All-optical single-photon detection feedback operation multiplexed single-photon source

Abstract

An all-optical single-photon detection feedback operation multiplexed single-photon source belongs to the fields of quantum information and quantum optics. The present invention includes a pulsed laser pump source, an entangled photon pair light source array, an all-optical readout single-photon detector, an optical signal collector, a spatial multiplexing optical path, a temporal multiplexing optical path, and a single-photon output optical path. The entangled photon pair light source array is used for probabilistically generating an array of idler light and an array of signal light that are entangled under the excitation of the pulsed laser pump source by multiple entangled photon pair light sources; the all-optical readout single-photon detector is used for detecting and feeding back the idler light array signal; the optical signal collector is used for collecting and discriminating the optical signals output by the single-photon detector to generate corresponding multi-channel modulation voltage signals; the spatial multiplexing optical path is used for coupling multiple signal lights to the same optical path; the temporal multiplexing optical path is used for synthesizing the optical signals with multiple timestamps into one timestamp through a delay operation; the single-photon output optical path is used for measuring or outputting the final single-photon signal.

Description

Technical Field

[0001] The present invention belongs to the technical field of quantum information and quantum optics, and particularly relates to an expandable all-optical single-photon detection feedback operation multiplexed single-photon source, which is applicable to optical quantum precision measurement applications. Background Art

[0002] A deterministic single-photon source is a light source that deterministically emits and only emits one photon at periodic time intervals, and can be used to prepare large-scale optical quantum entangled states, achieve large-scale boson sampling, etc., and plays a crucial role in fields such as optical quantum computing, long-distance quantum communication, and optical quantum precision measurement.

[0003] Based on single atoms or atom-like systems, such as single molecules, diamond color centers, semiconductor quantum dots, etc., single photons can be generated through spontaneous emission by exciting an equivalent two-level system from the ground state to the excited state. Self-assembled semiconductor quantum dots currently achieve the single-photon source with the highest comprehensive performance in this type of system. However, such systems usually require complex sample preparation and low-vibration cryogenic optical systems, and need to be integrated into a highly matched microcavity coupling to improve the collection efficiency of single photons. The single-photon preparation efficiency is also limited by quantum efficiency, collection coupling efficiency, etc.

[0004] Multiplexing based on multiple probabilistically generated correlated photon pair sources is a technical approach to asymptotically realize a deterministic single-photon source. Common methods for generating correlated photon pair sources include spontaneous parametric down-conversion processes and spontaneous four-wave mixing processes. For each pump of the laser, there is a certain probability that a correlated photon pair source generates a pair of photons. By detecting one of the modes, it is possible to predict whether there is a photon in the other mode, and thus a single photon can be prepared predictively. Kaneda et al. in the United States multiplexed 40 spontaneous parametric down-conversion sources through the time degree of freedom and achieved an efficiency enhancement of approximately 9.7 times. The efficiency of the multiplexed single-photon source reached 66.7%. However, due to the use of high pump power, the purity of the multiplexed single-photon source they obtained, represented by the second-order correlation function is only . Therefore, in the future, in order to achieve a multiplexed single-photon source with more excellent comprehensive performance, that is, to simultaneously meet high efficiency and high purity, it is necessary to improve the efficiency of the multiplexed single-photon source as much as possible while also ensuring that the generation efficiency of a single correlated photon pair source is small enough. The most reasonable approach is to increase the number of multiplexed light sources N . A key technical challenge for future multiplexed single-photon sources lies in simultaneously achieving high efficiency and high-speed single-photon detection feedback for multiple channels.

[0005] At present, superconducting nanowire single-photon detectors have the best performance in terms of detection efficiency, dark count rate, time jitter and other parameters, and can work in the near-infrared band. This detector can distinguish between the absence of photons and at least one photon. In recent years, it has become an indispensable tool in quantum optics. The operation of superconducting single-photon detectors needs to be carried out in a low-temperature environment. In large-scale multiplexing of single-photon sources and optical quantum information experiments, the number of multiplexed light sources N may reach 100 or even more than 1,000, so it is necessary to operate single-photon detectors of multiple channels at the same time. For example, in the experiment of verifying the superiority of optical quantum computing, more than 100 superconducting single-photon detectors need to be operated simultaneously. However, the cooling performance of traditional cryogenic equipment limits the number of superconducting nanowire single-photon detection chips that can be read independently in a single system, and the radio frequency transmission line of the transmission detection signal of the multi-channel superconducting nanowire single-photon detector will introduce a huge heat load. Thermal radiation will introduce the dark count of the single-photon detector to form an erroneous trigger prediction signal; in addition, the transmission speed of electrical signals is slow, and the signal photon needs to be delayed for a longer time to wait for the feedback operation signal, which will introduce additional photon loss. The efficiency of single-photon source is one of the most important indicators in the fields of optical quantum computing, quantum precision measurement, etc. Designing a method for preparing a high-speed detection feedback operation multiplexed single-photon source is an important issue that needs to be urgently solved in the current field of optical quantum technology. Summary of the invention

[0006] In order to solve the problems of low efficiency and poor scalability of single-photon sources, the purpose of the present invention is to provide an all-optical single-photon detection feedback operation multiplexing single-photon source, use an all-optical readout single-photon detector for predictive detection, and adopt a combination of space and time multiplexing to achieve parallel detection and multiplexing operation of multi-channel probabilistically correlated photon sources, solve the problems of low efficiency and slow detection feedback speed of probabilistic light sources, and have scalability.

[0007] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0008] The all-optical single-photon detection feedback operation multiplexed single-photon source disclosed by the present invention includes a pulsed laser pump source, an entangled photon pair light source array, an all-optical readout single-photon detector, an optical signal collector, a spatial multiplexing optical path, a temporal multiplexing optical path, and a single-photon output optical path. The laser emitted by the pulsed laser pump source excites the entangled photon pair light source array to generate an entangled idler light array and a signal light array. After the light arrays are coupled, they are respectively transmitted to the all-optical readout single-photon detector and the spatial multiplexing optical path via single-mode optical fibers. The all-optical readout single-photon detector detects the single-photon signals of the idler light array and feeds back classical optical signals. The optical signal collector collects and discriminates the classical optical signals and converts them into electrical signals, which are synchronously transmitted to the spatial multiplexing optical path and the temporal multiplexing optical path to control the optical switches in the optical paths. When the idler light detector of the entangled photon pair light source responds, the corresponding optical switch in the spatial multiplexing optical path performs polarization flipping or retention, so that the single photons in the corresponding spatial path mode can pass through the spatial multiplexing optical path to reach the output path and be transmitted to the temporal multiplexing optical path. The optical switch in the temporal multiplexing optical path controls through polarization flipping or retention to merge the single photons in different time modes into the same time mode after passing through different delay optical paths.

[0009] The pulsed laser pump source is used to generate pulsed lasers with high repetition rates.

[0010] The entangled photon pair light source array is used for multiple entangled photon pair light sources to probabilistically generate an entangled idler light array and a signal light array under the excitation of the pulsed laser pump source. After corresponding optical coupling, each path is collected into a single-mode optical fiber.

[0011] The all-optical readout single-photon detector is used to detect and feedback the idler light array signals.

[0012] The optical signal collector is used to collect and discriminate the optical signals output by the single-photon detector and generate corresponding multi-channel modulation voltage signals.

[0013] The spatial multiplexing optical path is used to couple multiple signal lights into the same optical path.

[0014] The temporal multiplexing optical path is used to synthesize the optical signals with multiple timestamps into one timestamp through delay operations.

[0015] The single-photon output optical path is used to measure or output the final single-photon signals, including a polarization beam splitting measurer and a collection coupler.

[0016] Furthermore, the all-optical readout single-photon detector includes a superconducting nanowire detection chip array, a cryogenic photodiode, a cryogenic amplifier array, and a cryogenic optical modulation array.

[0017] The superconducting nanowire detection chip array is used to receive the signals accessed to the superconducting working temperature region through the single-mode optical fiber and the coupler by the entangled photon pair light source array and perform detection.

[0018] The low-temperature photodiode is used to receive the pulsed laser signal introduced by the pulsed laser pump source through a single-mode optical fiber and generate a bias current.

[0019] The low-temperature amplifier array operates in a low-temperature disk in a temperature region different from the superconducting temperature region, and is used to amplify the photocurrent signal output by the superconducting nanowire detector chip array.

[0020] The voltage signals generated by the low-temperature photodiode and the superconducting nanowire detector chip array are amplified by the low-temperature amplifier array and then transmitted to the low-temperature optical modulation array. The voltage generates an electric field in the waveguide, and the refractive index of the waveguide interferometer is changed through the electro-optic effect, thereby changing the port of the waveguide interferometer that outputs the optical signal and outputting a feedback optical signal.

[0021] Furthermore, the signal light emitted from the correlated photon pair source in the spatial multiplexing optical path sequentially passes through a polarization beam splitter, an optical lens, an electro-optic modulator, and a mirror, and finally is combined into the same spatial mode by a beam combiner.

[0022] Furthermore, the time multiplexing optical path includes an unequal-arm interferometer and an electro-optic modulator. The unequal-arm interferometer includes a delay optical loop, an electro-optic modulator, a mirror, and a beam displacement combiner. The electro-optic modulator makes photons deterministically pass through optical paths with different delays by controlling the polarization of photons, so that optical signals in different time modes are combined into the same time mode.

[0023] Furthermore, the pulsed laser pump source is used to generate pump laser pulses and input optical signals for the low-temperature diode.

[0024] Furthermore, the correlated photon pair source array includes a correlated photon pair source, a signal light array, and an idler light array. The correlated photon pair source is used to probabilistically generate photon pairs with a high heralding efficiency.

[0025] Furthermore, the optical signal collector has the functions of collection and feedback, and is used to collect and discriminate the optical signals output by the single-photon detector and generate corresponding multi-channel modulation voltage signals.

[0026] Furthermore, the single-photon output optical path includes an electro-optic modulator, a polarization beam splitter for measurement, and a collection coupler, which can ensure that the output photons are of a single polarization and are collected into a single-mode optical fiber. Beneficial effects

[0027] 1. The all-optical single-photon detection feedback operation multiplexed single-photon source disclosed by the present invention uses a superconducting nanowire single-photon detector to detect the idler optical signal. Compared with the avalanche photodiode single-photon detector used previously, it has the characteristics of high efficiency and low dark count, and the available working band can be extended to the optical communication band and the mid-infrared band, which is suitable for generating multiplexed single-photon sources in the communication band.

[0028] 2. The all-optical single-photon detection feedback operation multiplexed single-photon source disclosed by the present invention uses an optical reading method for superconducting nanowire single-photon detectors. Since there is no need to connect radio frequency signal transmission lines between low temperature and room temperature, it can significantly reduce the thermal load of the single-photon detector, increase the number of superconducting nanowire detection chips that can be expanded by a single refrigerator, and solve the problems of the cost and complexity of the refrigerator.

[0029] 3. The all-optical single-photon detection feedback operation multiplexed single-photon source disclosed by the present invention uses optical signal transmission, which is faster than radio frequency signal transmission, and has a speed advantage in the preparation of multiplexed single-photon sources that require high-speed and high-efficiency active feedback manipulation.

[0030] 4. The all-optical single-photon detection feedback operation multiplexed single-photon source disclosed by the present invention uses a combined scheme of spatial multiplexing and time multiplexing, which can increase the number of multiplexed correlated photon pair light sources, realize parallel detection and multiplexing operation of multi-channel probabilistic correlated photon sources, and significantly improve the preparation efficiency of multiplexed single-photon sources.

[0031] 5. On the basis of achieving the above beneficial effects, the all-optical single-photon detection feedback operation multiplexed single-photon source disclosed by the present invention can use an all-optical read superconducting nanowire detector to perform predictive detection and feedback signal output on multiple correlated photon pairs, and realize the preparation of multiplexed single-photon sources, and can be applied to fields such as optical quantum computing and quantum precision measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is the schematic diagram of the all-optical single-photon detection feedback operation multiplexed single-photon source according to the embodiment of the present disclosure;

[0033] Figure 2 is the schematic diagram of the all-optical single-photon detection feedback operation multiplexed single-photon source solution according to the embodiment of the present disclosure;

[0034] Figure 3 is the schematic diagram of the phase modulation waveguide interferometer according to the embodiment of the present disclosure;

[0035] Among them, 1 - pulsed laser pump source, 2 - correlated photon pair light source array, 2a - first correlated photon pair light source, 2b - second correlated photon pair light source, 2c - third correlated photon pair light source, 2d - fourth correlated photon pair light source, 2e - fifth correlated photon pair light source, 2f - sixth correlated photon pair light source, 2g - seventh correlated photon pair light source, 2h - eighth correlated photon pair light source, 3 - all-optical readout single-photon detector, 310 - superconducting nanowire detection chip array, 320 - cryogenic photodiode, 330 - cryogenic amplifier array, 340 - cryogenic optical modulation array, 341 - first waveguide, 342 - second waveguide, 343 - waveguide mirror, 344 - electrode, 4 - idler light array, 4a - first single-mode fiber coupler, 4b - second single-mode fiber coupler, 4c - third single-mode fiber coupler, 4d - fourth single-mode fiber coupler, 4e fifth single-mode fiber coupler, 4f - sixth single-mode fiber coupler, 4g - seventh single-mode fiber coupler, 4h - eighth single-mode fiber coupler, 5 - signal light array, 6 - spatial multiplexing optical path, 6a - first polarization beam splitter, 6b - second polarization beam splitter, 6c - third polarization beam splitter, 6d - fourth polarization beam splitter, 7 - time multiplexing optical path, 8 - optical signal collector, 9a - first optical lens, 9b - second optical lens, 9c - third optical lens, 9d - fourth optical lens, 10 - first optical modulator, 11 - second optical modulator, 12 - third optical modulator, 13 - fourth optical modulator, 14 - fifth optical modulator, 15 - sixth optical modulator, 16a - first mirror, 16b - second mirror, 16c - third mirror, 16d - fourth mirror, 16e - fifth mirror, 16f - sixth mirror, 17 - first beam combiner, 18 - second beam combiner, 19 - third beam combiner, 20 - seventh optical modulator, 21 - first unequal-arm interferometer, 21a - fourth beam combiner, 21b - fifth beam combiner, 21c - first delay optical loop, 22 - second unequal-arm interferometer, 22a - sixth beam combiner, 22b - seventh beam combiner, 22c - second delay optical loop, 23 - eighth optical modulator, 24 - ninth optical modulator, 25 - fifth polarization beam splitter, 26 - first single-mode fiber output coupler, 27 - second single-mode fiber output coupler. Detailed implementation manner

[0036] The main object of the present invention is to solve the problems of low efficiency of single-photon sources and slow detection feedback speed and poor scalability of multiplexed single-photon sources. To make the object, technical solution and advantages of the present invention more clear and understandable, the following combines specific embodiments and refers to the accompanying drawings to further elaborate on the present invention in detail.

[0037] In the embodiment, as Figure 2As shown, the all-optical single-photon detection feedback operation multiplexed single-photon source disclosed in this embodiment is used to realize the prediction detection and feedback signal output of multiple correlated photon pairs by using all-optical reading of a superconducting nanowire detector, and to realize the preparation of a multiplexed single-photon source, which is applied to fields such as optical quantum computing and quantum precision measurement. The working process of the preparation scheme of the all-optical single-photon detection feedback operation multiplexed single-photon source is as follows:

[0038] In this embodiment, the pulsed laser pump source 1 generates periodic laser pulses, and the laser is transmitted to the correlated photon pair light source array 2, and pumps in parallel or in series N=8 spontaneous parametric down-conversion correlated photon pair light sources, which are respectively denoted as the first correlated photon pair light source 2a, the second correlated photon pair light source 2b, the third correlated photon pair light source 2c, the fourth correlated photon pair light source 2d, the fifth correlated photon pair light source 2e, the sixth correlated photon pair light source 2f, the seventh correlated photon pair light source 2g, and the eighth correlated photon pair light source 2h. Optionally, the correlated photon pair light source can adopt a spontaneous four-wave mixing parametric light source, a quantum dot biexciton emission two-photon light source, etc. The quantum state of a single correlated photon pair light source can be approximately represented at a low order in the particle number representation as , where represents the probability of generating 0 pairs of photons, represents the probability of generating 1 pair of photons, represents the probability of generating 2 pairs of photons. Usually, in order to ensure better single-photon purity, by adjusting the pump light power, .

[0039] The idler light arrays 4 of the correlated photon pair light source array 2 are respectively collected into single-mode optical fibers through the first single-mode fiber coupler 4a, the second single-mode fiber coupler 4b, the third single-mode fiber coupler 4c, the fourth single-mode fiber coupler 4d, the fifth single-mode fiber coupler 4e, the sixth single-mode fiber coupler 4f, the seventh single-mode fiber coupler 4g, and the eighth single-mode fiber coupler 4h, and are introduced into the all-optical readout single-photon detector 3 through multiple single-mode optical fibers. Optionally, the first single-mode fiber coupler 4a can be connected to an optical fiber splitter for further splitting operation for quasi-photon number resolution detection.

[0040] For the convenience of clear representation, only the optical path schematic diagram of the case of N = 8 is shown in the drawings. It should be noted that it can be further extended to a larger number.

[0041] In this embodiment, the superconducting nanowire detection chip array 310 in the all-optical readout single-photon detector 3 includes multiple superconducting nanowire detection chips, which can efficiently convert the incident single-photon signal into an electrical signal. The superconducting nanowire detection chip has the characteristics of an efficiency greater than 90% and a dark count <50 Hz.

[0042] In this embodiment, after the cryogenic photodiode 320 receives the laser emitted by the pulsed laser pump source 1, a bias current can be generated. The bias current and the electrical signal output by the superconducting nanowire detection chip are input into the cryogenic amplifier array 330 for electrical signal amplification. The amplified electrical signal is input into the cryogenic optical modulation array 340, which includes a phase modulation waveguide interferometer. As Figure 3 shown in the schematic diagram of the phase modulation waveguide interferometer, the phase modulation waveguide interferometer is composed of a first waveguide 341 and a second waveguide 342 that are coupled to each other. The coupling forms a 50:50 optical beam splitter, and waveguide mirrors 343 are coated on two of its end faces. The input end of the phase modulation waveguide interferometer is connected to a pulsed laser signal, and an electrode 344 is coated on one of the interference arms. When no electrical signal is loaded on the electrode 344, through initial phase processing, the optical signal input from the first waveguide 341 of the interferometer will return along the original path. When a voltage is loaded on the electrode 344, the refractive index of the waveguide is changed through the electro-optic effect, and a phase difference is introduced in the interference arm. The output light of the interferometer will be output from the second waveguide 342 and output to the room temperature environment through the coupled output fiber array from the all-optical readout single-photon detector 3. By using the optical modulation method, it has the characteristics of small signal rise time and recovery time, large detector self-resetting ability, and large detector saturation count rate.

[0043] In this embodiment, the optical signal collector 8 respectively and rapidly collects the optical signals output by the coupled output fiber array, generates a feedback square wave pulse according to the arrival time of the rising edge, and outputs it through the room temperature radio frequency transmission cable. The optical signal collector 8 can be used for threshold discrimination, that is, only optical signals reaching a specific intensity can be detected and the feedback square wave pulse can be output, thereby reducing the requirement for the high extinction ratio of the phase modulation waveguide interferometer and being more experimentally robust.

[0044] In this embodiment, the signal light in the associated photon pair light source array 2 includes 8 paths, forming a signal light array 5, which is transmitted to the spatial multiplexing optical path 6 through free space. Taking the signal light beams generated by the first associated photon pair light source 2a and the second associated photon pair light source 2b as an example, the technical solution of the spatial multiplexing optical path 6 is described as follows: The two light beams first undergo polarization-dependent beam combination through the first polarization beam splitter 6a, and then pass through the first optical lens 9a for beam focusing and beam waist position adjustment, so that the light beams have an appropriate beam waist size when incident on the first optical modulator 10, ensuring the optical transmittance and polarization extinction ratio. The first optical modulator 10 performs two operations of polarization flipping or polarization retention under the excitation of the feedback signal introduced by the optical signal collector 8, ensuring that the photons generated by the first associated photon pair light source 2a and the second associated photon pair light source 2b pass through the first beam combiner 17 after passing through the first mirror 16a and the second mirror 16b, and after the polarization operation of the fifth optical modulator 14, further pass through the third mirror 16c and the sixth mirror 16f and then pass through the third beam combiner 19. Similarly, other signal light beams pass through the second polarization beam splitter 6b, the third polarization beam splitter 6c, the fourth polarization beam splitter 6d, the second optical lens 9b, the third optical lens 9c, the fourth optical lens 9d, the second optical modulator 11, the third optical modulator 12, the fourth optical modulator 13, the sixth optical modulator 15, the fourth mirror 16d, the fifth mirror 16e, and the second beam combiner 18 and then converge into one spatial mode, and are input into the time multiplexing optical path 7 through the third beam combiner 19.

[0045] In this embodiment, Figure 1 A principle optical path for multiplexing 4 timestamps into 1 timestamp is shown. The optical signal output from the spatial multiplexing optical path 6 first undergoes polarization flipping or retention of the optical signal through the seventh optical modulator 20, and then is input into the first unbalanced interferometer 21. The first unbalanced interferometer 21 includes a fourth beam combiner 21a, a fifth beam combiner 21b, and a first optical delay loop 21c, and can perform an operation with an optical path of 1 pulse interval, that is, the optical signal passing through the first optical delay loop and the optical signal directly passing through the short arm of the first unbalanced interferometer 21 will have a delay of 1 pulse interval optical path. Through the operation of the seventh optical modulator 20, it is possible to switch whether the photon signal passes through the first optical delay loop 21c or directly through the short arm and then enter the second unbalanced interferometer 22 through the eighth optical modulator 23. The second unbalanced interferometer 22 includes a sixth beam combiner 22a, a seventh beam combiner 22b, and a second optical delay loop 22c, and the second optical delay loop 22c can generate an optical path of 2 pulse intervals. Therefore, through the action of the seventh optical modulator 20 and the eighth optical modulator 23, it is possible to synthesize adjacent 4 pulse signals into 1 time mode after delay.

[0046] In this embodiment, the photons after time-division multiplexing optical paths first undergo polarization flipping or polarization-invariant operations through the ninth optical modulator 24, and pass through the fifth polarization beam splitter 25 to ensure that the polarization of the finally output photons is single polarization. Finally, they are collected by the first single-mode fiber output coupler 26 and / or the second single-mode fiber output coupler 27 to output the multiplexed single photons.

[0047] For the disclosed embodiments, in the case where all components are ideal, through highly efficient single-photon detection and fast active feedback switches, in principle, by multiplexing entangled photon pair sources, the efficiency of the light source is increased to , which is much greater than the generation efficiency of a single entangled photon pair source , and as increases, the multiplexing efficiency can asymptotically reach 100%. In this embodiment, in order to reduce the thermal load of the detector, low-thermal-conductivity optical fibers are used for the interconnection from room temperature to low temperature. These interconnections can not only provide the working power supply for the superconducting nanowire single-photon detector, but also transmit the detection signal to the ambient temperature environment, which can significantly increase the number of detectors that can be placed by a single cryocooler. And the optical signal transmission is faster than the electrical signal transmission, which can improve the speed of the prediction detection feedback, reduce the length of the delayed transmission of the signal photons, and thus increase the prediction efficiency.

[0048] For the disclosed embodiments, the number of multiplexed light sources of the present invention has scalability. On the premise of ensuring the stability of the optical path construction, it can significantly increase the number of modes of the prediction detector, and can meet the requirements for the preparation of multiplexed single-photon sources with higher efficiency and higher purity, so as to meet the applications of high-precision quantum precision measurement. It should be noted that the embodiments and the drawings only show the specific implementations of the spatial multiplexing optical path of 8 light sources and the time-stamp multiplexing optical path of 4, and the number of multiplexed light sources is not limited to the embodiments.

[0049] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. All-optical single-photon detection feedback operation multiplexing single-photon source, characterized by: The invention comprises a pulse laser pump source, a correlated photon pair light source array, an all-optical readout single-photon detector, an optical signal collector, a spatial multiplexing optical path, a temporal multiplexing optical path and a single-photon output optical path; the correlated photon pair light source array comprises a correlated photon pair light source, a signal light array and an idler light array, and the correlated photon pair light source is used to probabilistically generate photon pairs with high prediction efficiency; after coupling, the optical array is respectively transmitted to the all-optical readout single-photon detector and the spatial multiplexing optical path via a single-mode optical fiber; the all-optical readout single-photon detector detects the single-photon signal of the idler light array and feeds back a classical optical signal, and the optical signal is collected. The collector collects and identifies the classical optical signal and converts it into an electrical signal, and transmits it synchronously to the spatial multiplexing optical path and the time multiplexing optical path to control the optical switch in the optical path; when the associated photon responds to the idler light detector of the light source, the corresponding optical switch in the spatial multiplexing optical path performs polarization flipping or holding, so that the single photon in the corresponding spatial path mode can reach the output path through the spatial multiplexing optical path and be transmitted to the time multiplexing optical path; the optical switch in the time multiplexing optical path controls the single photons in different time modes to merge into the same time mode after passing through different delay optical paths through polarization flipping or holding; Pulse laser pump source, used to generate high repetition rate pulse laser; A correlated photon pair light source array, which is used for a plurality of correlated photon pair light sources to probabilistically generate correlated idler light arrays and signal light arrays under the excitation of the pulsed laser pump source, and each path is collected into a single-mode optical fiber after corresponding optical coupling; All-optical readout single-photon detector for detecting and feeding back idler light array signals; An optical signal collector is used to collect and identify the optical signal output by the single-photon detector and generate a corresponding multi-channel modulated voltage signal; A spatial multiplexing optical path is used to couple multiple signal lights into the same optical path; A time multiplexing optical path is used to synthesize optical signals of multiple time stamps into one time stamp through a delay operation; A single-photon output optical path, used to measure or output the final single-photon signal, including a polarization beam splitter and a collection coupler; The all-optical readout single-photon detector comprises a superconducting nanowire detection chip array, a low-temperature photodiode, a low-temperature amplifier array and a low-temperature optical modulation array.

2. The all-optical single-photon detection feedback operation multiplexing single-photon source according to claim 1, characterized in that: The superconducting nanowire detection chip array is used to receive and detect the signal of the associated photon pair light source array connected to the superconducting working temperature zone through the single-mode optical fiber and the coupler; The low-temperature photodiode is used to receive the pulse laser signal introduced by the pulse laser pump source through the single-mode optical fiber to generate a bias current; The cryogenic amplifier array operates in a temperature zone different from the superconducting temperature zone and is used to amplify the photocurrent signal output by the superconducting nanowire detection chip array; The voltage signal generated by the low-temperature photodiode and superconducting nanowire detection chip array is amplified by the low-temperature amplifier array and then transmitted to the low-temperature optical modulation array. The voltage generates an electric field in the waveguide, which changes the refractive index of the waveguide interferometer through the electro-optical effect, thereby changing the port of the waveguide interferometer outputting the optical signal and outputting a feedback optical signal.

3. The all-optical single-photon detection feedback operation multiplexing single-photon source according to claim 1, characterized in that: The spatial multiplexing optical path means that the signal light emitted from the associated photon pair light source passes through the polarization beam splitter, optical lens, electro-optic modulator and reflector in sequence, and is finally combined into the same spatial mode by the beam combiner.

4. The all-optical single-photon detection feedback operation multiplexing single-photon source according to claim 1, characterized in that: The time multiplexing optical path includes an unequal-arm interferometer and an electro-optical modulator; the unequal-arm interferometer includes a time-delay optical ring and a beam displacement combiner; the electro-optical modulator controls the polarization of photons so that photons pass through optical paths with different delays in a deterministic manner, thereby merging optical signals of different time modes into the same time mode.

5. The all-optical single-photon detection feedback operation multiplexing single-photon source according to claim 1, characterized in that: The pulse laser pump source is used to generate pump laser pulses and low-temperature photodiode input light signals.

6. The all-optical single-photon detection feedback operation multiplexing single-photon source according to claim 1, characterized in that: The optical signal collector has collection and feedback functions, and is used to collect and identify the optical signal output by the single-photon detector, and generate corresponding multi-channel modulation voltage signals.

7. The all-optical single-photon detection feedback operation multiplexing single-photon source according to claim 1, characterized in that: The single-photon output optical path includes an electro-optic modulator, a polarization beam splitter and a collection coupler, which can ensure that the output photons are single polarized and collected into a single-mode optical fiber.

Images