A multi-output quantum random number generation device and a multi-output quantum random number generation method

Abstract

The present application discloses a multi-channel output quantum random number generation device and a multi-channel output quantum random number generation method. The multi-channel output quantum random number generation device includes a laser light source, a cascaded beam splitter module, a first homodyne detector, a second homodyne detector, a first signal processing module, a second signal processing module, and a control module. The technical solution of the present application obtains two optical signals with the same randomness at the entropy source level through optical path design, and obtains quantum noise by separately detecting these two optical signals and converts them into the same quantum random numbers. The whole process does not require the copying of electronic data, retains the true randomness of the two entropy sources, and reduces the risk of data being stolen and tampered with.

Description

Technical Field

[0001] This application belongs to the field of quantum information. Specifically, it relates to a quantum random number generation device and a quantum random number generation method. Background Art

[0002] In network communication, two sets of identical random numbers are sometimes required between multiple communication devices to implement some application scenarios. It is not appropriate to transmit these two sets of identical random numbers to two or more devices by copying the data network transmission method to ensure information security. For example, in a multi-factor authentication system, multiple devices may need to use the same random challenge or verification code to verify the user's identity; in a distributed system, multiple nodes may need to use the same random data to determine data distribution, replication, or fault recovery strategies; in an online game, the random data of the client must be the same as the random numbers on the server side to maintain the consistency of the game scenarios on the server side and the client side.

[0003] One existing technical solution is to call existing library functions on the server side to generate random numbers. For example, the srand function is used to set the random seed, and rand is used to generate random numbers; then the generated random numbers are transmitted to the client through the network. However, the random numbers generated and transmitted by this method are all pseudo-random numbers, and their security cannot cope with various network security vulnerabilities, resulting in poor security.

[0004] A quantum random number generator (QRNG) is a device that generates random numbers using quantum mechanical effects. The generation of the random numbers it produces not only has inherent randomness and security, but also has been widely used in many fields due to the improvement of the bandwidth of the entropy source itself, the detection bandwidth and efficiency of the processing circuit. However, currently, even when using a quantum random number generator to generate two sets of identical random numbers, it is necessary to copy the generated random numbers through the backend and then send them to another terminal for use. In this way, on the one hand, the copied random numbers do not have the true randomness of the original, and it also increases the risk of data being stolen and tampered with. Summary of the Invention

[0005] To solve the above technical problems, this application provides a multi-channel output quantum random number generation device and a multi-channel output quantum random number generation method. The specific solutions are as follows:

[0006] This application discloses a multi-channel output quantum random number generation device, including a laser light source, a cascaded beam splitter module, a first homodyne detector, a second homodyne detector, a first signal processing module, a second signal processing module, and a control module;

[0007] The cascaded beam splitter module includes a first beam splitter, a second beam splitter, and a third beam splitter. All three beam splitters include an upper input end, a lower input end, an upper output end, and a lower output end. The upper input end of the first beam splitter is connected to the laser light source, and the lower input end of the first beam splitter is left vacant; the lower input end of the second beam splitter is connected to the upper output end of the first beam splitter, and the upper input end of the third beam splitter is connected to the lower output end of the first beam splitter;

[0008] Two input ends of the first homodyne detector are respectively connected to the upper output end of the second beam splitter and the upper output end of the third beam splitter, and two input ends of the second homodyne detector are respectively connected to the lower output end of the second beam splitter and the lower output end of the third beam splitter;

[0009] The first signal processing module is connected to the output end of the first homodyne detector and is used to process and convert the signal output by the first homodyne detector into a first raw random number sequence. The second signal processing module is connected to the second homodyne detector and is used to process and convert the signal output by the second homodyne detector into a second raw random number sequence;

[0010] The control module is connected to the output ends of the first signal processing module and the second signal processing module and is used to perform post-processing, sampling inspection, extraction on the first raw random number sequence and the second raw random number sequence and output them respectively through two output ports. The control module is also connected to the first beam splitter, the second beam splitter, and the third beam splitter and is used to control the beam splitting ratio of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:50.

[0011] Further, the first homodyne detector includes a first photodetector, a third photodetector, a first current differentiator, and a first transimpedance amplifier. The input ends of the first photodetector and the third photodetector serve as the two input ends of the first homodyne detector. The output ends of the first photodetector and the third photodetector are both connected to the first current differentiator, the output end of the first current differentiator is connected to the first transimpedance amplifier, and the output end of the first transimpedance amplifier serves as the output end of the first homodyne detector; the second homodyne detector includes a second photodetector, a fourth photodetector, a second current differentiator, and a second transimpedance amplifier. The second photodetector is connected to the lower output end of the second beam splitter, the fourth photodetector is connected to the lower output end of the third beam splitter. The input ends of the second photodetector and the fourth photodetector serve as the two input ends of the second homodyne detector. The output ends of the third photodetector and the fourth photodetector are both connected to the second current differentiator, the output end of the second current differentiator is connected to the second transimpedance amplifier, and the output end of the second transimpedance amplifier serves as the output end of the second homodyne detector.

[0012] Further, the first beam splitter, the second beam splitter, and the third beam splitter are all MZ interferometers and respectively include a first phase modulator, a second phase modulator, and a third phase modulator. The first phase modulator, the second phase modulator, and the third phase modulator are all connected to a control module, and are used to control the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:50 according to the adjustment of the control module.

[0013] Further, the first beam splitter, the second beam splitter, and the third beam splitter are integrally fabricated on a substrate through a monolithic integration process.

[0014] Further, the upper input end of the second beam splitter and the lower input end of the third beam splitter both include a light-shielding layer, which is used to shield the ambient light interference and internal reflection of the upper input end of the second beam splitter and the lower input end of the third beam splitter.

[0015] Further, the cascaded beam splitter module is coupled to the first homodyne detector and the second homodyne detector through optical fibers, and the optical fiber lengths between the cascaded beam splitter module and the first homodyne detector and between the cascaded beam splitter module and the second homodyne detector are different.

[0016] Further, the control module includes a post-processing chip, a control chip, and a current source;

[0017] The post-processing chip is connected to the first signal processing module and the second signal processing module. The control module performs post-processing on the first original random number sequence and the second original random number sequence through the post-processing chip to obtain uniformly distributed random numbers. The current source is simultaneously connected to the first phase modulator, the second phase modulator, and the third phase modulator. The control chip is simultaneously connected to the post-processing chip, the current source, and the output ends of the first homodyne detector and the second homodyne detector. The control module performs sampling inspection, extraction, and output on the post-processed random numbers through the control chip, and controls the current source to regulate the first phase modulator, the second phase modulator, and the third phase modulator based on the current signals in the first homodyne detector and the second homodyne detector.

[0018] The present application also discloses a multi-channel output quantum random number generation method, which is applied to the above multi-channel output quantum random number generation device. The method includes:

[0019] The laser light source generates continuous laser light and inputs it into the cascaded beam splitter module through the upper input end of the first beam splitter;

[0020] The control module controls the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:50;

[0021] The first homodyne detector detects and processes the optical intensities output from the upper end of the output of the second beam splitter and the upper end of the output of the third beam splitter to convert them into a first voltage signal, and the second homodyne detector detects and processes the optical intensities output from the lower end of the output of the second beam splitter and the lower end of the output of the third beam splitter to convert them into a second voltage signal;

[0022] The first signal processing module filters and performs analog-to-digital conversion on the first voltage signal to obtain a first original random number sequence, and the second signal processing module filters and performs analog-to-digital conversion on the second voltage signal to obtain a second original random number sequence;

[0023] The control module performs post-processing, sampling inspection, and extraction on the first original random number sequence and the second original random number sequence to obtain two sets of identical random numbers, which are finally output through two output ports respectively.

[0024] Further, the first beam splitter, the second beam splitter, and the third beam splitter are all MZ interferometers and respectively include a first phase modulator, a second phase modulator, and a third phase modulator. The first phase modulator, the second phase modulator, and the third phase modulator are all connected to the control module; the control module includes a post-processing chip, a control chip, and a current source. The post-processing chip is connected to the first signal processing module and the second signal processing module. The current source is simultaneously connected to the first phase modulator, the second phase modulator, and the third phase modulator. The control chip is simultaneously connected to the post-processing chip, the current source, and the output ends of the first homodyne detector and the second homodyne detector;

[0025] The method further includes:

[0026] The control module performs sampling inspection, extraction, and output on the random numbers obtained through post-processing through the control chip, and the control chip also controls the current source to regulate the first phase modulator based on the current signals in the first homodyne detector and the second homodyne detector. When the sum of the DC parts of the signal currents at the output end of the first homodyne detector and the DC part of the signal current at the output end of the second homodyne detector is not zero, the control chip regulates the first phase modulator through the current source until the sum of the DC parts of the signal currents at the output end of the first homodyne detector and the DC part of the signal current at the output end of the second homodyne detector is zero.

[0027] Further, the multi-output quantum random number generation method further includes:

[0028] The control chip collects two sets of random numbers generated by the post-processing chip, respectively intercepts random number segments of the same length, and determines whether the two random number segments are consistent;

[0029] When the two random number segments are consistent, they are respectively output through two output ports;

[0030] When the two random number segments are inconsistent, the output of the two-way random numbers is interrupted, and then the second phase modulator and the third phase modulator are regulated by a current source until the two random number segments are consistent, and the output of the two-way random numbers is restored.

[0031] Generally speaking, compared with the prior art, the above technical solution conceived by this application can achieve the following beneficial effects:

[0032] Through the optical path design, the technical solution of this application obtains two optical signals with the same randomness at the entropy source level, and obtains quantum noise by detecting these two optical signals respectively and converts them into the same quantum random numbers. The whole process does not require the copying of electronic data, retains the true randomness of the two entropy sources, and reduces the risk of data being stolen and tampered with. Description of the Drawings

[0033] To more clearly illustrate the technical solutions in this embodiment or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 Schematic diagram of a multi-channel output quantum random number generation device provided by an embodiment of this application;

[0035] Figure 2 Schematic diagram of a multi-channel output quantum random number generation device provided by another embodiment of this application;

[0036] Figure 3 Schematic diagram of a cascaded beam splitter module provided by an embodiment of this application;

[0037] Figure 4 Schematic diagram of the fiber connection between the cascaded beam splitter module and the first homodyne detector and the second homodyne detector provided by an embodiment of this application;

[0038] Figure 5 Schematic diagram of the composition of the first signal processing module and the second signal processing module provided by an embodiment of this application;

[0039] Figure 6 Schematic diagram of the composition and connection relationship of the control module provided by an embodiment of this application

[0040] Figure 7 Schematic diagram of the process of a multi-channel output quantum random number generation method provided by an embodiment of this application. Detailed Embodiments

[0041] To make the above objects, features, and advantages of the present application more apparent and understandable, the embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

[0042] In the following description, many specific details are set forth in order to fully understand the present application. However, the present application may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0043] The multi-output quantum random number generation device and the multi-output quantum random number generation method implemented by the present application will be introduced in detail below in conjunction with specific embodiments.

[0044] Specifically, the present application proposes a multi-output quantum random number generation device, as Figure 1 shown, which includes a laser light source, a cascaded beam splitter module, a first homodyne detector, a second homodyne detector, a first signal processing module, a second signal processing module, and a control module.

[0045] The cascaded beam splitter module includes a first beam splitter, a second beam splitter, and a third beam splitter. The first beam splitter, the second beam splitter, and the third beam splitter are all 2x2 optical beam splitters, and each includes an upper input end, a lower input end, an upper output end, and a lower output end. The upper input end of the first beam splitter is connected to the laser light source to input the eigenlight, and the lower input end of the first beam splitter is left vacant, that is, the input vacuum state. The lower input end of the second beam splitter is connected to the upper output end of the first beam splitter, and the upper input end of the third beam splitter is connected to the lower output end of the first beam splitter. The upper output end and the lower output end of the second beam splitter and the upper output end and the lower output end of the third beam splitter constitute the four output ends of the cascaded beam splitter module. After the cascaded beam splitter module, a first homodyne detector and a second homodyne detector are connected.

[0046] The two input ends of the first homodyne detector are respectively connected to the upper output end of the second beam splitter and the upper output end of the third beam splitter, and the two input ends of the second homodyne detector are respectively connected to the lower output end of the second beam splitter and the lower output end of the third beam splitter. As Figure 1 shown, a cross connection is formed between the second beam splitter, the third beam splitter and the first homodyne detector, the second homodyne detector.

[0047] The first signal processing module is connected to the output end of the first homodyne detector and is used to process and convert the signal output by the first homodyne detector into a first original random number sequence. The second signal processing module is connected to the second homodyne detector and is used to process and convert the signal output by the second homodyne detector into a second original random number sequence. Specifically, the signals output by the first homodyne detector and the second homodyne detector can be high and low levels. It is set that the high level is 1 and the low level is 0. According to this rule, the high and low level sequences output by the first homodyne detector and the second homodyne detector are converted into the first original random number sequence and the second original random number sequence.

[0048] After the first signal processing module and the second signal processing module, a control module is connected. Specifically, the control module is connected to the output ends of the first signal processing module and the second signal processing module and is used to perform post-processing, sampling inspection, extraction on the first original random number sequence and the second original random number sequence and output them through two output ports respectively. The control module is also connected to the first beam splitter, the second beam splitter, and the third beam splitter and is used to control the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:50. Post-processing is to consider that some classical noises will inevitably be introduced in the foregoing process, and at the same time, it is also considered that the original quantum noise generally cannot meet the characteristic of uniform distribution after being sampled. Therefore, an algorithm post-processing process (Post-Processing) needs to be performed on the original random number sequence to compress the proportion of classical noise data therein and optimize the final random number distribution. The mainstream post-processing algorithms include logical exclusive OR (XOR), truncation method (m-LSB), Toeplitz matrix algorithm, and Trevisan extraction algorithm, etc. Among them, the Toeplitz matrix algorithm is a random number post-processing algorithm proven to be secure by information theory. In this application, the Toeplitz matrix algorithm is preferably used in the post-processing process. Sampling inspection is to consider that the first original random number sequence and the second original random number sequence may have inconsistent results in some random number segments due to abnormal conditions. Therefore, before the two groups of random numbers are finally output, the first original random number sequence and the second original random number sequence are sampled and inspected according to a certain field length and compared. If they are exactly the same, they are normally output. If they are inconsistent, they are discarded.

[0049] The control module is also connected to the first beam splitter, the second beam splitter, and the third beam splitter and is used to control the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:50. When the sampled first original random number sequence and the second original random number sequence are different, the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter are adjusted so that the first original random number sequence and the second original random number sequence return to the same result.

[0050] In other embodiments of this application, such as Figure 2As shown in the figure, the first homodyne detector includes a first photodetector, a third photodetector, a first current differentiator, and a first transimpedance amplifier. The first photodetector is connected to the upper output end of the second beam splitter, and the third photodetector is connected to the upper output end of the third beam splitter. The input ends of the first photodetector and the third photodetector serve as the two input ends of the first homodyne detector. The output ends of the first photodetector and the third photodetector are both connected to the first current differentiator, the output end of the first current differentiator is connected to the first transimpedance amplifier, and the output end of the first transimpedance amplifier serves as the output end of the first homodyne detector. The second homodyne detector includes a second photodetector, a fourth photodetector, a second current differentiator, and a second transimpedance amplifier. The second photodetector is connected to the lower output end of the second beam splitter, and the fourth photodetector is connected to the lower output end of the third beam splitter. The input ends of the second photodetector and the fourth photodetector serve as the two input ends of the second homodyne detector. The output ends of the third photodetector and the fourth photodetector are both connected to the second current differentiator, the output end of the second current differentiator is connected to the second transimpedance amplifier, and the output end of the second transimpedance amplifier serves as the output end of the second homodyne detector.

[0051] The first current differentiator receives the photocurrent signals of the first photodetector and the third photodetector and generates a difference signal of the two photocurrents. The first photodetector and the third photodetector are in a series connection relationship. According to Kirchhoff's current law, a difference signal of the two photocurrents can be obtained. The obtained photocurrent difference signal has both an AC component and a DC component. The high-frequency AC component carries quantum noise information and can reflect the quadrature amplitude or quadrature phase information of the signal light. When the signal light is in the vacuum state, what is reflected is the quadrature component of the vacuum state, and the DC component is used to detect the intensity of the incident light. Similarly, the second current differentiator receives the photocurrent signals of the second photodetector and the fourth photodetector and generates a difference signal of the two photocurrents.

[0052] The output end of the first current differentiator is connected to the first transimpedance amplifier, which is used to amplify and convert the difference signal of the two photocurrents into a photovoltage signal. The photocurrent difference signal converted by the photodiode is very weak and requires an amplifier for amplification. In addition to the transimpedance amplifier, a radio frequency amplifier can also be used to achieve the amplification function. The radio frequency amplifier has broadband characteristics, can process a wider frequency signal source, and can well meet the bandwidth characteristics of the balanced homodyne detector. Similarly, the second transimpedance amplifier amplifies and converts the difference signal of the two photocurrents of the second photodetector and the fourth photodetector into a photovoltage signal.

[0053] After the first transimpedance amplifier and the second transimpedance amplifier, a first signal processing module and a second signal processing module are connected. The first signal processing module is connected to the first transimpedance amplifier and is used to process and convert the signal output by the first current differentiator into a first original random number sequence. The second signal processing module is connected to the second transimpedance amplifier and is used to process and convert the signal output by the second current differentiator into a second original random number sequence. The first signal processing module and the second signal processing module can generally be implemented by an FPGA chip. The FPGA chip processes the optical voltage signal sequence to obtain an original random number sequence composed of 0s and 1s.

[0054] In other embodiments of the present application, the first beam splitter, the second beam splitter, and the third beam splitter are all MZ interferometers and respectively include a first phase modulator, a second phase modulator, and a third phase modulator, as Figure 3 shown. The first phase modulator, the second phase modulator, and the third phase modulator are all connected to a control module and are used to control the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:50 according to the adjustment of the control module. The MZ interferometer can be a fiber optic MZ interferometer or can be set as an on-chip MZ interferometer, that is, an MZ interferometer is constructed in the form of on-chip waveguides and on-chip couplers. The phase modulator of the on-chip MZ interferometer can use a thermo-optic phase modulator or an electro-optic phase modulator. The control electrode or control terminal of the phase modulator can be connected to the control module, so as to adjust the phase on the interference arms of the MZ interferometer based on the control signal of the control module, achieving the purpose of controlling the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:50. When the MZ interferometer is set as an on-chip MZ interferometer, the entire cascaded beam splitter module can be integrally fabricated on the substrate through a monolithic integration process, that is, the entire cascaded beam splitter module is an optical chip.

[0055] In other embodiments of the present application, the upper input end of the second beam splitter and the lower input end of the third beam splitter both include a light-shielding layer for shielding the ambient light interference and internal reflection at the upper input end of the second beam splitter and the lower input end of the third beam splitter. By setting the light-shielding layer, there is no input of any optical signal at the upper input end of the second beam splitter and the lower input end of the third beam splitter, and the photons reflected or scattered back from the inside of the second beam splitter and the third beam splitter to their input ends will also be absorbed by the light-shielding layer.

[0056] Figure 4Schematic diagram of the optical fiber connection between the cascaded beam splitter module and the first homodyne detector and the second homodyne detector in another embodiment of the present application. The cascaded beam splitter module is coupled to the first homodyne detector and the second homodyne detector through optical fibers, and the optical fiber lengths between the cascaded beam splitter module and the first homodyne detector and between the cascaded beam splitter module and the second homodyne detector are different. Due to the different optical fiber lengths, the first homodyne detector and the second homodyne detector can be set at different spatial positions or geographical locations, making it possible to obtain the same random numbers at different locations. If the difference in optical fiber length is at the centimeter or meter level, the same random numbers can be obtained on different devices. When the difference in optical fiber length is at the level of hundreds of meters or even kilometers, the same random numbers can be obtained on devices at different locations. The time difference caused by the optical path difference can be compensated according to the transmission distance when extracting the random number output. In this way, the copying of electronic data and the transmission communication over the Internet in the traditional method are avoided, and the data is prevented from being stolen and tampered with.

[0057] In another embodiment of the present application, the first signal processing module includes a first filter and a first analog-to-digital converter, and the second signal processing module includes a second filter and a second analog-to-digital converter. The first filter and the second filter are used to filter out DC signals and classical noise, and the first analog-to-digital converter and the second analog-to-digital converter are used to convert analog signals into digital signals, as Figure 5 shown. The classical noise cannot be completely filtered out in this step, and it can be further removed in the subsequent post-processing process. When the difference in optical fiber length is at the centimeter or meter level, the first homodyne detector and the second homodyne detector are set at the same location. The first filter and the second filter can be integrated in the same device, or the integration of the first filter and the second filter can be achieved through a dual-channel filter. Similarly, the integration of the first analog-to-digital converter and the second analog-to-digital converter can be achieved through a dual-channel analog-to-digital converter.

[0058] In another embodiment provided by the present application, the control module includes a post-processing chip, a control chip, and a current source, as Figure 6 shown. The post-processing chip is connected to the first signal processing module and the second signal processing module. The control module performs post-processing on the first original random number sequence and the second original random number sequence through the post-processing chip, such as post-processing with the Toeplitz matrix algorithm, to obtain uniformly distributed random numbers. The current source is simultaneously connected to the first phase modulator, the second phase modulator, and the third phase modulator. The control chip is simultaneously connected to the post-processing chip, the current source, and the output ends of the first homodyne detector and the second homodyne detector. The control module performs sampling inspection, extraction, and output on the random numbers obtained through post-processing through the control chip, and controls the current source to adjust the first phase modulator, the second phase modulator, and the third phase modulator based on the current signals of the first homodyne detector and the second homodyne detector.

[0059] Specifically, the control chip is connected to the first homodyne detector and the second homodyne detector. Based on the DC part of the photocurrent in the first homodyne detector and the second homodyne detector, it is determined whether the beam splitting ratio of the first beam splitter remains at 50:50. When it is determined that the beam splitting ratio of the first beam splitter deviates from 50:50, the control chip issues an instruction to the current source, and the current source changes the control currents input to the first phase modulator, the second phase modulator, and the third phase modulator. The phases of the first phase modulator, the second phase modulator, and the third phase modulator change, and their beam splitting ratios change accordingly until the beam splitting ratio returns to 50:50.

[0060] The present application also provides a method for generating multi-channel output quantum random numbers, which is applied to the multi-channel output quantum random number generation device as described above. The process of this method is as Figure 7 shown, and specifically includes:

[0061] The laser light source generates continuous laser light and inputs it into the cascaded beam splitter module through the upper input end of the first beam splitter, that is, the eigenlight is input into the first beam splitter;

[0062] The control module controls the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter to remain at 50:50. The adjustment of the beam splitting ratios of the first beam splitter, the second beam splitter, and the third beam splitter can be carried out dynamically, that is, the control module monitors and adjusts in real time; it can also be turned on regularly, such as when starting up or powering on each time, or turned on for adjustment every once in a while (such as every 1 s).

[0063] The first homodyne detector detects and processes the light intensities output from the upper output end of the second beam splitter and the upper output end of the third beam splitter to convert them into a first voltage signal, and the second homodyne detector detects and processes the light intensities output from the lower output end of the second beam splitter and the lower output end of the third beam splitter to convert them into a second voltage signal;

[0064] The first signal processing module filters and performs analog-to-digital conversion on the first voltage signal to obtain a first raw random number sequence, and the second signal processing module filters and performs analog-to-digital conversion on the second voltage signal to obtain a second raw random number sequence;

[0065] The control module performs post-processing, sampling inspection, and extraction on the first raw random number sequence and the second raw random number sequence to obtain two groups of identical random numbers, which are finally output through two output ports respectively.

[0066] Post-processing is the process of algorithmic post-processing (Post-Processing) on the original random number sequence, compressing the proportion of classical noise data therein and optimizing the final random number distribution. The Toeplitz matrix algorithm is a provably secure random number post-processing algorithm based on information theory. In this application, the Toeplitz matrix algorithm is preferably used in the post-processing process. Before finally outputting two sets of random numbers, the first original random number sequence and the second original random number sequence are sampled at a certain field length and compared. If they are exactly the same, they are normally output; if they are inconsistent, they are discarded.

[0067] In another embodiment of the multi-output quantum random number generation method provided in this application, Reference Figure 2 For explanation with reference to the structure of Figure 2 , the first photodetector, the second photodetector, the third photodetector, and the fourth photodetector detect the light intensities output by the second beam splitter and the third beam splitter and convert them into photocurrents. The first current differentiator performs differential processing on the photocurrents output by the first photodetector and the third photodetector to obtain a first differential current. The first transimpedance amplifier converts and amplifies the first differential current to obtain a first voltage signal. The second current differentiator performs differential processing on the photocurrents output by the second photodetector and the fourth photodetector to obtain a second differential current. The second transimpedance amplifier converts and amplifies the second differential current to obtain a second voltage signal.

[0068] In another embodiment of the multi-output quantum random number generation method provided in this application, for explanation with reference to Figure 3 the structure of Figure 3 , the first beam splitter, the second beam splitter, and the third beam splitter in the multi-output quantum random number generation device are all MZ interferometers and respectively include a first phase modulator, a second phase modulator, and a third phase modulator. The first phase modulator, the second phase modulator, and the third phase modulator are all connected to the control module; the control module includes a post-processing chip, a control chip, and a current source. The post-processing chip is connected to the first signal processing module and the second signal processing module. The current source is simultaneously connected to the first phase modulator, the second phase modulator, and the third phase modulator. The control chip is simultaneously connected to the post-processing chip, the current source, and the output ends of the first homodyne detector and the second homodyne detector.

[0069] The multi-output quantum random number generation method further includes:

[0070] The control module conducts spot checks, extraction, and output on the random numbers obtained through post-processing via a control chip. That is, the functions of "conducting spot checks, extraction, and output on the random numbers obtained through post-processing" are completed by the control chip. Moreover, the control chip also controls the current source to regulate the first phase modulator based on the current signals in the first homodyne detector and the second homodyne detector. When the sum of the DC components of the signal currents at the output terminals of the first homodyne detector and the second homodyne detector is not zero, the control chip regulates the first phase modulator through the current source until the sum of the DC components of the signal currents at the output terminals of the first homodyne detector and the second homodyne detector is zero. The following uses formulas to further explain the above operations.

[0071] Let the DC component of the photocurrent of the first photodetector (such as a photodiode) be i1, and the DC component of the photocurrent of the second photodetector (such as a photodiode) be i3; let the DC component of the photocurrent of the second photodetector (such as a photodiode) be i2, and the DC component of the photocurrent of the fourth photodetector (such as a photodiode) be i4. The DC component of the signal at the output terminal of the first homodyne detector is i1 - i3, the DC component of the signal at the output terminal of the second homodyne detector is i2 - i4, and the sum of the DC components of the signal currents at the output terminals of the first homodyne detector and the second homodyne detector is i1 + i2 - (i3 + i4). When the beam splitting ratio of the first beam splitter is 50:50, i1 + i2 = i3 + i4, so the sum of their DC components is zero. When the sum of their DC components is not zero, the control chip adjusts the beam splitting ratio of the first beam splitter through the current source so that i1 + i2 = i3 + i4, that is, the beam splitting ratio of the first beam splitter is 50:50.

[0072] In another embodiment of the multi-output quantum random number generation method provided in this application, the method further includes:

[0073] The control chip collects two paths of random numbers generated by the post-processing chip, respectively intercepts random number segments of the same length, and determines whether the two random number segments are consistent;

[0074] When the two random number segments are consistent, they are respectively output from two output ports;

[0075] When the two random number segments are inconsistent, the output of the two paths of random numbers is interrupted, and then the second phase modulator and the third phase modulator are regulated through the current source until the two random number segments are consistent, and the output of the two paths of random numbers is restored.

[0076] When the beam splitting ratio of the first beam splitter is 50:50, the reason for the inconsistency of the two randomly selected number segments during the sampling inspection of the control chip is that the beam splitting ratios of the second beam splitter and the third beam splitter deviate from 50:50. At this time, the control chip uses a current source to regulate the second phase modulator and the third phase modulator, so that the beam splitting ratios of the second beam splitter and the third beam splitter are restored to 50:50.

[0077] In addition, the reasons for the inconsistency of the two randomly selected number segments during the sampling inspection may also include the inconsistent performance and detection efficiency of the photodetectors. At this time, the control chip can be connected to four photodetectors. When the two randomly selected number segments during the sampling inspection are inconsistent, the detection efficiency of the photodetectors can be adjusted, so as to achieve the purpose of making the two randomly selected number segments during the sampling inspection consistent.

[0078] In this specification, the various embodiments are described in a progressive, or parallel, or a combination of progressive and parallel manners. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other.

[0079] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that an article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the article or device including the above element.

[0080] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-output quantum random number generator, characterized in that: It includes a laser light source, a cascade beam splitter module, a first zero-beat detector, a second zero-beat detector, a first signal processing module, a second signal processing module and a control module; The cascade beam splitter module includes a first beam splitter, a second beam splitter, and a third beam splitter. The three beam splitters each include an input upper end, an input lower end, an output upper end, and an output lower end. The input upper end of the first beam splitter is connected to a laser light source, and the input lower end of the first beam splitter is left vacant; the input lower end of the second beam splitter is connected to the output upper end of the first beam splitter, and the input upper end of the third beam splitter is connected to the output lower end of the first beam splitter; Two input ends of the first zero-beat detector are respectively connected to the output upper end of the second beam splitter and the output upper end of the third beam splitter, and two input ends of the second zero-beat detector are respectively connected to the output lower end of the second beam splitter and the output lower end of the third beam splitter; The first signal processing module is connected to the output end of the first zero-beat detector, and is used to process the signal output by the first zero-beat detector and convert it into a first original random number sequence. The second signal processing module is connected to the second zero-beat detector, and is used to process the signal output by the second zero-beat detector and convert it into a second original random number sequence. The control module is connected to the output ends of the first signal processing module and the second signal processing module, and is used for post-processing and sampling the first original random number sequence and extracting the second original random number sequence and outputting them respectively through two output ports. The control module is also connected to the first beam splitter, the second beam splitter, and the third beam splitter, and is used to control the beam splitting ratio of the first beam splitter, the second beam splitter, and the third beam splitter to be maintained at 50:

50. When the sampled first original random number sequence and the second original random number sequence are different, the beam splitting ratio of the first beam splitter, the second beam splitter, and the third beam splitter is adjusted so that the first original random number sequence and the second original random number sequence regress to the same result.

2. A multi-output quantum random number generator according to claim 1, characterized in that: The first zero-beat detector includes a first photodetector, a third photodetector, a first current differentiator, and a first transimpedance amplifier. The input ends of the first photodetector and the third photodetector serve as the two input ends of the first zero-beat detector. The output ends of the first photodetector and the third photodetector are both connected to the first current differentiator. The output end of the first current differentiator is connected to the first transimpedance amplifier, and the output end of the first transimpedance amplifier serves as the output end of the first zero-beat detector. The second zero-beat detector includes a second photodetector, a fourth photodetector, a second current differentiator, and a second transimpedance amplifier. The second photodetector is connected to the output lower end of the second beam splitter, the fourth photodetector is connected to the output lower end of the third beam splitter, the input ends of the second photodetector and the fourth photodetector serve as the two input ends of the second zero-beat detector, the output ends of the third photodetector and the fourth photodetector are both connected to the second current differentiator, the output end of the second current differentiator is connected to the second transimpedance amplifier, and the output end of the second transimpedance amplifier serves as the output end of the second zero-beat detector.

3. A multi-output quantum random number generator according to claim 1, characterized in that: The first beam splitter, the second beam splitter, and the third beam splitter are all MZ interferometers and respectively include a first phase modulator, a second phase modulator, and a third phase modulator. The first phase modulator, the second phase modulator, and the third phase modulator are all connected to a control module for controlling the first beam splitter, the second beam splitter, and the third beam splitter to maintain a beam splitting ratio of 50:50 according to the adjustment of the control module.

4. A multi-output quantum random number generator according to claim 1, characterized in that: The first beam splitter, the second beam splitter and the third beam splitter are integrally manufactured on a substrate through a monolithic integration process.

5. A multi-output quantum random number generator according to claim 1, characterized in that: The input upper end of the second beam splitter and the input lower end of the third beam splitter both include a shading layer for shielding the ambient light interference and internal reflection of the input upper end of the second beam splitter and the input lower end of the third beam splitter.

6. A multi-output quantum random number generator according to claim 1, characterized in that: The cascade beam splitter module is coupled to the first zero-beat detector and the second zero-beat detector through optical fiber, and the optical fiber length between the cascade beam splitter module and the first zero-beat detector is different from the optical fiber length between the cascade beam splitter module and the second zero-beat detector.

7. A multi-output quantum random number generator according to claim 1, characterized in that: The control module includes a post-processing chip, a control chip and a current source; The post-processing chip is connected to the first signal processing module and the second signal processing module, and the control module performs post-processing on the first original random number sequence and the second original random number sequence through the post-processing chip to obtain evenly distributed random numbers; the current source is simultaneously connected to the first phase modulator, the second phase modulator, and the third phase modulator, and the control chip is simultaneously connected to the post-processing chip and the current source as well as the output ends of the first zero-beat detector and the second zero-beat detector. The control module performs sampling, extraction and output of the random numbers obtained through the control chip, and controls the current source based on the current signals in the first zero-beat detector and the second zero-beat detector to regulate the first phase modulator, the second phase modulator, and the third phase modulator.

8. A multi-output quantum random number generation method, characterized in that: Applied to a multi-output quantum random number generating device as claimed in any one of claims 1 to 7, the method comprising: The laser light source generates continuous laser light and inputs the continuous laser light into the cascade beam splitter module through the upper input end of the first beam splitter; The control module controls the first beam splitter, the second beam splitter, and the third beam splitter to maintain a beam splitting ratio of 50:50; The first zero-beat detector detects the light intensity output from the upper output end of the second beam splitter and the upper output end of the third beam splitter and processes and converts the light intensity into a first voltage signal, and the second zero-beat detector detects the light intensity output from the lower output end of the second beam splitter and the lower output end of the third beam splitter and processes and converts the light intensity into a second voltage signal; The first signal processing module filters and performs analog-to-digital conversion on the first voltage signal to obtain a first original random number sequence, and the second signal processing module filters and performs analog-to-digital conversion on the second voltage signal to obtain a second original random number sequence; The control module includes a post-processing chip, a control chip and a current source. The control module performs post-processing and sampling on the first original random number sequence and the second original random number sequence to obtain two groups of identical random numbers, and finally outputs them respectively through two output ports; The control chip collects two random numbers generated by the post-processing chip, respectively intercepts random number segments of the same length, and determines whether the two random number segments are consistent; when the two random number segments are consistent, they are output by two output ports respectively; when the two random number segments are inconsistent, the output of the two random numbers is interrupted, and the second phase modulator and the third phase modulator are regulated by the current source until the two random number segments are consistent, and the output of the two random numbers is restored.

9. A multi-output quantum random number generation method according to claim 8, characterized in that: The first beam splitter, the second beam splitter, and the third beam splitter are all MZ interferometers and respectively include a first phase modulator, a second phase modulator, and a third phase modulator, and the first phase modulator, the second phase modulator, and the third phase modulator are all connected to the control module; the post-processing chip is connected to the first signal processing module and the second signal processing module, the current source is simultaneously connected to the first phase modulator, the second phase modulator, and the third phase modulator, and the control chip is simultaneously connected to the post-processing chip and the current source as well as the output ends of the first zero-beat detector and the second zero-beat detector; The method further comprises: The control module performs sampling, extraction and output of the random numbers obtained through post-processing through the control chip, and the control chip also controls the current source to regulate the first phase modulator based on the current signals in the first zero-beat detector and the second zero-beat detector. When the sum of the DC part of the signal current at the output end of the first zero-beat detector and the DC part of the signal current at the output end of the second zero-beat detector is not zero, the control chip regulates the first phase modulator through the current source until the sum of the DC part of the signal current at the output end of the first zero-beat detector and the DC part of the signal current at the output end of the second zero-beat detector is zero.

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