge; 53, third response starting edge; 54, fourth response starting edge; 71, first excitation light center wavelength; 72, second excitation light center wavelength; 73, third excitation light center wavelength; 74, fourth excitation light center wavelength; 711, first bandpass wavelength range; 721, second bandpass wavelength range; 731, third bandpass wavelength range; 741, fourth bandpass wavelength range. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] Compared with light intensity modulation, wavelength modulation uses wavelength to encode information. The clear wavelength size can transmit information through diffuse reflection and multi-path, and can also stably output information in turbid and complex water bodies and water flow changing environments without causing information distortion, greatly reducing the bit error rate. Perovskite, as a third-generation semiconductor material, has low cost, simple preparation, adjustable band gap, and excellent photoelectric performance, and is suitable for preparing optoelectronic / electronic devices with specific functions. In the field of perovskite photovoltaics, 2D / 3D perovskite heterostructures are generally used to improve the efficiency and stability of solar cell devices, but research on using 2D / 3D perovskite heterojunction bandpass detectors for underwater optical communications has not yet been reported. The embodiment of the present invention specifically uses a group of 2D / 3D perovskite heterojunction detectors to achieve wavelength-modulated underwater optical communication (that is, the light source is composed of multiple light signals of different wavelengths, and one wavelength represents one binary bit). Compared with common intensity-modulated optical communication, the advantage of wavelength modulation is that the wavelength is not sensitive to changes in the underwater light propagation path, so the bit error rate is low and beyond-line-of-sight communication can be achieved.

[0035] First, as Figure 1 As shown, an embodiment of the present invention provides a perovskite heterojunction detector, comprising:

[0036] A 3D perovskite layer 12, a 2D perovskite layer 11 covering an upper surface of the 3D perovskite layer 12, a first electrode layer 10 covering an upper surface of the 2D perovskite layer 11, and a second electrode layer 13 covering a lower surface of the 3D perovskite layer;

[0037] The band gap of the material of the 2D perovskite layer 11 is greater than the band gap of the material of the 3D perovskite layer 12, the exciton binding energy of the material of the 2D perovskite layer 11 is greater than the exciton binding energy of the material of the 3D perovskite layer 12, the thickness of the 2D perovskite layer 11 is a first preset thickness, and the thickness of the 3D perovskite layer is a second preset thickness, so that the perovskite heterojunction detector generates an electrical signal response to excitation light greater than or equal to a preset starting wavelength and less than or equal to a preset cut-off wavelength, and does not generate an electrical signal response to excitation light less than the preset starting wavelength or greater than the preset cut-off wavelength; the preset starting wavelength is determined by the material of the 2D perovskite layer 11 and the first preset thickness, and the preset cut-off wavelength is determined by the material of the 3D perovskite layer 12 and the second preset thickness.

[0038] In some embodiments, the material of the 2D perovskite layer 11 has a relatively large bandgap and high exciton binding energy, resulting in a weaker photoelectric conversion capability. The material of the 3D perovskite layer 12, on the other hand, has a relatively small bandgap and low exciton binding energy, resulting in a higher photoelectric conversion capability. The 2D perovskite layer 11 is used to filter out excitation light with wavelengths less than a preset starting wavelength, preventing it from reaching the 3D perovskite layer 12 and being converted into an electrical signal. Excitation light with wavelengths greater than the preset starting wavelength and less than the preset cutoff wavelength can be absorbed by the 3D perovskite layer 12 and converted into an electrical signal. The perovskite heterojunction detector forms a bandpass detector for excitation light, with a bandpass wavelength range from a preset starting wavelength to a preset cutoff wavelength. By controlling the material and thickness of the 2D perovskite layer 11 and the material and thickness of the 3D perovskite layer 12, perovskite heterojunction detectors with different bandpass wavelength ranges can be obtained. It generates an electrical signal in response to excitation light with wavelengths within the passband, but not to excitation light with wavelengths outside the passband. It should be noted that the surface of the 3D perovskite layer typically contains a high density of defects. Due to surface charge quenching, the device's external quantum efficiency (EQE) is narrowband. When a thin layer of 2D perovskite is applied to the 3D perovskite layer, the surface defects are passivated by the 2D perovskite, and the device's EQE shifts from narrowband to broadband. Only when the 2D perovskite layer is thicker (e.g., 2 to 3 microns) can it act as a filter, transforming the device into a bandpass photodetector. The response start edge (preset start wavelength) of the bandpass device is primarily determined by the composition of the 2D perovskite layer. The response end edge (preset cutoff wavelength) of the bandpass photodetector is determined by the material of the 3D perovskite layer.

[0039] The embodiments of the present invention have the following technical effects: by adjusting the thickness and material composition of the 2D and 3D perovskite layers, the 2D and 3D perovskite layers form a perovskite heterojunction detector, namely a 2D / 3D perovskite heterojunction bandpass photodetector, which can identify excitation light of different wavelengths, thereby enabling wavelength-modulated underwater optical communication. Compared to conventional light intensity modulation underwater optical communication, wavelength modulation has the advantage of being insensitive to changes in the underwater light propagation path and environment, resulting in a low bit error rate and enabling beyond-line-of-sight communication.

[0040] Furthermore, the composition structure of the material of the 3D perovskite layer is ABX3, wherein A is a monovalent cation, B is a divalent metal cation, and X is a halogen anion.

[0041] In some embodiments, the monovalent cation comprises an organic amine ion or a metal cation; the organic amine ion comprises: NH=CHNH3 + (FA+ , formamidinium ion) and CH3NH3 + (MA + , methylamine ion); the metal cation includes Cs + (cesium ion) and Rb + (rubidium ion); the divalent metal cation includes Pb 2+ (lead ions) and Sn 2+ (tin ion); the halogen anion includes I - (iodide ion), Br - (bromide ion), Cl - (chloride ion); the components of the material of the 3D perovskite layer specifically include but are not limited to MAPbBr3 (methylamine lead bromide) or MAPbI3 (methylamine lead iodine).

[0042] Furthermore, the composition structure of the material of the 2D perovskite layer is R m A n-1 B n X 3n+1 , where A is a monovalent cation, B is a divalent metal cation, X is a halogen anion, and R is [BX6] 4- The bulky organic spacer cations between the octahedral layers, n is the number of stacked layers of inorganic perovskite layers between the spacer layers, and m is used to determine the type of 2D perovskite. m = 1 is DJ (Dion-Jacobson) type 2D perovskite, and m = 2 is RP (Ruddlesden-Popper) type 2D perovskite. The bulky organic spacer cations refer to the bulky organic spacer cations compared to MA. + or FA + The organic spacer cation with a larger volume, specifically, the organic spacer cation with a larger volume refers to an organic spacer cation with an ion radius greater than 0.28 nanometers.

[0043] In some embodiments, the 2D perovskite material comprises PEA2PbBr4 (phenylethylamine lead bromide), OA2PbBr4 (octylamine lead bromide), BA2PbBr4 (butylamine lead bromide), EA2PbBr4 (ethylamine lead bromide), PEA2PbI4 (phenylethylamine lead iodine), HA2PbI4 (hexylamine lead iodine), BA2PbI4 (butylamine lead iodine), or BA2MAPb2I7 (butylamine 2-methylamine lead 2-iodine 7). The halide ions in the 2D perovskite layer and the 3D perovskite layer can be the same or different. For example, 2D perovskite is formed in situ on the surface of a 3D perovskite by amine vapor fumigation. In this case, the halide ions in the 2D and 3D perovskite layers are the same, and can both be bromide ions or iodide ions. However, other methods can be used to prepare 2D and 3D perovskite layers with different halide ions to form a perovskite heterojunction and a bandpass photodetector. The B cation combines with six adjacent X anions to form [BX6] 4- Octahedron, these [BX6] 4- The octahedrons form a periodic array by sharing vertices. The organic spacer layer is formed by introducing large organic spacer cations into the three-dimensional perovskite to form a periodic array of metal halide octahedrons[BX6]. 4- The layer is formed by stretching along a specific crystal plane (such as (100) crystal plane, (110) crystal plane, (111) crystal plane). Large-volume organic spacer cations refer to those that are larger than MA. + or FA + Larger organic spacer cations. Organic spacer layers alternate with octahedral inorganic layers to form layered perovskites.

[0044] Furthermore, the thickness of the 2D perovskite layer 11 is determined according to the absorption coefficient of the material of the 2D perovskite layer 11 and Beer-Lambert's law, so as to filter out excitation light with a wavelength shorter than a preset starting wavelength.

[0045] In some embodiments, the successful preparation of 2D / 3D perovskite heterojunctions and bandpass photodetectors often requires facing challenges such as interface holes, defects, and ion exchange between the two material phases. In previous studies, 2D perovskites mainly played a defect passivation role to achieve full spectrum response, and it was not thought that they could be used as a short-wavelength light filter layer to achieve a bandpass effect; Beer-Lambert's law describes the relationship between the amount of light absorbed by a substance at a specific wavelength and the distance the light passes through the substance. As the distance increases, the intensity of the transmitted light decreases exponentially. The mathematical expression of Beer-Lambert's law is I(λ)=I0(λ)e -αdWherein, I0(λ) is the intensity of incident light of wavelength λ, α is the absorption coefficient of the material for light of that wavelength, d is the thickness of the material, and I(λ) is the intensity of the transmitted light of that wavelength. Furthermore, the thickness of the 2D perovskite layer is greater than or equal to 1 micron, and the thickness of the 3D perovskite layer is greater than or equal to 500 nanometers. Preferably, the thickness of the 2D perovskite layer is 2 to 3 microns.

[0046] In some embodiments, the thickness of the 2D perovskite layer can be 1 micron, 2 microns, 3 microns, 4 microns, 5 microns, 6 microns, 7 microns, 8 microns, 9 microns, 10 microns, and so on. The surface of a 3D perovskite layer typically contains a high density of defects. Due to surface charge quenching, the device's external quantum efficiency (EQE) is narrowband. When a very thin layer of 2D perovskite (e.g., less than 1 micron thick) covers the surface of the 3D perovskite layer, this thin layer of 2D perovskite acts as a passivation layer for the surface defects and fails to function as a light filter. Under the action of this thin layer of 2D perovskite, the surface defects of the 3D perovskite are passivated by the 2D perovskite, and the device's EQE shifts from narrowband to broadband. Only when the 2D perovskite layer is thicker (e.g., greater than or equal to 1 micron) can it function as a light filter, transforming the device into a bandpass photodetector. The response onset edge (predetermined onset wavelength) of this bandpass device is primarily determined by the composition of the 2D perovskite layer. The end edge (preset cutoff wavelength) of the bandpass photodetector is determined by the material of the 3D perovskite layer. Preferably, the thickness of the 2D perovskite layer is 2 to 3 microns. When the thickness of the 2D perovskite layer is 2 to 3 microns, it can act as a stable light filter.

[0047] Preferably, the different compositions (or components) and thicknesses of the 2D perovskite layer correspond to different bandpass wavelength ranges of the excitation light, so that the (2D / 3D) perovskite heterojunction (photoelectric) detector can accurately identify the excitation light within the wavelength range of the low-loss "blue window" (such as 400±50 nanometers) of seawater or the low-loss window "green window" (such as 500-550 nanometers) of river water, with an interval of preset wavelength interval, where the preset wavelength interval is preferably 20 to 25 nanometers.

[0048] In the prior art, 2D / 3D perovskite heterostructures are often used to improve device efficiency and stability in the field of perovskite photovoltaics. Specifically, 3D perovskites are used to absorb light energy, and 2D perovskites are used to passivate surface defects of 3D perovskites to absorb the full spectrum as much as possible and convert solar energy (light energy) into electrical energy. In an embodiment of the present invention, the inventors creatively discovered that if the thickness of the 2D perovskite layer reaches a certain thickness, the 2D perovskite layer and the 3D perovskite layer can constitute a bandpass detector, and by adjusting the composition and / or thickness of the 2D perovskite, it can be used to identify different wavelengths of excitation light. Based on this, the inventors creatively used 2D / 3D perovskite heterostructures to constitute a bandpass detector for underwater optical communication. Since underwater communication is affected by water quality and the environment is unstable, the inventors could not predict the technical effects of the embodiments of the present invention in advance. However, the inventors overcame the problem of unpredictable technical effects, realized the formation of a bandpass detector using a 2D / 3D perovskite heterostructure, and conducted verification to confirm the effects of the embodiments of the present invention. By covering the surface of the 3D perovskite with a layer of 2D perovskite of a preset thickness, the short-wavelength components in the excitation light are filtered out, and the sensitive wavelength range of the resulting 2D / 3D perovskite heterojunction detector is limited to the blue window band and the green window band, where the blue window band is 400±50nm (nanometers) and the green window band is 525±25nm.

[0049] The embodiments of the present invention have the following technical effects: By adjusting the thickness of the 2D perovskite, the 2D perovskite and 3D perovskite form a 2D / 3D perovskite heterojunction bandpass photodetector with a specified bandpass, which can recognize excitation light of a specified center wavelength, thereby enabling wavelength-modulated underwater optical communication. Compared to conventional intensity-modulated optical communication, wavelength modulation has the advantage of being insensitive to changes in the underwater light propagation path, resulting in a low bit error rate and enabling beyond-line-of-sight communication. Specifically, by adjusting the optical absorption edges of the 2D and 3D perovskite, the response onset and cutoff edges of the 2D / 3D perovskite heterojunction bandpass photodetector can be finely controlled, enabling the 2D / 3D perovskite heterojunction (photodetector) assembly to accurately recognize optical signals within the wavelength range of the low-loss "blue window" (e.g., 400±50nm) for seawater or the low-loss "green window" (e.g., 525±25nm) for river water, with wavelength intervals of 20 to 30nm. This enables wavelength-modulated underwater optical communication. Compared with common intensity-modulated optical communications, the advantage of wavelength modulation is that the wavelength is insensitive to changes in the underwater light propagation path, so the bit error rate is low and beyond-line-of-sight communication can be achieved.

[0050] Second, as Figure 2 As shown, an embodiment of the present invention provides an underwater optical communication component based on a perovskite heterojunction detector, comprising: at least one perovskite heterojunction detector group 21;

[0051] Each perovskite heterojunction detector group 21 includes at least one perovskite heterojunction detector 22 as described above;

[0052] All perovskite heterojunction detectors 22 are arranged in a preset arrangement pattern;

[0053] The perovskite heterojunction detectors 22 in the same perovskite heterojunction detector group 21 have the same preset starting wavelength, and the perovskite heterojunction detectors 22 in different perovskite heterojunction detector groups 21 have different preset starting wavelengths.

[0054] In some embodiments, adding (2D / 3D) perovskite heterojunction detector groups can increase the number of codes and improve optical communication efficiency. Increasing the number of (2D / 3D) perovskite heterojunction detectors in each (2D / 3D) perovskite heterojunction detector group can enhance the amplitude of the electrical signal converted from the received signal. The perovskite heterojunction detectors in each perovskite heterojunction detector group can be arranged in the same or different patterns, with various arrangements available, tailored to the specific application environment for optimal reception of excitation light. For example, these arrangements include, but are not limited to, in-plane matrix arrangements and hemispherical arrangements. The response wavelength range of the perovskite heterojunction bandpass photodetector is determined by the composition and / or thickness of the 2D and 3D perovskite layers. The different materials and / or thicknesses of the 2D perovskite layer of the perovskite heterojunction (photoelectric) detector correspond to different bandpass wavelength ranges of the excitation light, so that the perovskite heterojunction (photoelectric) detector can accurately identify light signals within the wavelength range of the low-loss "blue window" (such as 400±50nm) of seawater or the low-loss "green window" (such as 500-550nm) of river water, with a preset wavelength interval, wherein the preset wavelength interval is preferably 20-30nm. The preset arrangement mode includes but is not limited to arranging all perovskite heterojunction detectors in a matrix form on a flat plate, arranging all perovskite heterojunction detectors evenly on a curved surface, etc.; by using multiple perovskite heterojunction detectors with the same excitation light bandpass range, the response signal intensity of the excitation light corresponding to the central wavelength can be enhanced, which is convenient for subsequent sampling and detection. Considering the cost and volume, etc., it is preferred that each perovskite heterojunction detector group has only one perovskite heterojunction detector. Multiple perovskite heterojunction detectors can share a 3D perovskite layer, such as Figure 6 As shown, the four perovskite heterojunction detectors, namely detector 1, detector 2, detector 3 and detector 4, share a 3D perovskite layer; each perovskite heterojunction detector can also have its own independent 2D perovskite layer and 3D perovskite layer.

[0055] Multiple target center wavelengths can be determined in the blue window or the green window at preset wavelength intervals, and the same number of perovskite heterojunction detector groups as the multiple target center wavelengths can be produced. By adjusting the composition and / or thickness of the 2D perovskite layer, the perovskite heterojunction detectors in each perovskite heterojunction detector group respond to the excitation light of the same target center wavelength, and the multiple perovskite heterojunction detector groups correspond to multiple target center wavelengths one by one. The excitation light source can emit light signals of multiple target center wavelengths, and a coding relationship can be defined between whether the light signal (excitation light) of the target center wavelength is detected and a binary number. Thus, the wavelength of the excitation light received by the perovskite heterojunction detector and the predefined coding relationship can be used to restore the communication data to be sent by the excitation light transmitter. Figure 5 As shown, there are four perovskite heterojunction detector groups, and each perovskite heterojunction detector group has one perovskite heterojunction detector, so Figure 5 The response starting edge (preset starting wavelength) and response cutoff edge (preset cutoff wavelength) of each of the four perovskite heterojunction detectors are given in the figure. Figure 5 The four perovskite heterojunction detectors are (perovskite heterojunction) detector S1, (perovskite heterojunction) detector S2, (perovskite heterojunction) detector S3 and (perovskite heterojunction) detector S4. The response cutoff edges of the four detectors are the same, but the response starting edges are different. The response starting edges of the four detectors correspond to the first response starting edge 51, the second response starting edge 52, the third response starting edge 53 and the fourth response starting edge 54, respectively. Figure 5 When the central wavelength of the excitation light is between the first response starting edge 51 and the second response starting edge 52, only the (perovskite heterojunction) detector corresponding to the first response starting edge 51 has a response output. When the central wavelength of the excitation light is between the second response starting edge 52 and the third response starting edge 53, the (perovskite heterojunction) detectors corresponding to the first response starting edge 51 and the second response starting edge 52 all have a response output. When the central wavelength of the excitation light is between the third response starting edge 53 and the fourth response starting edge 54, the (perovskite heterojunction) detectors corresponding to the first response starting edge 51, the second response starting edge 52, and the third response starting edge 53 all have a response output. When the central wavelength of the excitation light is to the right of the fourth response starting edge 54, the detectors corresponding to the first response starting edge 51, the second response starting edge 52, the third response starting edge 53, and the fourth response starting edge 54 all have a response output. Based on the above characteristics, the above response outputs can be directly used or the above response outputs can be differentiated to obtain a differential result, and a truth table can be constructed between the response outputs or the differential result and the binary numbers 0 and 1, and the encoding relationship can be determined based on the truth table. exist Figure 5 In the example, the preset starting wavelengths of the perovskite heterojunction detectors are different, and the preset cutoff wavelengths are basically the same. Figure 5The passband wavelength ranges of the four perovskite heterojunction detectors shown. For example, the four perovskite heterojunction detectors are detector S1, detector S2, detector S3, and detector S4 respectively. The relationship of the four wavelengths detected respectively is L1 < L2 < L3 < L4. When electrical signals are detected in all of detector S1, detector S2, detector S3, and detector S4, it is considered that the excitation light with wavelength L4 must have appeared, but it cannot be determined whether the excitation lights with wavelengths L1, L2, and L3 have appeared. When electrical signals are detected in detector S1, S2, and S3, and no electrical signal is detected in S4, it is considered that the excitation light with wavelength L3 must have appeared, and the excitation light with wavelength L4 must not have appeared, but it cannot be determined whether the excitation lights with wavelengths L1 and L2 have appeared. And so on. The binary codes corresponding to the excitation lights detected by the four perovskite heterojunction detectors can be that L1 corresponds to the binary number 00, L2 corresponds to the binary number 01, L3 corresponds to the binary number 10, and L4 corresponds to the binary number 11. The advantage is that the perovskite heterojunction detectors are multiplexed. For the detection of the excitation lights with wavelengths L2, L3, and L4, 2, 3, and 4 perovskite heterojunction detectors detect simultaneously respectively. The signal amplitude is high, the accuracy is high, and the perovskite heterojunction detector with a fault can be found in time. For example, based on Figure 5 Regarding the relationship of the passband wavelength ranges of the four perovskite heterojunction detectors, if the perovskite heterojunction detector for detecting the long-wavelength excitation light has a signal, then the perovskite heterojunction detector for detecting the short-wavelength excitation light must have a signal. If there are signals in perovskite heterojunction detectors S1 and S3, and no signal in S2, then it is very likely that the perovskite heterojunction detector S2 is damaged. In a specific implementation, the preset starting wavelength (i.e., the starting edge of the response) of each perovskite heterojunction detector can also be controlled by regulating the material and / or thickness of the 2D perovskite layer, and the preset cut-off wavelength (i.e., the cut-off edge of the response) of each perovskite heterojunction detector can be controlled by regulating the material and / or thickness of the 3D perovskite layer, so that the passband wavelength ranges of each perovskite heterojunction detector group overlap or do not overlap with each other to meet specific application requirements or the requirements for mapping with binary codes. When the passband wavelength ranges of each perovskite heterojunction detector group do not overlap, each perovskite heterojunction detector group will not be affected by the excitation lights of other perovskite heterojunction detector groups, so a parallel transmission channel can be constructed to improve the transmission efficiency.

[0056] The embodiments of the present invention have the following technical effects: Using at least one perovskite heterojunction detector group to form an underwater optical communication component, so as to identify and detect the excitation lights of multiple central wavelengths through the optical communication component, thereby realizing wavelength modulation underwater optical communication. Compared with common intensity modulation optical communication, the advantage of wavelength modulation is that the wavelength is insensitive to the change of the underwater optical propagation path, so the bit error rate is low and ultra-long-distance communication can be achieved.

[0057] In the third aspect, as Figure 3As shown, an embodiment of the present invention provides an underwater optical communication system based on a perovskite heterojunction detector, comprising:

[0058] The underwater optical communication component 30 based on the perovskite heterojunction detector, the excitation light emitting device 31, and the control and acquisition system 32 for collecting the electrical signal output by the underwater optical communication component as described above;

[0059] The excitation light emitting device 31 is used to modulate communication data into excitation light consisting of light of at least one central wavelength according to a preset communication protocol, and emit the excitation light;

[0060] The underwater optical communication component 30 is used to receive the excitation light and output an electrical signal corresponding to the excitation light;

[0061] The control and acquisition system 32 is used to collect the electrical signal corresponding to the excitation light and convert the electrical signal into the communication data.

[0062] Furthermore, the control and acquisition system 32 includes: a controller 321 and a differential identification unit 322;

[0063] The differential identification unit 322 is used to receive the electrical signal corresponding to the excitation light and generate a differential signal;

[0064] The controller 321 is configured to sample the differential signal and convert the differential signal into communication data.

[0065] Fourthly, Figure 4 As shown, an embodiment of the present invention provides an underwater optical communication method based on a perovskite heterojunction detector, comprising:

[0066] Step S40, the excitation light emitting device modulates the communication data into excitation light consisting of light of at least one central wavelength according to a preset communication protocol, and emits the excitation light;

[0067] Step S41, the underwater optical communication component based on the perovskite heterojunction detector as described above receives the excitation light and outputs an electrical signal corresponding to the excitation light;

[0068] Step S42: Control the acquisition system to acquire the electrical signal corresponding to the excitation light, and convert the electrical signal into the communication data.

[0069] Furthermore, the control acquisition system includes: a controller and a differential identification unit;

[0070] The differential recognition unit receives the electrical signal corresponding to the excitation light and generates a differential signal;

[0071] The controller samples the differential signal and converts the differential signal into communication data.

[0072] The above technical solutions of the embodiments of the present invention are described in detail below with reference to specific application examples. For technical details not introduced during the implementation process, please refer to the relevant description above.

[0073] The present invention relates to the field of perovskite photodetectors, specifically using a set of (2D / 3D) perovskite heterojunction detectors to implement wavelength-modulated underwater optical communications (i.e., the light source consists of multiple optical signals of different wavelengths, with each wavelength representing one binary bit). Compared to conventional intensity-modulated optical communications, wavelength modulation offers the advantage of being insensitive to changes in the underwater light propagation path, resulting in a low bit error rate and enabling beyond-line-of-sight communications.

[0074] The purpose of the embodiments of the present invention is to develop an underwater optical communication component with wavelength resolution capability using a group of 2D / 3D perovskite heterojunction detectors with different wavelength response ranges, which is used to realize the detection of underwater wavelength modulated optical signals and the transmission of information.

[0075] The 2D / 3D perovskite heterojunction detector used in the embodiment of the present invention is a type of photodetector. By combining 2D perovskite materials and 3D perovskite materials of different components (ingredients) / thicknesses, its response wavelength range can be adjusted. This type of detector can be either a broadband photodetector or a bandpass / narrowband photodetector. In principle, stacking organic dyes at the front end of the photodetector can also achieve bandpass detection, but the absorption edge of the organic dye changes slowly, which is not conducive to forming a steep wavelength switching characteristic. In the 2D / 3D perovskite heterojunction (photo) detector used in the embodiment of the present invention, the response starting edge and cutoff edge of the device are flexibly adjustable and steep enough, so that effective resolution of multiple wavelengths can be achieved within the limited underwater optical communication wavelength range (for example, the "blue window" of 400±50nm in seawater and the "green window" of 525±25nm in river water).

[0076] The wavelength response range of the 2D / 3D perovskite heterojunction (photoelectric) detector used in the embodiment of the present invention can be precisely adjusted, that is, its response starting edge and response cutoff edge can be flexibly adjusted. Figure 5 As shown, the steep optical absorption edges of 2D perovskites and 3D perovskites can ensure that the 2D / 3D perovskite heterojunction bandpass photodetectors have sharp response onset and response cutoff edges, as well as low spectral crosstalk.

[0077] The embodiment of the present invention utilizes the differential working mode of a group of 2D / 3D perovskite heterojunction (photoelectric) detectors to realize wavelength-modulated underwater optical communication. First, a group of detectors with a suitable wavelength response range is selected from a series of 2D / 3D perovskite heterojunction (photoelectric) detectors that respond to different wavelength ranges. Then, these detectors are integrated into a unit (underwater optical communication component) and used in combination. The integrated unit (underwater optical communication component) can detect and identify optical signals with a wavelength interval of 20 to 30 nm (for example, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30 nanometers) in a narrow underwater low-loss "blue window" (for example, 400±50 nm) or "green window" (for example, 525±25 nm). Since the response edge of the photodetector based on 2D / 3D perovskite heterojunction (2D / 3D perovskite heterojunction detector) is very sharp, the spectral crosstalk caused by the light signal with a wavelength in the cutoff region near its response edge is very small and the bit error rate is low, it is bound to have important application prospects in the field of underwater optical communications in the future.

[0078] The manufacturing steps of the 2D / 3D perovskite heterojunction (photoelectric) detector assembly (underwater optical communication assembly) in the embodiment of the present invention include:

[0079] 1) Preparation of 3D perovskite single crystals or thin films to serve as the photoactive layer;

[0080] 2) Covering the surface of the 3D perovskite film obtained in step 1) with a layer of 2D perovskite to form a 2D / 3D perovskite heterojunction structure, and a series of different 2D / 3D perovskite heterojunctions can be obtained by adjusting the chemical composition of the 2D perovskite and the 3D perovskite (including but not limited to organic cations, metal cations, and halogen anion components);

[0081] 3) Fabricating the multiple 2D / 3D perovskite heterojunctions obtained in step 2) into photodetectors (including but not limited to post-processing the upper and lower surfaces, preparing electron / hole transport layers, and evaporating metal electrodes). The active operating area of ​​the detector is defined by the mask used.

[0082] 4) Integrate multiple 2D / 3D perovskite heterojunction (photoelectric) detectors onto a perovskite single crystal / thin film sample to form a functional unit, and use it with external circuits (including but not limited to microcontrollers, power modules, light source modules, differential circuits, signal amplification circuits, etc.) to achieve wavelength-modulated underwater optical communication.

[0083] The principles of the embodiments of the present invention are described below.

[0084] The "blue window" and "green window" have longer penetration distances in pure seawater and seawater / river water containing algae, respectively, and are the most suitable wavelength ranges for optical signal sources for underwater wireless optical communications. By integrating multiple 2D / 3D perovskite heterojunction (photoelectric) detectors with different wavelength response ranges into a functional unit (underwater optical communication component), combined with external circuits, underwater optical communication can be achieved in the "blue window" or "green window". The working principle is as follows:

[0085] For underwater optical detection in pure seawater with low levels of suspended particles and organic matter, the response onset and / or cutoff of a 2D / 3D perovskite heterojunction bandpass photodetector can be finely tuned within the "blue window" (e.g., the 400±50nm wavelength range). Combining multiple 2D / 3D perovskite heterojunction bandpass photodetectors, or combining or integrating a 2D / 3D perovskite heterojunction (or 3D perovskite) broadband photodetector with multiple 2D / 3D perovskite heterojunction bandpass photodetectors on a single panel, effectively resolves wavelength-modulated optical signals within a 400±50nm wavelength range and with intervals of 20-30nm. Similarly, for underwater optical detection in seawater with high levels of suspended particles and organic matter, the response onset of a 2D / 3D perovskite heterojunction bandpass photodetector can be finely tuned within the "green window" (e.g., the 525±25nm wavelength range). Combining or integrating multiple photodetectors on a single panel effectively resolves wavelength-modulated optical signals within this range.

[0086] Due to the steep optical absorption edge of 2D perovskites, the photodetectors in this group exhibit excellent resistance to optical crosstalk. Each individual photodetector in the group outputs a distinct electrical signal in response to the wavelength-modulated light signal, which is used to determine the excitation wavelength. Simultaneously, these electrical signals are differentially calculated to detect and identify the wavelength-modulated light signal, enabling rapid underwater information transmission.

[0087] Figure 7 Four central wavelengths of excitation light are given, namely the first excitation light, the second excitation light, the third excitation light and the fourth excitation light, and the emission spectra of four LED light sources (excitation light) with central wavelengths of 374nm (first excitation light central wavelength 71), 400nm (second excitation light central wavelength 72), 428nm ((third excitation light central wavelength 73)) and 450nm ((fourth excitation light central wavelength 74)) respectively. Figure 7 There are 6 sub-graphs from top to bottom in the image. Figure 7 It is shown in Figure 2, which makes it easier and clearer to observe the characteristics of the detector at different wavelengths and in different measurement environments. Figure 7The first upper sub-figure shows the position of the central wavelengths of the four excitation lights, and the second upper sub-figure shows the absorption coefficients of the four central wavelengths in river water and sea water. It can be seen that the absorption coefficients of the four central wavelengths in sea water and river water are at a low level relative to the entire wavelength range; the third to sixth upper sub-figures, i.e. the bottom four figures, are the normalized external quantum efficiency spectra (EQE spectra) of four 2D / 3D perovskite heterojunction bandpass photodetectors based on 3D perovskite MAPbBr3, namely PEA2PbBr4 / MAPbBr3, OA2PbBr4 / MAPbBr3, BA2PbBr4 / MAPbBr3 and EA2PbBr4 / MAPbBr3, where the thickness of PEA2PbBr4 is about 10nm, and the thickness of OA2PbBr4, BA2PbBr4 and EA2PbBr4 is about 2-3μm. Figure 7 The third to sixth sub-figures in the upper part of the figure give the positional relationship between the bandpass wavelength ranges of the four sensors (the first bandpass wavelength range 711, the second bandpass wavelength range 721, the third bandpass wavelength range 731 and the fourth bandpass wavelength range 741) and the four center wavelengths. The first excitation light center wavelength 71 is located between the response starting edge of the first bandpass wavelength range 711 and the response starting edge of the second bandpass wavelength range 721, the second excitation light center wavelength 72 is located between the response starting edge of the second bandpass wavelength range 721 and the response starting edge of the third bandpass wavelength range 731, the third excitation light center wavelength 73 is located between the response starting edge of the third bandpass wavelength range 731 and the response starting edge of the fourth bandpass wavelength range 741, and the fourth excitation light center wavelength 74 is located to the right of the response starting edge of the fourth bandpass wavelength range 741. Figure 7 The four central wavelengths of excitation light are located in the underwater low-loss window (400±50nm), with minimal light attenuation, making it an ideal light source for underwater wireless optical communications.

[0088] Figure 8 The photocurrent responses of four 2D / 3D perovskite heterojunction bandpass photodetectors are demonstrated under illumination by LED light pulses of four different central wavelengths and an external bias of +8 V. When the devices operate in differential mode, the information carried by the incident light of these four different central wavelengths can be captured.

[0089] Figure 9The EQE spectra of four 2D / 3D perovskite heterojunction devices based on the 3D perovskite MAPbI3 are presented: PEA2PbI4 / MAPbI3, HA2PbI4 / MAPbI3, BA2PbI4 / MAPbI3, and BA2MAPb2I7 / MAPbI3. PEA2PbI4 has a thickness of approximately 10 nm, while HA2PbI4, BA2PbI4, and BA2MAPb2I7 have thicknesses of approximately 2-3 μm. The response onset of this group of devices is finely tuned within the "green window" wavelength range, enabling wavelength-modulated underwater optical communications in seawater or lake water containing algae.

[0090] The embodiments of the present invention have the following technical effects:

[0091] The differential operating mode of a set of 2D / 3D perovskite heterojunction detectors prepared in an embodiment of the present invention can realize wavelength-modulated underwater optical communication. The set of 2D / 3D perovskite heterojunction bandpass detectors used can identify wavelength-modulated optical signals with an interval of 20 to 30 nm, which is conducive to using more wavelength light sources for simultaneous communication in the narrow underwater "blue-green window" and fast information transmission speed. Compared with common intensity-modulated optical communication, the wavelength-modulated optical communication method realized has a low bit error rate and can achieve beyond-line-of-sight communication because the wavelength is insensitive to changes in the underwater light propagation path.

[0092] The following is another example of an embodiment in which a group of 2D / 3D perovskite heterojunction (photoelectric) detectors are integrated and used in combination. Figure 6As shown, the structure of a single detector is Au electrode / 2D perovskite / 3D perovskite / Au electrode (gold electrode). The embodiments of the present invention finely control the response starting edge of 2D / 3D perovskite heterojunction (photoelectric) detectors through component engineering, enabling optical communication in the low-loss "blue window" and "green window" underwater. The embodiments of the present invention combine multiple 2D / 3D perovskite heterojunction bandpass photodetectors or 2D / 3D perovskite heterojunction broadband photodetectors, utilizing their differential operating modes to achieve wavelength-modulated underwater optical communication. Multiple 2D / 3D perovskite heterojunctions are fabricated into photodetectors. The response starting edge of this group of photodetectors is finely tuned within the wavelength range of the underwater "blue window" or "green window." The multiple photodetectors and other required circuit modules are integrated into a system and applied to wavelength-modulated underwater optical communication. The embodiments of the present invention utilize the differential operating modes of multiple 2D / 3D perovskite heterojunction (photoelectric) detectors to achieve wavelength-modulated underwater optical communication. The embodiment of the present invention fine-tunes the response starting edge and cutoff edge of the 2D / 3D perovskite heterojunction bandpass optical detector by adjusting the optical absorption edge of 2D perovskite and 3D perovskite, so that the 2D / 3D perovskite heterojunction (photoelectric) detector assembly can accurately identify optical signals within the wavelength range of the underwater low-loss "blue window" (such as 400±50nm) or "green window" (such as 500-550nm) with an interval of 20 to 30nm. At the same time, underwater optical communication simulation experiments have confirmed that a group of optical detectors based on 2D / 3D perovskite heterojunctions can effectively identify a group of multi-wavelength excitation light signals, thereby realizing wavelength-modulated underwater optical communication. Compared with common intensity-modulated optical communication, the advantage of wavelength modulation is that the wavelength is not sensitive to changes in the underwater light propagation path, so the bit error rate is low and beyond-line-of-sight communication can be achieved.

[0093] The following is an embodiment of a method for implementing wavelength-modulated underwater optical communication by using a differential operating mode of a group of 2D / 3D perovskite heterojunction bandpass detectors, specifically comprising the following steps:

[0094] 1. Fabricating four 2D / 3D perovskite heterojunctions into photodetectors:

[0095] Au electrodes were vacuum-deposited on the upper and lower surfaces of four 2D / 3D perovskite heterojunctions, namely PEA2PbBr4 / MAPbBr3, OA2PbBr4 / MAPbBr3, BA2PbBr4 / MAPbBr3 and EA2PbBr4 / MAPbBr3, to prepare devices with the structure of Au (15 nm) / 2D perovskite / 3D perovskite / Au, where the effective working area of ​​the device was defined by the mask used for evaporation.

[0096] 2. Prepare a glass tank filled with water, place four 2D / 3D perovskite heterojunction (photoelectric) detectors on a panel and place it on one side of the tank, then use 374nm (nanometer), 400nm, 428nm and 450nm LED light sources on the other side of the tank to illuminate the group of devices in chronological order, and use an oscilloscope to record the electrical signals generated by the devices. The results are as follows Figure 8 shown.

[0097] Depend on Figure 8 It can be seen that when the central wavelength of the excitation light is 374nm, only the photodetector based on the PEA2PbBr4 / MAPbBr3 perovskite heterojunction has a photoelectric response; when the central wavelength of the excitation light is 400nm, the photodetectors based on the PEA2PbBr4 / MAPbBr3 and OA2PbBr4 / MAPbBr3 perovskite heterojunctions have a photoelectric response; when the central wavelength of the excitation light is 428nm, the photodetectors based on the PEA2PbBr4 / MAPbBr3, OA2PbBr4 / MAPbBr3 and BA2PbBr4 / MAPbBr3 perovskite heterojunctions have a photoelectric response; when the central wavelength of the excitation light is 450nm, the photodetectors based on the PEA2PbBr4 / MAPbBr3, OA2PbBr4 / MAPbBr3, BA2PbBr4 / MAPbBr3 and EA2PbBr4 / MAPbBr3 perovskite heterojunctions all have a photoelectric response. That is, the light detection component obtains different signals under different excitation light irradiation, and can effectively detect and identify multi-wavelength excitation light signals in the range of 400±50nm underwater.

[0098] It should be understood that the specific order or hierarchy of steps in the disclosed processes is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0099] In the foregoing detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that embodiments of the claimed subject matter require more features than are expressly recited in each claim. On the contrary, as reflected in the appended claims, the invention comprises less than all the features of any individual disclosed embodiment. The appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0100] The above description of the disclosed embodiments is intended to enable any person skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments presented herein but is intended to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0101] The foregoing description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purposes of describing the above embodiments, but one of ordinary skill in the art will recognize that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to encompass all such changes, modifications and variations that fall within the scope of the appended claims. Furthermore, to the extent the term "comprising" is used in the specification or claims, the term is intended to be encompassed in a manner similar to the term "including," as explained in terms of "including," used as a transitional word in the claims. Furthermore, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or."

[0102] Those skilled in the art will also appreciate that the various illustrative logical blocks, units, and steps listed in the embodiments of the present invention can be implemented by electronic hardware, computer software, or a combination of the two. To clearly demonstrate the interchangeability of hardware and software, the various illustrative components, units, and steps described above have generally described their functions. Whether such functions are implemented by hardware or software depends on the specific application and the design requirements of the entire system. Those skilled in the art may use various methods to implement the described functions for each specific application, but such implementation should not be understood as exceeding the scope of protection of the embodiments of the present invention.

[0103] The various illustrative logic blocks or units described in the embodiments of the present invention can be implemented or operated by a general-purpose processor, a digital signal processor, an application-specific integrated circuit (ASIC), a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. The general-purpose processor can be a microprocessor, and optionally, the general-purpose processor can also be any conventional processor, controller, microcontroller or state machine. The processor can also be implemented by a combination of computing devices, such as a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a digital signal processor core, or any other similar configuration.

[0104] The steps of the methods or algorithms described in the embodiments of the present invention may be directly embedded in hardware, a software module executed by a processor, or a combination of the two. The software module may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. For example, the storage medium may be connected to the processor so that the processor can read information from the storage medium and write information to the storage medium. Alternatively, the storage medium may also be integrated into the processor. The processor and storage medium may be provided in an ASIC, which may be provided in a user terminal. Alternatively, the processor and storage medium may also be provided in different components in the user terminal.

[0105] In one or more exemplary designs, the above-mentioned functions described in the embodiments of the present invention can be implemented in hardware, software, firmware, or any combination of the three. If implemented in software, these functions can be stored on a computer-readable medium or transmitted in the form of one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media that facilitate the transfer of computer programs from one place to another. Storage media can be any available medium that can be accessed by a general or special computer. For example, such computer-readable media can include but are not limited to RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store program code in the form of instructions or data structures and other forms that can be read by general or special computers, or general or special processors. In addition, any connection can be appropriately defined as a computer-readable medium. For example, if the software is transmitted from a website, server or other remote resource via a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless methods such as infrared, wireless and microwave, it is also included in the definition of computer-readable media. The disks and discs mentioned above include compact disks, laser disks, optical disks, DVDs, floppy disks, and Blu-ray discs. Disks typically reproduce data magnetically, while discs typically reproduce data optically with lasers. Combinations of the above may also be included in computer-readable media.

[0106] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An underwater optical communication component based on a perovskite heterojunction detector, characterized in that: include: At least one perovskite heterojunction detector group (21); each perovskite heterojunction detector group (21) includes at least one perovskite heterojunction detector (22); All perovskite heterojunction detectors (22) are arranged in a preset arrangement pattern; The perovskite heterojunction detectors (22) within the same perovskite heterojunction detector group (21) have the same preset starting wavelength, and the perovskite heterojunction detectors (22) between different perovskite heterojunction detector groups (21) have different preset starting wavelengths; The perovskite heterojunction detector comprises: a 3D perovskite layer (12), a 2D perovskite layer (11) covering the upper surface of the 3D perovskite layer (12), a first electrode layer (10) covering the upper surface of the 2D perovskite layer (11), and a second electrode layer (13) covering the lower surface of the 3D perovskite layer; The band gap of the material of the 2D perovskite layer (11) is greater than the band gap of the material of the 3D perovskite layer (12), the exciton binding energy of the material of the 2D perovskite layer (11) is greater than the exciton binding energy of the material of the 3D perovskite layer (12), the thickness of the 2D perovskite layer (11) is a first preset thickness, and the thickness of the 3D perovskite layer is a second preset thickness, so that the perovskite heterojunction detector generates an electrical signal response to excitation light greater than or equal to a preset starting wavelength and less than or equal to a preset cut-off wavelength, and does not generate an electrical signal response to excitation light less than the preset starting wavelength or greater than the preset cut-off wavelength; the preset starting wavelength is determined by the material of the 2D perovskite layer (11) and the first preset thickness, and the preset cut-off wavelength is determined by the material of the 3D perovskite layer (12) and the second preset thickness.

2. The perovskite heterojunction detector according to claim 1, wherein: The composition structure of the material of the 3D perovskite layer is ABX3, wherein A is a monovalent cation, B is a divalent metal cation, and X is a halogen anion.

3. The perovskite heterojunction detector according to claim 1, wherein: The composition structure of the material of the 2D perovskite layer is R m A n-1 B n X 3n+1 , where A is a monovalent cation, B is a divalent metal cation, X is a halogen anion, and R is [BX6] 4- Bulk organic spacer cations between the octahedral layers, n is the number of stacked inorganic perovskite layers between the spacer layers, m For determining the type of 2D perovskite, m =1 is DJ-type 2D perovskite, m =2 is RP-type 2D perovskite.

4. The perovskite heterojunction detector according to claim 3, wherein: The thickness of the 2D perovskite layer is determined according to the absorption coefficient of the 2D perovskite layer material and the Beer-Lambert law to filter out excitation light with a wavelength shorter than a preset starting wavelength.

5. The perovskite heterojunction detector according to claim 1, wherein: The thickness of the 2D perovskite layer is greater than or equal to 2 micrometers, and the thickness of the 3D perovskite layer is greater than or equal to 500 nanometers.

6. An underwater optical communication system based on a perovskite heterojunction detector, characterized in that: include: An underwater optical communication component (30) based on a perovskite heterojunction detector according to claim 1, an excitation light emitting device (31), and a control and acquisition system (32) for acquiring electrical signals output by the underwater optical communication component; The excitation light emitting device is used to modulate communication data into excitation light consisting of light of at least one central wavelength according to a preset communication protocol, and emit the excitation light; The underwater optical communication component (30) is used to receive the excitation light and output an electrical signal corresponding to the excitation light; The control and acquisition system (32) is used to acquire the electrical signal corresponding to the excitation light and convert the electrical signal into the communication data.

7. The underwater optical communication system based on perovskite heterojunction detector according to claim 6, characterized in that: The control acquisition system (32) includes: a controller (321) and a differential identification unit (322); The differential identification unit (322) is used to receive the electrical signal corresponding to the excitation light and generate a differential signal; The controller (321) is used to sample the differential signal and convert the differential signal into communication data.

8. An underwater optical communication method based on a perovskite heterojunction detector, characterized in that: include: The excitation light emitting device modulates the communication data into excitation light consisting of light of at least one central wavelength according to a preset communication protocol, and emits the excitation light; The underwater optical communication component based on the perovskite heterojunction detector according to claim 1 receives the excitation light and outputs an electrical signal corresponding to the excitation light; The control acquisition system acquires the electrical signal corresponding to the excitation light and converts the electrical signal into the communication data.

9. The underwater optical communication method based on perovskite heterojunction detector according to claim 8, characterized in that: The control and acquisition system includes: a controller and a differential identification unit; The differential recognition unit receives the electrical signal corresponding to the excitation light and generates a differential signal; The controller samples the differential signal and converts the differential signal into communication data.

Images