Photonic quantum storage system and photonic quantum crystal storage method based on lithium niobate crystal

Abstract

The present invention discloses a photon storage system and a photon storage method based on lithium niobate crystals. The photon storage system includes: a lithium niobate single crystal film; a laser domain writing component, which is used to output a laser pulse of a first parameter group to the surface of the lithium niobate single crystal film, and to perform photon domain writing and data storage on the lithium niobate single crystal film; a laser detection component, wherein the detection end of the laser detection component corresponds to the reflective optical path setting of the lithium niobate single crystal film, and the laser detection component is used to detect the optical signal on the lithium niobate single crystal film and output the corresponding data signal. The present invention aims to solve the problems of low storage density and inability to transmit over long distances in traditional storage technology.

Description

Technical Field

[0001] The present invention relates to the field of photon information storage, and in particular to a photon storage system and a photon crystal storage method based on lithium niobate crystals. Background Art

[0002] Existing data storage technologies have some disadvantages. First, the read and write speed of hard disk drives (HDDs) is slow, and they rely on the operation of mechanical parts, which are prone to failure due to wear or impact. In addition, the operation of mechanical parts consumes a lot of electricity, especially in large-scale data centers. Although solid-state drives (SSDs) have advantages in speed, they cost more per GB (Gigabyte), and the write life of NAND flash memory is limited. After multiple writes, the performance will degrade, resulting in data loss and inability to transmit over long distances. The storage capacity of a single optical disc of optical storage (such as CDs and Blu-rays) is relatively small, which is not suitable for storing large amounts of data. The write speed is slow, and the disc is easily damaged by scratches, dust and heat, affecting the long-term preservation of data. Summary of the invention

[0003] The main purpose of the present invention is to propose a photon quantum storage system and a photon quantum crystal storage method based on lithium niobate crystals, aiming to solve the problems of low storage density and inability to transmit over long distances in traditional storage technologies.

[0004] To achieve the above object, the optical quantum storage system proposed by the present invention includes:

[0005] Lithium niobate single crystal thin film;

[0006] A laser domain writing component, used for outputting laser pulses of a first parameter group to the surface of the lithium niobate single crystal film, and performing photon domain writing and data storage on the lithium niobate single crystal film;

[0007] A laser detection component, wherein the detection end of the laser detection component is arranged corresponding to the reflection light path of the lithium niobate single crystal film, and the laser detection component is used to detect the optical signal on the lithium niobate single crystal film and output the corresponding data signal.

[0008] Optionally, the laser domain writing component comprises:

[0009] A first laser, used for outputting laser pulses;

[0010] A collimating lens, used to ensure the parallelism of the beam of the laser pulse;

[0011] A first polarizer, used for selecting the laser pulse at a preset angle;

[0012] A first half glass slide, used for adjusting the polarization state of the laser pulse;

[0013] The first focusing lens is used to increase the energy density of the laser pulse; the center points of the collimating lens, the first polarizer, the first half glass plate and the first focusing lens are arranged on the same horizontal line as the output end of the first laser, and the laser pulse emitted by the first laser passes through the collimating lens, the first polarizer, the first half glass plate and the first focusing lens in sequence and then focuses on the lithium niobate single crystal film.

[0014] Optionally, the laser detection assembly comprises:

[0015] A second polarizer, used for selecting the laser pulse at a preset angle;

[0016] The second half of the glass slide is used to adjust the polarization state of the laser pulse;

[0017] A second focusing lens, used to increase the energy density of the laser pulse;

[0018] a first chopper, arranged corresponding to the second polarizer, for modulating the intensity of the laser pulse;

[0019] A single-photon detector, wherein the center point of the second polarizer, the second half-glass, and the second focusing lens and the detection end of the single-photon detector are arranged on the same horizontal straight line corresponding to the lithium niobate single crystal film, the detection end of the single-photon detector is arranged corresponding to the reflection light path of the lithium niobate single crystal film, and the single-photon detector is used to detect the optical signal on the lithium niobate single crystal film and output the corresponding electrical signal;

[0020] A data processor is connected to the single-photon detector and is used to communicate with the terminal device. The data processor is used to process the electrical signal output by the single-photon detector and then output a corresponding data signal to the terminal device.

[0021] Optionally, the optical quantum storage system further includes:

[0022] The laser coupling component is used to output coupled laser and couple with the laser pulse output by the laser domain writing component to generate ultrafast laser pulses to the surface of the lithium niobate single crystal film, and perform optical quantum domain writing and data storage on the lithium niobate single crystal film.

[0023] Optionally, the laser coupling component comprises:

[0024] A second laser, used for outputting coupled laser light;

[0025] An electro-optic modulator, arranged corresponding to the second laser, for modulating the phase, amplitude or polarization of the coupled laser;

[0026] an acousto-optic modulator, arranged corresponding to the electro-optic modulator, for modulating the intensity, frequency or wavelength of the coupled laser;

[0027] The second chopper is arranged corresponding to the acousto-optic modulator and is used for modulating the intensity of the coupled laser.

[0028] The present invention also proposes a photon quantum crystal storage method based on lithium niobate crystal, which is applied to the photon quantum storage system as described above, comprising the following steps:

[0029] preparing a lithium niobate single crystal thin film, and performing high temperature annealing on the lithium niobate single crystal thin film;

[0030] Controlling the laser domain writing component to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film;

[0031] The laser detection component is controlled to detect the optical signal on the light path reflected by the lithium niobate single crystal film, and outputs the data signal after processing.

[0032] Optionally, the step of controlling the laser domain writing component to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film specifically includes:

[0033] The pulse power of the control laser pulse ranges from 1 mW to 10 mW, the data rate of the control laser pulse ranges from 10 kbps to 1 Mbps, and the pulse interval of the control laser pulse ranges from 10 ns to 100 ns.

[0034] Optionally, the step of controlling the laser domain writing component to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film specifically includes:

[0035] By adjusting one or more of the frequency, energy, and pulse width of the laser pulse in the first parameter group, one of periodic nanoscale domains, micron-scale domains, or mixed-scale domains is formed on the lithium niobate single crystal film.

[0036] Optionally, the step of forming one of periodic nanoscale domains, micron-scale domains or mixed-scale domains on the lithium niobate single crystal film by adjusting one or more of the frequency, energy and pulse width of the laser pulse in the first parameter group specifically includes:

[0037] The frequency range of the laser pulse is adjusted to be 100 kHz to 1 MHz, the energy range is 0.1 μJ to 1 μJ, and the pulse width range is 10 fs to 100 fs to form a periodic nanoscale domain structure on the lithium niobate single crystal film;

[0038] The frequency range of the laser pulse is adjusted to be 10 kHz to 100 kHz, the energy range is 1 μJ to 10 μJ, and the pulse width range is 100 fs to 1 ps to form a micrometer-scale domain structure on the lithium niobate single crystal film;

[0039] The frequency range of the laser pulse is adjusted to 50 kHz to 500 kHz, the energy range is 0.5 μJ to 5 μJ, and the pulse width range is 50 fs to 500 fs to form a mixed-scale domain structure on the lithium niobate single crystal film.

[0040] Optionally, the step of controlling the laser detection component to detect the optical signal on the light path reflected by the lithium niobate single crystal film and outputting the data signal after processing specifically includes:

[0041] The optical signal on the lithium niobate single crystal film is detected by a single photon detector, and the corresponding electrical signal is output to a data processor;

[0042] The control data processor processes the electrical signal and then outputs the data signal to the terminal device.

[0043] The technical solution of the present invention forms a photon storage system through a lithium niobate single crystal film, a laser domain writing component and a laser detection component, wherein the laser domain writing component can output a laser pulse of a first parameter group to the surface of the lithium niobate single crystal film, and perform photon domain writing and data storage on the lithium niobate single crystal film; the laser detection component is used to detect the optical signal on the lithium niobate single crystal film and output the corresponding data signal. Since the present solution adopts a lithium niobate single crystal film, the storage density can be improved by inducing the phase change of photons in the lithium niobate domain area at the atomic scale by ultrafast laser; and the photon domain writing is performed on the lithium niobate single crystal film. Since the single photon detection capability of the lithium niobate single crystal film domain engineering is strong, the loss of photons in the information transmission process can be reduced, and the long-distance transmission capability is improved; therefore, the present solution can solve the problems of low storage density and inability to transmit over long distances of traditional magnetic storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention 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 invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0045] Figure 1 This is a schematic diagram of the functional modules of an embodiment of the optical quantum storage system of the present invention;

[0046] Figure 2A schematic diagram of functional modules of another embodiment of the optical quantum storage system of the present invention;

[0047] Figure 3 This is a schematic diagram of functional modules of another embodiment of the optical quantum storage system of the present invention;

[0048] Figure 4 This is a flowchart of the method steps of an embodiment of the optical quantum crystal storage method based on lithium niobate crystal of the present invention;

[0049] Figure 5 This is a flowchart of the method steps of another embodiment of the optical quantum crystal storage method based on lithium niobate crystal of the present invention;

[0050] Figure 6 This is a flow chart of the method steps of another embodiment of the optical quantum crystal storage method based on lithium niobate crystals of the present invention.

[0051] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0053] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0054] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0055] Existing data storage technologies have some shortcomings and challenges. First, disk drives have slow read and write speeds and rely on the operation of mechanical parts. They are prone to failure due to wear or impact, and the operation of mechanical parts consumes a lot of electricity, especially in large-scale data centers. Although solid-state drives have advantages in speed, their cost per GB is high. NAND flash memory has a limited write life. After multiple writes, performance will degrade, resulting in data loss. In the event of a failure, data recovery is more difficult and has a lower success rate than disk drives. The storage capacity of a single optical disk of optical storage (such as CDs and Blu-ray) is relatively small, which is not suitable for storing large amounts of data. The write speed is slow, and the optical disk is susceptible to scratches, dust and heat damage, which affects the long-term preservation of data. Tape storage is mainly used for archiving and backup. The data access speed is slow and cannot meet the real-time access needs. The management and maintenance of tape libraries require specialized equipment and technicians, which increases the complexity. In addition, tapes are sensitive to environmental conditions such as temperature and humidity, and the storage and maintenance costs are high. Although cloud storage provides convenience, data is stored in third-party cloud service providers, which poses the risk of data leakage and privacy issues. At the same time, data access depends on the network, and network failures or bandwidth limitations may affect the speed of data access. As the amount of data increases, storage and access costs may rise. As an emerging technology, non-volatile storage is not yet fully mature, and there are problems with unstable performance or limited lifespan. In addition, the research and development and production costs of new technologies are high, and the application costs are also high. These shortcomings and challenges have driven the continuous innovation and development of data storage technology to better meet the needs of modern data storage and processing.

[0056] With the advancement of quantum information technology, humans can accurately detect and control the quantum state of microscopic systems. In response to the needs of large-capacity, high-speed transmission and confidential communication of information networks, relying on the characteristics of quantum communication with ultra-large channel capacity, ultra-high communication rate and high information efficiency, quantum key distribution technology is used to establish a superluminal quantum communication network that meets special needs. Among them, quantum memory is the core device for building large-scale quantum communication networks. Aiming at the application in the field of quantum communication, a new type of quantum memory with high density and low power consumption is developed. For the superluminal quantum communication network with special needs, a high-security, high-stability macro-photon quantum crystal domain storage system based on lithium niobate single crystal film is proposed. This new photon quantum crystal domain storage system can be applied to the fields of quantum computing and quantum communication to realize long-distance quantum secure information transmission. At the same time, the storage system can also be applied to storage devices such as smart phones and personal computers, realizing the application of high-density, low-power and secure storage technology in civilian and other aspects.

[0057] To this end, the present invention proposes an optical quantum storage system.

[0058] Reference Figures 1 to 3In one embodiment, the optical quantum storage system includes:

[0059] Lithium niobate single crystal thin film 1;

[0060] A laser domain writing component 100 is used to output a laser pulse of a first parameter group to the surface of the lithium niobate single crystal film 1 to perform photon domain writing and data storage on the lithium niobate single crystal film 1;

[0061] The laser detection component 200 has a detection end arranged corresponding to the reflection light path of the lithium niobate single crystal film 1 , and is used to detect the optical signal on the lithium niobate single crystal film 1 and output a corresponding data signal.

[0062] In this embodiment, a lithium niobate single crystal film 1 can be prepared on the basis of a lithium niobate single crystal; the lithium niobate single crystal film 1 has a higher surface flatness and a lower defect density than the lithium niobate single crystal material, which can improve the accuracy and stability of data storage; and the lithium niobate single crystal film 1 is easier to process and integrate in batches, which can improve production efficiency. For thin film materials, using multi-pulse or modulated pulse mode to output laser pulses can also further optimize writing efficiency and accuracy. Furthermore, compared with bulk lithium niobate materials, the lithium niobate single crystal film 1 has the following advantages in single photon storage: Since the lithium niobate single crystal film 1 has a smaller thickness, it can more effectively limit the propagation of the light field in the film, thereby increasing the intensity of the light field, which can enhance nonlinear effects such as the Kerr effect and Raman scattering, thereby improving the efficiency of single photon storage. Due to its high-quality crystal structure, the lithium niobate single crystal film 1 can reduce light propagation losses and realize optical resonators with high quality factors (Q factors), which allows photons to be stored in the resonator for a long time and reduces the loss of photons during information transmission. The thickness and doping of the lithium niobate single crystal film 1 can be precisely controlled to adjust the nonlinear optical and electro-optical properties of the material. By optimizing the manufacturing process of the lithium niobate single crystal film 1, the photon storage process can be finely controlled to achieve higher storage efficiency and storage time.

[0063] The lithium niobate single crystal film 1 can also be deposited on various substrate materials, such as silicon, sapphire, etc., which makes it compatible with different photonic integration platforms. The flexibility of the film also allows it to be applied to different device structures and geometries, providing more design freedom. And due to the uniformity and high quality of the single crystal film, the multi-path interference phenomenon generated by photons during propagation can be reduced, thereby improving the fidelity of photon storage. In this embodiment, a lithium niobate single crystal film 1 with a thickness of 500 nanometers can be prepared, and a lithium niobate single crystal film 1 with other thicknesses can also be prepared according to actual needs, without limitation here.

[0064] The laser domain writing component 100 can output laser pulses according to the first parameter group to irradiate the lithium niobate single crystal film 1, thereby performing photon domain writing on the lithium niobate single crystal film 1 and storing data. Specifically, an ultrafast laser can be used to generate femtosecond laser pulses, which are the core of photon storage, and the laser pulses emitted by the laser can be adjusted in wavelength through a frequency doubling crystal to adapt to different quantum storage requirements. It can be understood that the introduction of a periodic domain structure in the lithium niobate crystal can effectively regulate the optical and electrical properties of the lithium niobate material, thereby achieving efficient detection of single photons. The lithium niobate domain engineering can bring the following benefits to the single photon detector 20: by optimizing the domain structure of the lithium niobate single crystal film 1, the interaction between light and material can be enhanced, thereby improving the photon absorption efficiency. The domain structure of the lithium niobate single crystal film 1 can also effectively suppress the generation of thermal loads, thereby reducing the dark count rate. And the domain structure of the lithium niobate single crystal film 1 can enable the single photon detector 20 to operate in a wider temperature range. The domain structure of the lithium niobate single crystal film 1 can also realize a variety of functions, such as polarization sensitivity, wavelength selection, etc. Therefore, this scheme can improve the storage density by preparing the lithium niobate single crystal film 1; and perform photon quantum domain writing on the lithium niobate single crystal film 1 to enhance the single photon detection capability, which can reduce the loss of photons during information transmission, thereby enhancing the long-distance transmission capability. It should be noted that the laser pulse stores data on the lithium niobate single crystal film 1 through photoinduced polarization reversal, that is, the irradiation of the laser pulse can induce local polarization reversal. This is because the high-intensity laser beam can excite the nonlinear optical effect in the material, change the local electric field distribution, and thus cause the reversal of the polarization state. This polarization reversal can be used to represent the "1" or "0" state of the data, and the laser photons can cause the temperature change of the material through the photoelectric effect or the photothermal effect, thereby affecting the polarization direction. For example, ultraviolet or visible light lasers can excite the nonlinear effect of lithium niobate, causing the material to undergo local polarization reversal in the laser irradiation area. In this way, data writing and storage can be completed.

[0065] The laser domain writing component 100 of this embodiment may include a laser, and the laser is controlled to output laser pulses according to a first parameter group. The first parameter group may include pulse duration, repetition frequency, central wavelength, spot diameter, energy density, number of pulses, scanning speed, incident angle, pulse power, data rate, pulse interval, frequency, energy and pulse width of the laser pulse. By controlling the parameters of these laser pulses and the relative humidity and temperature of the surrounding environment, the lithium niobate single crystal film 1 can be photon domain written, and data can be stored on the lithium niobate single crystal film 1; wherein, a shorter pulse duration, such as a pulse duration in the range of 30fs to 100fs, can induce a strong nonlinear effect in the lithium niobate single crystal film 1 material, which is conducive to the formation of an efficient domain structure on the lithium niobate single crystal film 1; and a wavelength in the range of 800nm ​​to 1550nm, such as a titanium sapphire laser at 800nm ​​and a fiber laser at 1550nm, has moderate spectral characteristics and material absorption rate; sufficient peak power, such as 10kW to 100kW, and an average power of 100m The energy density can affect the size and shape of the domain, and needs to be adjusted appropriately to control the fineness of the domain structure, such as 0.1J / cm² to 1J / cm²; controlling the number of pulses can adjust the depth and durability of the domain, and multiple pulses can help enhance the stability of the domain, and the specific range can be 1 to 1000; the scanning speed will affect the writing time and the shape of the domain, and a slower speed, such as 1mm / s to 10mm / s, is usually used for the formation of fine structures; adjusting the incident angle can optimize the effect of the laser pulse on the crystal surface and reduce reflection loss, such as an incident angle of 0° to 15°; temperature control can improve the quality of the domain structure and avoid the adverse effects of thermal effects of materials at high temperatures, and the temperature range can be 20°C to 100°C; and keeping the relative humidity of the environment within an appropriate range can prevent the thin film material from getting damp and causing domain performance degradation, and the humidity range can be 30% to 50%. The specific parameter range provided in this embodiment is for reference only. The technicians can also make settings and adjustments according to the thickness of the lithium niobate single crystal film 1 and actual needs in practical applications, and there is no limitation here.

[0066] The laser detection component 200 can detect the lithium niobate single crystal film 1 by a single-photon detector, detect the light signal on the reflected light path of the lithium niobate single crystal film 1, and can also detect the light signal on the transmitted light path of the lithium niobate single crystal film 1, and output the corresponding electrical signal, thereby completing the reading of the data stored on the lithium niobate single crystal film 1.

[0067] The technical solution of the present invention forms a photon storage system through a lithium niobate single crystal film 1, a laser domain writing component 100 and a laser detection component 200, wherein the laser domain writing component 100 can output a laser pulse of a first parameter group to the surface of the lithium niobate single crystal film 1, and perform photon domain writing and data storage on the lithium niobate single crystal film 1; the laser detection component 200 is used to detect the optical signal on the lithium niobate single crystal film 1 and output the corresponding data signal. Since the present solution adopts a lithium niobate single crystal film 1, the storage density can be improved by inducing the phase change of photons in the lithium niobate domain region at the atomic scale by ultrafast laser; and the photon domain writing is performed on the lithium niobate single crystal film 1. Since the single photon detection capability of the domain engineering of the lithium niobate single crystal film 1 is strong, the loss of photons in the process of information transmission can be reduced, and the long-distance transmission capability can be improved; therefore, the present solution can solve the problems of low storage density and inability to transmit over long distances of traditional magnetic storage.

[0068] Reference Figure 3 In one embodiment, the laser domain writing assembly 100 comprises:

[0069] A first laser 2, used for outputting laser pulses;

[0070] A collimating lens 3, used to ensure the parallelism of the beam of the laser pulse;

[0071] A first polarizer 4, used for selecting the laser pulse at a preset angle;

[0072] The first half glass slide 5 is used to adjust the polarization state of the laser pulse;

[0073] The first focusing lens 6 is used to increase the energy density of the laser pulse; the center points of the collimating lens 3, the first polarizer 4, the first half glass 5 and the first focusing lens 6 are arranged on the same horizontal line as the output end of the first laser 2, and the laser pulse emitted by the first laser 2 passes through the collimating lens 3, the first polarizer 4, the first half glass 5 and the first focusing lens 6 in sequence and then focuses on the lithium niobate single crystal film 1.

[0074] In this embodiment, the first laser 2 is a device that can emit adjustable laser pulses, and outputs corresponding laser pulses according to the first parameter group through the collimating lens 3, the first polarizer 4, the first half glass 5 and the first focusing lens 6. The collimating lens 3 can ensure the parallelism of the laser pulse beam, the first polarizer 4 can select the laser pulse of the preset angle, the first half glass 5 can adjust the polarization state of the laser pulse, and the first focusing lens 6 can focus the laser pulse to increase the energy density of the laser pulse so that it can be irradiated on the lithium niobate single crystal film 1 for photon quantum domain writing and data storage. In practical applications, the optical elements in the laser domain writing component 100 can also include an objective lens 7, a deformable mirror 8, a filter 9 and a phase plate 10, etc.; wherein the deformable mirror 8 is an optical element that can dynamically adjust the shape of its optical surface to perform wavefront correction on the laser pulse and change the beam quality; the filter 9 can realize functions such as spectrum selection and color correction; and the phase plate 10 can adjust the phase of the laser pulse without changing the intensity of the light. It is understandable that by setting the center points of the optical elements on the same horizontal straight line, the collimation of the laser pulse, the quality of the laser pulse beam and the convergence of the laser pulse energy can be ensured, and the laser pulse can enter the optical fiber to reduce the loss in spatial light propagation and increase the stability of transmission. It is understandable that the laser pulse after polarization adjustment can also enter the optical fiber for optical fiber coupling, thereby reducing the loss in spatial light propagation and increasing the stability of transmission. The specific number and position relationship of the optical elements in this embodiment can be set and adjusted according to actual needs.

[0075] Reference Figure 3 In one embodiment, the laser detection assembly 200 includes:

[0076] A second polarizer 41, used for selecting the laser pulse at a preset angle;

[0077] The second half glass slide 51 is used to adjust the polarization state of the laser pulse;

[0078] A second focusing lens 61, used to increase the energy density of the laser pulse;

[0079] A first chopper 11, arranged corresponding to the second polarizer 41, for modulating the intensity of the laser pulse;

[0080] The single-photon detector 20, the center point of the second polarizer 41, the second half glass 51 and the second focusing lens 61 and the detection end of the single-photon detector 20 are arranged on the same horizontal straight line corresponding to the lithium niobate single crystal film 1, and the detection end of the single-photon detector 20 is arranged corresponding to the reflection light path of the lithium niobate single crystal film 1. The single-photon detector 20 is used to detect the optical signal on the lithium niobate single crystal film 1 and output the corresponding electrical signal;

[0081] A data processor is connected to the single-photon detector 20 and is used to communicate with the terminal device. The data processor is used to process the electrical signal output by the single-photon detector 20 and output a corresponding data signal to the terminal device.

[0082] In this embodiment, the optical elements in the laser detection assembly 200 may be provided with a corresponding second polarizer 41, a second half glass 51, a second focusing lens 61 and a first chopper 11. The single-photon detector 20 may be a device such as an avalanche photodiode, a superconducting nanowire single-photon detector, a photomultiplier tube, a single-photon multiplier tube or a quantum dot single-photon source. By using the single-photon detector 20, the light signal reflected or transmitted from the lithium niobate single crystal film 1 can be detected, and the stored information can be extracted by adjusting the phase and amplitude of the reflection. Among them, the reflection phase range is: 0° to 360°. The phase modulation amplitude can reach up to 180°; the phase resolution range is: 0.01° to 1°. The phase change is between 0° and 360°, which can be achieved by electro-optical modulation. The amplitude range is: 0.1 to 1.0. The amplitude change range is: 20% to 80%, which can be achieved by adjusting the reflection / transmission ratio. The amplitude resolution range is: 0.001 to 0.01, and the amplitude range depends on the reflection or transmission characteristics of the optical signal on the film. By adjusting the amplitude, the intensity encoding and decoding process of the information can be controlled. The single-photon detector 20 detects the photons on the lithium niobate single crystal film 1, that is, the optical signal, and then amplifies the signal and outputs the corresponding electrical signal to the data processor; the signal processing system decodes the electrical signal to obtain the stored information and outputs the data signal to the terminal device. Among them, the data processor and the terminal device are not shown in the figure. The data processor can be a digital signal processor (Digital Signal Processor, referred to as DSP), a programmable logic device (Programmable Logic Device, referred to as PLD), a field programmable gate array (Field Programmable Gate Array, referred to as FPGA), a microprocessor, an MCU single chip or other electronic components. The data processor can process the electrical signal output by the single-photon detector 20 and output the corresponding data signal to the terminal device. The terminal device can be a computer or other equipment. In this way, the storage information on the lithium niobate single crystal film 1 in the optical quantum storage system can be obtained through the terminal device. It can be understood that setting the center points of the optical elements on the same horizontal line can ensure the collimation of the laser pulse, the quality of the laser pulse beam and the convergence of the laser pulse energy, and can allow the laser pulse to enter the optical fiber to reduce the loss in spatial light propagation and increase the stability of transmission.

[0083] Reference Figure 2 In one embodiment, the optical quantum storage system further includes:

[0084] The laser coupling component 300 is used to output coupled laser and couple with the laser pulse output by the laser domain writing component 100 to generate ultrafast laser pulses to the surface of the lithium niobate single crystal film 1 to perform photon domain writing and data storage on the lithium niobate single crystal film 1.

[0085] In this embodiment, by coupling the laser pulse output by the laser coupling component 300 with the laser pulse output by the laser writing domain component 100, an ultrafast laser pulse can be generated on the surface of the lithium niobate single crystal film 1; the ultrafast laser pulse induces the photon to produce a phase change in the lithium niobate domain at the atomic scale, thereby further realizing an improvement in storage density. Under the action of the photon, macro information writing at a lower mesoscopic scale can be achieved.

[0086] Further, refer to Figure 3 In one embodiment, the laser coupling assembly 300 includes:

[0087] A second laser 21, used for outputting coupled laser light;

[0088] An electro-optic modulator 12, arranged corresponding to the second laser, for modulating the phase, amplitude or polarization of the coupled laser;

[0089] an acousto-optic modulator 13, arranged corresponding to the electro-optic modulator 12, for modulating the intensity, frequency or wavelength of the coupled laser;

[0090] The second chopper 111 is arranged corresponding to the acousto-optic modulator 13 and is used to modulate the intensity of the coupled laser.

[0091] In this embodiment, the second laser 21 is a device that can emit adjustable laser pulses, the electro-optic modulator 12 can change the propagation characteristics of light, such as phase, amplitude or polarization; the acousto-optic modulator 13 can modulate the intensity, frequency or wavelength of light; and after the coupled laser output by the second laser 21 is modulated by the electro-optic modulator 12 and the acousto-optic modulator 13, it can be coupled with the laser pulse emitted by the first laser 2 to generate ultrafast laser.

[0092] Furthermore, in one embodiment, the optical quantum storage system of the present scheme may also include a phase-locked amplifier and a feedback control system (not shown in the figure). By controlling the phase-locked amplifier and the feedback control system, the phase, frequency and intensity of the laser pulse can be kept within a preset range. In this embodiment, the phase range of the laser pulse can be: 0° to 360°, then the phase stability range is: ±0.01° to ±0.1°, and the phase adjustment accuracy range is: 0.001° to 0.01°; such that the phase change is controlled between 0° and 360°, it can ensure high-precision phase stability during signal encoding and decoding. The frequency range of the laser pulse is: 80MHz to 200MHz, then the frequency stability range is: ±1Hz to ±10Hz, and the frequency resolution range is: 0.01Hz to 1Hz. Therefore, frequency stability is the basis for maintaining stable operation of the laser. In practical applications, accurate frequency locking is usually achieved through phase-locked loop technology. The intensity range of laser pulses is: 1mW to 100mW (average power), 10kW to 100kW (peak power); the intensity stability range is: ±0.1% to ±1%, and the intensity adjustment accuracy range is: 0.01mW to 0.1mW (average power adjustment accuracy). Through the optical feedback control system and adjustable attenuator, the intensity can be precisely adjusted.

[0093] The present invention also proposes a photon quantum crystal storage method based on lithium niobate crystal, which is applied to the photon quantum storage system as described above.

[0094] Reference Figure 4 In one embodiment, the optical quantum crystal storage method based on lithium niobate crystal includes the following steps:

[0095] S100, preparing a lithium niobate single crystal film 1, and performing high temperature annealing on the lithium niobate single crystal film 1;

[0096] S200, controlling the laser domain writing component 100 to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film 1;

[0097] S300, controlling the laser detection component 200 to detect the optical signal on the light path reflected by the lithium niobate single crystal film 1, and outputting a data signal after processing.

[0098] In this embodiment, lithium niobate can be deposited onto a preset substrate by chemical vapor deposition or molecular beam epitaxy technology to form a lithium niobate single crystal film 1. The thickness of the lithium niobate single crystal film 1 can be controlled in the nanometer range, thereby improving its optical performance. Furthermore, in order to improve the crystal quality of the lithium niobate single crystal film 1, high temperature annealing can also be performed to reduce the defect density and improve the optical quality. Among them, the preset substrate can be one of a silicon substrate, a sapphire substrate, a germanium substrate, a quartz substrate, an aluminum oxide substrate, a magnesium substrate or a gallium arsenide substrate. Because of the optical and electro-optical properties of the lithium niobate single crystal film 1, it is compatible with a variety of substrates. This compatibility enables the lithium niobate single crystal film 1 to perform well in a variety of application scenarios.

[0099] For example, silicon substrates can be used in photonic integrated circuits; the combination of silicon substrates and lithium niobate single crystal film 1 can improve the integration and compatibility of optoelectronic devices. Its advantage lies in high integration. The co-integration of electronic and photonic devices can be achieved using the existing complementary metal oxide semiconductor (CMOS) process, which can reduce production costs. Efficient optical modulation, the high electro-optic coefficient of lithium niobate single crystal film 1 enables high-speed optical modulation in silicon-based circuits. Due to the small size and high performance of lithium niobate single crystal film 1, miniaturized, low-loss optical modulators and switches can be manufactured. For example, silicon-based optical modulators are used in data centers and high-speed communications to achieve efficient data transmission; or silicon-based optical switches are used in optical networks and routing to provide flexible optical path switching.

[0100] Sapphire substrates can be used in high-temperature photoelectric sensors. Sapphire substrates are suitable for applications in extreme environments due to their excellent thermal stability and optical transparency. The combination of lithium niobate single crystal film 1 and sapphire can manufacture photoelectric sensors that work stably at high temperatures. Its advantages are: High temperature stability: Ability to maintain the stability of physical and optical properties under high temperature conditions. Wide spectral response: Suitable for optical applications in a wide spectral range, especially infrared light sensing in high temperature environments. Corrosion resistance: Provides chemical stability and is suitable for harsh environments. For example, infrared light detectors are used for gas detection in the oil and gas fields under high temperature environments. Or high-temperature pressure sensors are suitable for the aerospace field to monitor pressure changes in aircraft and rocket engines.

[0101] Germanium substrate, can be used in infrared optical devices. The application of lithium niobate single crystal film 1 on germanium substrate is mainly concentrated in infrared optical devices. The infrared transparency of germanium makes it an ideal substrate material for manufacturing infrared detectors and sensors. Its advantages are: Infrared transparency: provides excellent infrared light penetration, suitable for infrared band applications. Enhanced photoelectric conversion efficiency: combined with lithium niobate, it can improve the efficiency of infrared detectors. High thermal conductivity: improves the heat dissipation performance of the device under high-power applications. For example, infrared detectors are used for infrared imaging. Or infrared sensors are used in industry for thermal imaging and gas leak detection.

[0102] Quartz substrate can be used in optical sensing and communication. The combination of quartz substrate and lithium niobate single crystal film 1 is suitable for optical sensing and optical communication. The low loss characteristics of quartz make it an ideal choice for long-wavelength communication. Its advantages are: Low optical loss: It provides extremely low light transmission loss and is suitable for long-distance optical communication. High-precision optical device manufacturing: It is suitable for manufacturing high-precision filters and wave plates. For example, optical fiber communication systems, modulators and demodulators for data transmission. Or precision optical filters for spectral analysis and dispersion compensation.

[0103] Alumina substrate can be used in high-frequency electronic devices. The application of aluminum substrate combined with lithium niobate single crystal film 1 is mainly concentrated in high-frequency electronic devices. Due to the excellent electrical insulation of aluminum oxide, it is suitable for use in high-frequency and high-voltage environments. Its advantages are: High dielectric constant: provides excellent electric field control capabilities. Excellent thermal conductivity: improves heat dissipation efficiency in high-power applications. High mechanical strength: provides excellent mechanical stability and is suitable for harsh environments. For example, microwave devices, filters and oscillators for wireless communications. Or high-frequency power amplifiers, to achieve efficient power amplification in 5G communications.

[0104] Magnesium substrates can be used in portable optical devices. The lightweight properties of magnesium substrates make them ideal for portable optical devices, and the combination with lithium niobate single crystal thin film 1 makes them perform well in mobile devices. Its advantages are: Lightweight: suitable for applications that require portability and mobility. High strength: provides good structural strength, suitable for miniaturized optical devices. Environmental resistance: maintains stable performance under a variety of environmental conditions. For example, portable lasers are used in portable ranging and detection equipment. Or handheld spectrometers for on-site analysis in field environments.

[0105] Gallium arsenide substrate can be applied to optoelectronic integrated devices. Gallium arsenide substrate combined with lithium niobate single crystal thin film 1 is mainly used in optoelectronic integrated devices, especially in high-speed optical communication and optoelectronic conversion. Its advantages are: High electron mobility: provides excellent electrical performance and improves optoelectronic conversion efficiency. Efficient optoelectronic conversion: performs well in high-speed data transmission. Wide bandgap material: suitable for high-power and high-frequency applications. For example, laser diodes are used in high-speed optical fiber communication and data transmission. Or photodetectors, to achieve efficient optoelectronic conversion and signal processing.

[0106] The multi-substrate compatibility of the lithium niobate single crystal film 1 enables it to be applied in various application fields to meet the needs of different application scenarios.

[0107] The laser domain writing component 100 can output laser pulses according to the first parameter group to irradiate the lithium niobate single crystal film 1, thereby performing photon domain writing on the lithium niobate single crystal film 1 and storing data. Specifically, an ultrafast laser can be used to generate femtosecond laser pulses, which are the core of photon storage, and the laser pulses emitted by the laser can be adjusted in wavelength through a frequency doubling crystal to adapt to different quantum storage requirements. It can be understood that the introduction of a periodic domain structure in the lithium niobate crystal can effectively regulate the optical and electrical properties of the lithium niobate material, thereby achieving efficient detection of single photons. The laser detection component 200 may include a single photon detector 20, and the lithium niobate domain engineering may bring the following benefits to the single photon detector 20: by optimizing the domain structure of the lithium niobate single crystal film 1, the interaction between light and material can be enhanced, thereby improving the photon absorption efficiency. The domain structure of the lithium niobate single crystal film 1 can also effectively suppress the generation of thermal loads, thereby reducing the dark count rate. And the domain structure of the lithium niobate single crystal film 1 can enable the single photon detector 20 to operate in a wider temperature range. The domain structure of the lithium niobate single crystal film 1 can also realize a variety of functions, such as polarization sensitivity, wavelength selection, etc. Therefore, this solution can improve the storage density by preparing the lithium niobate single crystal film 1; and perform photon quantum domain writing on the lithium niobate single crystal film 1 to improve the single photon detection capability, which can reduce the loss of photons during information transmission, thereby enhancing the long-distance transmission capability. In addition, the lithium niobate single crystal film 1 can be detected by the single photon detector 20, the optical signal on the lithium niobate single crystal film 1 can be detected, and the corresponding electrical signal can be output, thereby completing the reading of the data stored on the lithium niobate single crystal film 1.

[0108] In one embodiment, the step of controlling the laser domain writing component 100 to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film 1 specifically includes:

[0109] The pulse power of the control laser pulse ranges from 1 mW to 10 mW, the data rate of the control laser pulse ranges from 10 kbps to 1 Mbps, and the pulse interval of the control laser pulse ranges from 10 ns to 100 ns.

[0110] In this embodiment, when writing data to the lithium niobate single crystal film 1, the laser parameters can be used to encode information into the formed domain structure, so the pulse power, data rate and pulse interval within the preset range of the laser output can be controlled to complete the data writing to the lithium niobate single crystal film 1. For example, the pulse power range can be 1mW to 10mW. Using a relatively low power for data writing can avoid damage to the existing domain structure. For the modulation method of the laser pulse, amplitude modulation (AM), phase modulation (PM) or frequency modulation (FM) can be used to modulate the laser to encode the data signal. The data rate can range from 10kbps to 1Mbps. The data rate determines the speed and efficiency of information writing, and the appropriate rate needs to be selected according to the application requirements. The pulse interval can range from 10ns to 100ns, and the pulse interval time will affect the accuracy of data writing and the stability of the domain structure. The above parameter ranges in this embodiment are only for reference, and can also be adjusted according to actual conditions. This embodiment is not limited here.

[0111] Reference Figure 5 In one embodiment, the step of controlling the laser domain writing component 100 to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film 1 specifically includes:

[0112] S210, forming one of periodic nanoscale domains, micron-scale domains or mixed-scale domains on the lithium niobate single crystal film 1 by adjusting one or more of the frequency, energy and pulse width of the laser pulse in the first parameter group.

[0113] In this embodiment, photon domain writing is to write photon domains on the lithium niobate single crystal film 1 by ultrafast laser emitted by a laser. This step can create a specific domain structure on the film by precisely adjusting laser parameters such as frequency, energy and pulse width. The domain structure is formed in the film by the photoelectric effect for subsequent quantum information storage. Therefore, photon domain writing is a key step in writing storage information to the lithium niobate single crystal film 1. Its purpose is to generate a domain structure for data writing on the film. The periodic nanoscale domains, micron-scale domains and mixed-scale domains in this embodiment can be respectively applied to different scenarios. The periodic nanoscale domain structure can be applied to photonic crystals and metasurface optical devices, such as wavelength selection and optical waveguides in photonic crystal optical fibers; in metasurface optical devices such as optical microscopes, it can be applied to lenses and filters. The micron-scale domain structure can be applied to nonlinear optical devices and modulators, such as optical frequency doubling conversion in frequency multipliers; and signal modulation in optical communications in electro-optical modulators. The hybrid scale domain structure can be applied to integrated optical devices and quantum memories. In integrated optical devices, it can be used for multi-wavelength multiplexing and demultiplexing; in quantum memories, it can achieve efficient quantum information storage and retrieval. Therefore, which domain structure is formed on the lithium niobate single crystal film 1 can be selected according to the actual application scenario.

[0114] Further, refer to Figure 6 In one embodiment, the step of forming one of periodic nanoscale domains, micron-scale domains or mixed-scale domains on the lithium niobate single crystal film by adjusting one or more of the frequency, energy and pulse width of the laser pulse in the first parameter group specifically includes:

[0115] S211, adjusting the frequency range of the laser pulse to 100 kHz to 1 MHz, the energy range to 0.1 μJ to 1 μJ, and the pulse width range to 10 fs to 100 fs, so as to form a periodic nanoscale domain structure on the lithium niobate single crystal film 1;

[0116] S212, adjusting the frequency range of the laser pulse to 10 kHz to 100 kHz, the energy range to 1 μJ to 10 μJ, and the pulse width range to 100 fs to 1 ps, so as to form a micron-scale domain structure on the lithium niobate single crystal film 1;

[0117] S213, adjusting the frequency range of the laser pulse to 50kHz to 500kHz, the energy range to 0.5μJ to 5μJ, and the pulse width range to 50fs to 500fs to form a mixed scale domain structure on the lithium niobate single crystal film 1.

[0118] In this embodiment, for the periodic nanoscale domain structure, the laser frequency range is a high frequency of 100kHz to 1MHz, which helps to produce a uniform microstructure in the lithium niobate single crystal film 1. The laser energy range is 0.1μJ to 1μJ, that is, a low-energy laser pulse, which helps to refine the formation of the nanostructure and avoid material damage. The pulse width ranges from 10fs to 100fs, that is, an ultra-short pulse width, which helps to localize material processing and provide fine structural resolution. The domain size formed in this way ranges from 20nm to 100nm, that is, a nanoscale domain structure. The domain spacing ranges from 100nm to 300nm, and the scanning speed and frequency of the laser can be specifically controlled to adjust the domain spacing to achieve periodic arrangement. The surface morphology control of the periodic nanoscale domain structure can be achieved by controlling the scanning path of the laser through a precision positioning system or by using a lens to adjust the focus to achieve high-precision control. The specific writing method is to use focused ultrafast laser pulses to form a periodic nanoscale domain structure on a single crystal film using nonlinear optical effects. This method can achieve high-density storage and is suitable for application scenarios that require fast reading and writing. The impact on the single photon detector 20 is mainly reflected in the improvement of detection efficiency and response speed. The specific performance parameters are: detection efficiency: >90%; dark count rate: <10Hz; time resolution: <100ps; operating temperature range: -20°C to 60°C; response wavelength range: 400nm-800nm.

[0119] For micron-scale domain structures, the laser frequency ranges from 10kHz to 100kHz, that is, medium frequency, which can be used to form larger micron-scale domains. The laser energy ranges from 1μJ to 10μJ, that is, medium energy, which is suitable for micron-scale structure processing and ensures the integrity of domain formation. The pulse width ranges from 100fs to 1ps, that is, a slightly longer pulse width, which increases the range of influence on the material and is conducive to the formation of large-size domains. The domain size range formed in this way is 1μm to 10μm. And the formed micron-scale domains are conducive to enhancing nonlinear optical effects. And the domain spacing ranges from 10μm to 50μm, such a large domain spacing is suitable for phase matching of nonlinear optical processes to optimize nonlinear effects. The specific writing method is to use modulated laser pulses to form a larger micron-scale domain structure on the film. It can be used in situations where long-term storage and high stability are required. Its impact on the single-photon detector 20 is mainly to reduce the dark count rate and improve the stability of storage. The specific performance parameters are: detection efficiency: about 85%; dark count rate: <1Hz; time resolution: about 200ps; operating temperature range: -40°C to 85°C; response wavelength range: 450nm-950nm.

[0120] For the mixed-scale domain structure, the laser frequency ranges from 50kHz to 500kHz, that is, the mixed frequency, which can be used to generate multi-scale structures, taking into account both nanoscale and micron-scale structures. The laser energy ranges from 0.5μJ to 5μJ, that is, medium energy, which can achieve the coexistence of multiple structures and is suitable for complex optical functions. The pulse width ranges from 50fs to 500fs. This pulse width is a relatively flexible pulse width relative to the pulse width for forming periodic nanoscale domain structures and micron-scale domain structures, and can allow domains of different scales to be formed simultaneously. The range of domain size formed in this way is 50nm to 5μm, that is, a mixed-scale domain structure, which can be used for composite optical functions. And the range of domain spacing is 200nm to 20μm, which can support multifunctional integrated devices. The specific writing method combines the advantages of nanoscale and micron-scale domain structures, and realizes the generation of mixed domain structures by adjusting the laser pulse parameters. In this way, the combined advantages of the two domain structures are provided, which is suitable for multifunctional storage needs. The impact on the single-photon detector 20 is to take into account both high detection efficiency and low dark count rate. The specific performance parameters are: detection efficiency: about 88%; dark count rate: <5Hz; time resolution: about 150ps; operating temperature range: -30°C to 70°C; response wavelength range: 420nm-900nm.

[0121] The specific parameters of the three domain structures can be found in the table below:

[0122]

[0123] In one embodiment, the step of controlling the laser detection assembly 200 to detect the optical signal on the light path reflected by the lithium niobate single crystal film 1 and outputting the data signal after processing specifically includes:

[0124] The optical signal on the lithium niobate single crystal film 1 is detected by the single photon detector 20, and the corresponding electrical signal is output to the data processor;

[0125] The control data processor processes the electrical signal and then outputs the data signal to the terminal device.

[0126] In this embodiment, the optical signal reflected or transmitted from the lithium niobate single crystal film 1 can be detected by using a single-photon detector 20, and the stored information can be extracted by adjusting the phase and amplitude of the reflection. Among them, the reflection phase range is: 0° to 360°. The phase modulation amplitude can reach up to 180° at most; the phase resolution range is: 0.01° to 1°. The phase change between 0° and 360° can be achieved by electro-optical modulation. The amplitude range is: 0.1 to 1.0. The amplitude change range is: 20% to 80%, which can be achieved by adjusting the reflection or transmission ratio. The amplitude resolution range is: 0.001 to 0.01, and the amplitude range depends on the reflection or transmission characteristics of the optical signal on the lithium niobate single crystal film 1. By adjusting the amplitude, the intensity encoding and decoding process of the information can be controlled. The single-photon detector 20 detects the photons on the lithium niobate single crystal film 1, that is, the optical signal, then amplifies the signal and outputs the corresponding electrical signal to the data processor; the data processor decodes the electrical signal to obtain the stored information and outputs the data signal to the terminal device, which can be a computer or other device.

[0127] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. An optical quantum storage system, characterized in that: include: Lithium niobate single crystal thin film; A laser domain writing component is used to output a laser pulse of a first parameter group to the surface of the lithium niobate single crystal film, to perform photon domain writing and data storage on the lithium niobate single crystal film, wherein the first parameter group includes pulse duration, repetition frequency, central wavelength, spot diameter, energy density, number of pulses, scanning speed, incident angle, pulse power, data rate, pulse interval, frequency, energy and pulse width of the laser pulse, and to complete photon domain writing on the lithium niobate single crystal film and perform data storage on the lithium niobate single crystal film by controlling the parameters of the laser pulse and the relative humidity and temperature of the surrounding environment; A laser detection component, wherein the detection end of the laser detection component is arranged corresponding to the reflection light path of the lithium niobate single crystal film, and the laser detection component is used to detect the optical signal on the lithium niobate single crystal film and output a corresponding data signal; The laser detection component includes a single-photon detector, and the detection end of the single-photon detector is arranged on the same horizontal line corresponding to the lithium niobate single crystal film. The detection end of the single-photon detector is arranged corresponding to the reflection light path of the lithium niobate single crystal film. The single-photon detector is used to detect the optical signal on the lithium niobate single crystal film and output the corresponding electrical signal.

2. The optical quantum storage system according to claim 1, characterized in that: The laser domain writing assembly comprises: A first laser, used for outputting laser pulses; A collimating lens, used to ensure the parallelism of the beam of the laser pulse; A first polarizer, used for selecting the laser pulse at a preset angle; A first half glass slide, used for adjusting the polarization state of the laser pulse; The first focusing lens is used to increase the energy density of the laser pulse; the center points of the collimating lens, the first polarizer, the first half glass plate and the first focusing lens are arranged on the same horizontal line as the output end of the first laser, and the laser pulse emitted by the first laser passes through the collimating lens, the first polarizer, the first half glass plate and the first focusing lens in sequence and then focuses on the lithium niobate single crystal film.

3. The optical quantum storage system according to claim 1, characterized in that: The laser detection assembly comprises: A second polarizer, used for selecting the laser pulse at a preset angle; The second half of the glass slide is used to adjust the polarization state of the laser pulse; A second focusing lens, used to increase the energy density of the laser pulse; a first chopper, arranged corresponding to the second polarizer, for modulating the intensity of the laser pulse; The center points of the second polarizer, the second half glass plate and the second focusing lens are arranged on the same horizontal line corresponding to the lithium niobate single crystal film; A data processor is connected to the single-photon detector and is used to communicate with the terminal device. The data processor is used to process the electrical signal output by the single-photon detector and then output a corresponding data signal to the terminal device.

4. The optical quantum storage system according to claim 1, characterized in that: The optical quantum storage system also includes: The laser coupling component is used to output coupled laser and couple with the laser pulse output by the laser domain writing component to generate ultrafast laser pulses to the surface of the lithium niobate single crystal film, and perform optical quantum domain writing and data storage on the lithium niobate single crystal film.

5. The optical quantum storage system according to claim 4, characterized in that: The laser coupling assembly comprises: A second laser, used for outputting coupled laser light; An electro-optic modulator, arranged corresponding to the second laser, for modulating the phase, amplitude or polarization of the coupled laser; an acousto-optic modulator, arranged corresponding to the electro-optic modulator, for modulating the intensity, frequency or wavelength of the coupled laser; The second chopper is arranged corresponding to the acousto-optic modulator and is used for modulating the intensity of the coupled laser.

6. A method for storing photon quantum crystals based on lithium niobate crystals, applied to the photon quantum storage system according to any one of claims 1 to 5, characterized in that: The following steps are involved: preparing a lithium niobate single crystal thin film, and performing high temperature annealing on the lithium niobate single crystal thin film; Controlling the laser domain writing component to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film; The laser detection component is controlled to detect the optical signal on the light path reflected by the lithium niobate single crystal film, and outputs the data signal after processing.

7. The optical quantum crystal storage method based on lithium niobate crystal according to claim 6, characterized in that: The step of controlling the laser domain writing component to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film specifically includes: The pulse power of the control laser pulse ranges from 1 mW to 10 mW, the data rate of the control laser pulse ranges from 10 kbps to 1 Mbps, and the pulse interval of the control laser pulse ranges from 10 ns to 100 ns.

8. The optical quantum crystal storage method based on lithium niobate crystal as claimed in claim 6, characterized in that: The step of controlling the laser domain writing component to output laser pulses according to the first parameter group to perform photon domain writing and data storage on the lithium niobate single crystal film specifically includes: By adjusting one or more of the frequency, energy, and pulse width of the laser pulse in the first parameter group, one of periodic nanoscale domains, micron-scale domains, or mixed-scale domains is formed on the lithium niobate single crystal film.

9. The optical quantum crystal storage method based on lithium niobate crystal as claimed in claim 8, characterized in that: The step of forming one of periodic nanoscale domains, micron-scale domains or mixed-scale domains on the lithium niobate single crystal film by adjusting one or more of the frequency, energy and pulse width of the laser pulse in the first parameter group specifically includes: The frequency range of the laser pulse is adjusted to be 100 kHz to 1 MHz, the energy range is 0.1 μJ to 1 μJ, and the pulse width range is 10 fs to 100 fs to form a periodic nanoscale domain structure on the lithium niobate single crystal film; The frequency range of the laser pulse is adjusted to be 10 kHz to 100 kHz, the energy range is 1 μJ to 10 μJ, and the pulse width range is 100 fs to 1 ps to form a micrometer-scale domain structure on the lithium niobate single crystal film; The frequency range of the laser pulse is adjusted to 50 kHz to 500 kHz, the energy range is 0.5 μJ to 5 μJ, and the pulse width range is 50 fs to 500 fs to form a mixed-scale domain structure on the lithium niobate single crystal film.

10. The optical quantum crystal storage method based on lithium niobate crystal according to claim 6, characterized in that: The step of controlling the laser detection component to detect the optical signal on the light path reflected by the lithium niobate single crystal film and outputting the data signal after processing specifically includes: The optical signal on the lithium niobate single crystal film is detected by a single photon detector, and the corresponding electrical signal is output to a data processor; The control data processor processes the electrical signal and then outputs the data signal to the terminal device.

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