A quantum random number generation system based on polarization for laser phase fluctuations

Abstract

The present invention discloses a quantum random number generation system based on polarization of laser phase fluctuations, which relates to the field of quantum random numbers. The system includes a pulsed laser module, an optical intensity stabilization module, an interference module, a detection module, an analog-to-digital conversion module, and a data post-processing module connected in sequence. The pulsed laser module, the optical intensity stabilization module, and the interference module are connected in sequence through polarization-maintaining optical fibers. The pulsed laser module is used to prepare two optical pulses, one of which is coupled into the fast axis of the polarization-maintaining optical fiber, and the other is coupled into the slow axis of the polarization-maintaining optical fiber. The interference module rotates the polarization directions of the two optical pulses and then couples them to achieve interference. The present invention uses two independent lasers for interference measurement, replacing the laser self-interference technology in the current technology; the present invention selects a distributed feedback laser, which can achieve good interference effects; the present invention realizes interference measurement through the method of rotational coupling and can eliminate the influence of polarization fluctuations on the interference effect.

Description

Technical Field

[0001] The present invention relates to the field of quantum random numbers, and particularly to a quantum random number generation system based on polarization-induced laser phase fluctuations. Background Art

[0002] Random numbers are fundamental resources in science and engineering and have important applications in simulation and cryptography. The generation of classical random numbers often relies on deterministic algorithms or predictable complex physical phenomena. Random number generators of this type are easy to use, but there are also security threats during the random number generation process. The random numbers generated in these ways are called pseudo-random numbers, which cannot meet the security requirements in high-security applications. In contrast, a quantum random number generator can be called a true random number generator, and the random numbers it outputs are obtained by measuring variables with intrinsic random characteristics in a quantum physical system.

[0003] Currently, quantum random number generation is one of the most mature technologies in quantum technology, and there are various generation methods available. For example, early practical quantum random number generators mostly adopted the single-photon scheme. In recent years, the laser phase fluctuation scheme and the vacuum state scheme have become research hotspots in quantum random numbers. The common feature of these two schemes is that they use high-speed photodetectors to replace the previous single-photon detectors, so that the random number generation rate is no longer limited by the saturation counting rate of single-photon detectors and reaches the order of Gbps.

[0004] The current technology "A quantum random number generation device, method and generator for suppressing noise (CN202010198459.2)" uses a narrow-linewidth laser as an entropy source, performs self-interference through an unbalanced Mach-Zehnder interferometer, and uses the method of homodyne detection or subtraction after analog-to-digital conversion to eliminate the optical intensity bias term in the measured value, which has the effect of suppressing laser intensity noise. However, there are also some problems with this technology, such as:

[0005] 1. The laser self-interference method adopted by this technology will cause phase correlation between front and rear pulses, affecting the autocorrelation coefficient of the original data. When the original data generation rate is relatively high (about 50 Mbps), the autocorrelation coefficient of adjacent terms will increase significantly, which will limit the quality and generation rate of random numbers;

[0006] 2. In order to reduce the correlation between adjacent pulses, the optical path difference between the two arms of the interferometer needs to be greater than the coherence length of light, which will make the device complex and is not conducive to integration;

[0007] 3. This technology uses an SFP laser or an SLED light source as an entropy source. The SFP laser is a commonly used device in optical communication and can emit high-frequency optical pulses at a relatively low cost. However, the central frequency of the light itself is unstable, and the linewidth is also relatively wide, making it impossible to achieve a good interference effect. The SLED spectrum is relatively wide, and the self-interference effect is also relatively poor. The SFP laser or the SLED light source is not an ideal entropy source in the laser phase fluctuation scheme.

[0008] The current technology "A Quantum Random Number Generation Method and System Based on Post-Detection Subtraction" (CN202210671742.1) uses two lasers with similar frequencies for interference and combines appropriate data post-processing methods to solve the correlation problem between adjacent measurements. This technology also separates quantum noise and classical noise during the data post-processing process, improving the minimum entropy. However, at the same time, this technology also has some problems. For example, this technology does not consider the impact of polarization fluctuations on the interference result, and the best interference effect can only be achieved when the polarization directions of the two beams of light are exactly the same. In a high-precision optoelectronic system, the single-mode fiber needs to be polarization-calibrated every few tens of minutes. Especially in an integrated quantum random number generator, the bending and jitter of the fiber will have a non-negligible impact on polarization. Summary of the Invention

[0009] Object of the Invention: The object of the present invention is to provide a quantum random number generation system based on polarization of laser phase fluctuation, which solves a series of problems brought by the current laser self-interference method, the problem of improper selection of the ideal entropy source in the laser phase fluctuation scheme, and the problem of the impact of polarization fluctuations during the interference process. The present invention uses two independent lasers for interference measurement, replacing the laser self-interference technology in the current technology; the present invention selects a distributed feedback laser, which can achieve a good interference effect; the present invention realizes the interference measurement by using the method of rotational coupling in a polarization-maintaining optical path, which can eliminate the impact of polarization fluctuations on the interference effect.

[0010] Technical Solution: A quantum random number generation system based on polarization of laser phase fluctuation, which includes a pulsed laser module, an optical intensity stabilization module, an interference module, a detection module, an analog-to-digital conversion module, and a data post-processing module connected in sequence. The pulsed laser module, the optical intensity stabilization module, and the interference module are connected in sequence through polarization-maintaining optical fibers;

[0011] The pulsed laser module is used to prepare two optical pulses, one of which is coupled into the fast axis of the polarization-maintaining optical fiber, denoted as The other optical pulse is coupled into the slow axis of the polarization-maintaining optical fiber, denoted as where μ and υ respectively represent the optical intensities of the two optical pulses, and i is the imaginary unit, is the phase difference between the two optical pulses;

[0012] The light intensity stabilization module is used for the attenuation of two optical pulses;

[0013] The interference module rotates the polarization directions of the two optical pulses and then couples them, so that the optical pulses transmitted along the fast axis of the polarization-maintaining fiber interfere with the optical pulses transmitted along the slow axis of the polarization-maintaining fiber;

[0014] The detection module converts the optical signal obtained after interference into an analog electrical signal;

[0015] The analog-to-digital conversion module converts the analog electrical signal into a digital electrical signal;

[0016] The data post-processing module processes the original data.

[0017] Furthermore, the two optical pulses prepared by the pulsed laser module are high extinction ratio optical pulses. The duty cycles and frequencies of the two optical pulses are the same, and the optical frequency error between the two optical pulses is within the GHz order of magnitude. The duty cycles of the two optical pulses prepared are both 50%. The light intensity stabilization module is used for the attenuation of the two optical pulses until the light intensity difference between the two attenuated optical pulses is within 5%.

[0018] Furthermore, the pulsed laser module includes a first pulsed laser and a second pulsed laser. The light intensity stabilization module includes a first optical attenuator and a second optical attenuator. The interference module includes a polarization-maintaining beam splitter and a polarization beam splitter connected by a polarization-maintaining fiber;

[0019] The first pulsed laser, the first optical attenuator and the polarization-maintaining beam splitter are sequentially connected by a polarization-maintaining fiber. The second pulsed laser, the second optical attenuator and the polarization-maintaining beam splitter are sequentially connected by a polarization-maintaining fiber;

[0020] The first pulsed laser and the second pulsed laser are used to prepare two high extinction ratio optical pulses and send the optical pulses to the corresponding optical attenuators;

[0021] The first optical attenuator and the second optical attenuator attenuate the received optical pulses, and the attenuated optical pulses are sent to the polarization-maintaining beam splitter;

[0022] The polarization-maintaining beam splitter is a polarization-maintaining input / output beam splitter, which is used to couple the two optical pulses into a polarization-maintaining fiber;

[0023] The polarization beam splitter is used to rotate the polarization directions of the two optical pulses and then achieve interference.

[0024] Furthermore, the polarization beam splitter is a 45° polarization beam splitter, and the polarization directions of the two optical pulses are rotated by 45°. The 45° rotation matrix is expressed as:

[0025]

[0026] Further, the detection module includes a first photodetector, and the first photodetector is connected to the polarization beam splitter. The optical signal obtained after the polarization beam splitter realizes interference is expressed as:

[0027]

[0028] The first photodetector is used to convert the optical signal obtained after interference into an analog electrical signal, and the intensity of the converted analog electrical signal is expressed as:

[0029]

[0030] where L 1 represents the electrical noise of the first photodetector, and B is the conversion ratio of the first photodetector;

[0031] The analog-to-digital conversion module is an analog-to-digital converter;

[0032] The data post-processing module is a computer.

[0033] Further, the detection module includes a second photodetector, a third photodetector and a differential amplifier. The second photodetector is connected to the polarization beam splitter and the differential amplifier, and the third photodetector is connected to the polarization beam splitter and the differential amplifier. The optical signal obtained after the polarization beam splitter realizes interference is expressed as:

[0034]

[0035] The second photodetector and the third photodetector are used to convert the optical signal obtained after interference into an analog electrical signal, and the intensity of the converted analog electrical signal is expressed as:

[0036]

[0037]

[0038] where L 2 and L 3 respectively represent the electrical noise of the second photodetector and the third photodetector, and C is the conversion ratio of the second photodetector and the third photodetector;

[0039] The analog electrical signals are subtracted, and the difference value is expressed as:

[0040]

[0041] where ΔL represents the difference between the electrical noises of the second photodetector and the third photodetector;

[0042] The analog-to-digital conversion module is an analog-to-digital converter;

[0043] The data post - processing module is a computer.

[0044] Furthermore, the pulsed laser module further includes a first temperature control device and a second temperature control device. The first temperature control device is connected to the first pulsed laser, and the first temperature control device is used to adjust the center frequency of the first pulsed laser. The second temperature control device is connected to the second pulsed laser, and the second temperature control device is used to adjust the center frequency of the second pulsed laser.

[0045] Advantages of the present invention:

[0046] 1. The present invention uses two independent lasers for interference measurement. Compared with the current technical solution, it no longer requires the use of an interferometer, nor does it require controlling the stability of the arm - length difference of the interferometer through a temperature control or feedback system, which simplifies the system structure and is conducive to the realization of system integration;

[0047] 2. In the present invention, the two independent lasers adopt a pulse + pulse working mode, eliminating the correlation between adjacent pulses, improving the quality of the original data, and also making the self - coherence coefficient no longer limited by the sampling interval at the detection end, thereby increasing the generation rate of random numbers;

[0048] 3. The present invention selects a distributed feedback laser and controls it through a pulsed drive current. The distributed feedback laser has a narrow linewidth and good stability, and can achieve a good interference effect;

[0049] 4. The present invention realizes interference measurement by using the method of rotational coupling in a polarization - maintaining optical path. On the premise of eliminating the influence of polarization fluctuations on the interference effect, it realizes the generation of quantum random numbers, improves the randomness of the original data, and can obtain a higher random number generation rate under the same post - processing rate. Brief Description of the Drawings

[0050] Figure 1 It is a schematic structural diagram of a quantum random number generation system based on polarization - based laser phase fluctuations of the present invention;

[0051] Figure 2 It is a schematic structural diagram of Embodiment 1;

[0052] Figure 3 It is a schematic structural diagram of Embodiment 2. Detailed Embodiments

[0053] The following further describes the present invention with reference to the drawings and embodiments:

[0054] A method for a quantum random number generation system based on polarization - based laser phase fluctuations, the method comprising the following steps:

[0055] Step 1: Prepare two optical pulses with a high extinction ratio. The duty cycles and frequencies of the two optical pulses are the same, and the optical frequency error between the two optical pulses is within the GHz order of magnitude. The duty cycle of both optical pulses is 50%. The duty cycle and frequency of the optical pulses are determined by the driving current for pulse generation. The two optical pulses are transmitted through polarization-maintaining fibers for attenuation. One of the optical pulses is coupled into the fast axis of the polarization-maintaining fiber, and the other optical pulse is coupled into the slow axis of the polarization-maintaining fiber. The optical pulses can be prepared by a pulsed laser. In the present invention, a distributed feedback laser can be selected and controlled by a pulsed driving current. To eliminate the influence of polarization fluctuations on the interference effect, polarization-maintaining fibers are used to transmit the optical pulses in the present invention. The use of polarization-maintaining fibers ensures that the polarization direction of the optical pulses does not change during transmission;

[0056] Step 2: Attenuate the two optical pulses until the optical intensity difference between the two attenuated optical pulses is within 5%, so that the intensities of the two optical pulses are similar. The attenuated optical pulses are transmitted through polarization-maintaining fibers for the interference step;

[0057] Step 3: Adjust the delay time of the two optical pulses so that the two optical pulses reach the interference device simultaneously. The interference device rotates the polarization directions of the two optical pulses and then couples them. The rotation angle is 45°, so that the optical pulse transmitted through the fast axis of the polarization-maintaining fiber interferes with the optical pulse transmitted through the slow axis of the polarization-maintaining fiber;

[0058] Step 4: Convert the optical signal obtained after interference into an analog electrical signal, and then convert the analog electrical signal into a digital electrical signal;

[0059] Step 5: Use a method with strict security proof for random number extraction, such as Toeplitz matrix extraction, to obtain quantum random numbers;

[0060] Step 6: Detect the randomness of the random numbers through randomness tests of standards such as NIST.

[0061] Among them, when converting the analog electrical signal into a digital electrical signal, first sample the analog electrical signal. The sampling frequency of the analog-to-digital conversion is equal to the frequency of the optical pulse. Then, use a finite number of amplitude values to quantize the sampling result, and perform binary coding on the quantization result. An analog-to-digital converter can be selected to complete the analog-to-digital conversion.

[0062] Take a set of analog electrical signal data with a data volume of a, remove the maximum and minimum values of b% of them, use an n-bit analog-to-digital converter, and evenly divide the remaining part into 2 n parts according to the voltage distribution range through the analog-to-digital converter. Each analog electrical signal is converted into any binary number between 000…00 and 111…11 according to its signal strength. In the present invention, a is selected as 100M, b is selected as 0.5, and n is selected as 8.

[0063] In step 4, the analog electrical signal needs to exclude the influence of classical noise. The probability distribution of the intensity of the analog electrical signal after excluding the influence of classical noise follows a standard arcsine curve distribution, which is expressed as:

[0064]

[0065] where the boundary values of the standard arcsine distribution curve are A;

[0066] where q is the intensity of the analog electrical signal.

[0067] As Figure 1 shown, a quantum random number generation system based on polarization-induced laser phase fluctuations according to the present invention includes a pulsed laser module, an optical intensity stabilization module, an interference module, a detection module, an analog-to-digital conversion module, and a data post-processing module connected in sequence. In order to exclude the influence of polarization fluctuations on the interference effect, the present invention uses polarization-maintaining optical fibers to transmit optical pulses. The use of polarization-maintaining optical fibers ensures that the polarization direction of the optical pulses does not change during transmission. The pulsed laser module, the optical intensity stabilization module, and the interference module are connected in sequence by polarization-maintaining optical fibers. The interference module and the detection module are connected by an optical fiber. The detection module, the analog-to-digital conversion module, and the data post-processing module are connected in sequence by wires;

[0068] The pulsed laser module is used to prepare two optical pulses with a high extinction ratio. The duty cycles and frequencies of the two optical pulses are the same. The duty cycles and frequencies of the optical pulses are determined by the drive current of the pulsed laser module. The optical frequency error between the two optical pulses is within the GHz order of magnitude. The duty cycles of the two prepared optical pulses are both 50%. One of the optical pulses is coupled into the fast axis of the polarization-maintaining optical fiber, denoted as The other optical pulse is coupled into the slow axis of the polarization-maintaining optical fiber, denoted as where μ and υ respectively represent the optical intensities of the two optical pulses, and i is the imaginary unit, is the phase difference between the two optical pulses, and |> is the right ket representation in the Dirac symbol.

[0069] The optical intensity stabilization module is used to attenuate the two optical pulses until the optical intensity difference between the two attenuated optical pulses is within 5%. The optical intensity stabilization module will receive the optical pulses emitted by the pulsed laser module, detect the optical intensity of the optical pulses, compare the detected optical intensity with the set original optical intensity, and regulate the intensity of the optical pulses by an active feedback method;

[0070] The interference module rotates the polarization directions of the two optical pulses and then couples them. The rotation angle is 45°, so that the optical pulse transmitted through the fast axis of the polarization-maintaining optical fiber interferes with the optical pulse transmitted through the slow axis of the polarization-maintaining optical fiber. The intensity of the optical signal obtained after interference is controlled by the phase difference between the two optical pulses. In order to exclude the influence of polarization fluctuations on the interference effect, the present invention uses polarization-maintaining optical fibers to transmit optical pulses;

[0071] The detection module converts the optical signal obtained after interference into an analog electrical signal. The detection module can detect the intensity of the optical signal output by the interference module. To ensure the accuracy of detection, the detection module requires good linearity, a wide detection range, and low background noise;

[0072] The analog-to-digital conversion module converts the analog electrical signal into a digital electrical signal, and the threshold of the digital electrical signal can be adjusted according to the intensity distribution of the analog electrical signal;

[0073] The data post-processing module is used to process the original data using a randomness extraction algorithm that has been strictly proven for information security. The data post-processing module requires high speed and good stability.

[0074] Embodiment 1

[0075] As Figure 2 shown, the pulsed laser module includes a first pulsed laser and a second pulsed laser, the optical intensity stabilization module includes a first optical attenuator and a second optical attenuator, and the interference module includes a polarization beam splitter and a polarization beam combiner connected by polarization-maintaining optical fibers.

[0076] The first pulsed laser, the first optical attenuator, and the polarization beam splitter are sequentially connected by polarization-maintaining optical fibers, and the second pulsed laser, the second optical attenuator, and the polarization beam splitter are sequentially connected by polarization-maintaining optical fibers.

[0077] The first pulsed laser and the second pulsed laser are used to generate two optical pulses with a high extinction ratio and send the optical pulses to the corresponding optical attenuators. The duty cycles and frequencies of the two optical pulses are the same, and the duty cycles and frequencies of the optical pulses are determined by the drive current of the pulsed laser. The optical pulses emitted by the laser include the influence of spontaneous emission and stimulated emission. When the drive voltage is close to the emission threshold, the generated laser optical intensity is weak, the laser linewidth is wide, and the phase fluctuation is the most obvious. In the present invention, the pulsed laser should be in this working state. The present invention can select a distributed feedback laser and control it through a pulsed drive current.

[0078] The first optical attenuator and the second optical attenuator attenuate the received optical pulses until the optical intensity difference between the two attenuated optical pulses is within 5%, and the attenuated optical pulses are sent to the polarization beam splitter.

[0079] The polarization beam splitter is a polarization-maintaining input / output beam splitter, which is used to couple two optical pulses into a polarization-maintaining optical fiber.

[0080] The polarization beam combiner is used to couple the two optical pulses after rotating their polarization directions, so that the optical pulse transmitted along the fast axis of the polarization-maintaining optical fiber interferes with the optical pulse transmitted along the slow axis of the polarization-maintaining optical fiber.

[0081] The polarization beam splitter is a 2×1 polarization beam splitter with a 45° angle. It has 2 input ports and 1 output port. The polarization directions of the two optical pulses are rotated by 45°. The 45° rotation matrix is expressed as:

[0082]

[0083] After rotation, 50% of the optical pulses input from the two input ports will be coupled into the output port respectively to achieve interference. The optical signal obtained after the polarization beam splitter realizes interference is expressed as:

[0084]

[0085] The detection module includes a first photodetector. The first photodetector is fiber-connected to the polarization beam splitter. The first photodetector is used to convert the optical signal obtained after interference into an analog electrical signal. The intensity of the converted analog electrical signal is expressed as:

[0086]

[0087] Among them, L 1 represents the electrical noise of the first photodetector, and B is the conversion ratio of the first photodetector.

[0088] The photodetector of the present invention can be a PIN photodiode or an avalanche photodiode.

[0089] The analog-to-digital conversion module is an analog-to-digital converter. The analog-to-digital converter is wire-connected to the first photodetector. The analog-to-digital converter is used to convert the analog electrical signal into a digital electrical signal. The analog-to-digital conversion module of the present invention can also use an oscilloscope.

[0090] The data post-processing module is a computer. The computer is wire-connected to the analog-to-digital converter and is used for processing the original data.

[0091] The pulsed laser module further includes a first temperature control device and a second temperature control device. The first temperature control device is connected to the first pulsed laser. The first temperature control device is used to adjust the center frequency of the first pulsed laser. The second temperature control device is connected to the second pulsed laser. The second temperature control device is used to adjust the center frequency of the second pulsed laser. The temperature control device of the present invention can use an active feedback semiconductor refrigerator.

[0092] Embodiment 2

[0093] As Figure 3 shown, the pulsed laser module includes a first pulsed laser and a second pulsed laser. The optical intensity stabilization module includes a first optical attenuator and a second optical attenuator. The interference module includes a polarization beam splitter and a polarization beam splitter connected by polarization-maintaining optical fibers.

[0094] The first pulsed laser, the first optical attenuator and the polarization-maintaining beam splitter are sequentially connected by polarization-maintaining optical fibers, and the second pulsed laser, the second optical attenuator and the polarization-maintaining beam splitter are sequentially connected by polarization-maintaining optical fibers.

[0095] The first pulsed laser and the second pulsed laser are used to generate two optical pulses with a high extinction ratio and send the optical pulses to the corresponding optical attenuators. The duty cycles and frequencies of the two optical pulses are the same, and the duty cycles and frequencies of the optical pulses are determined by the drive current of the pulsed lasers. The optical pulses emitted by the lasers include the influence of spontaneous emission and stimulated emission. When the drive voltage is close to the emission threshold, the generated laser light intensity is weak, the laser linewidth is wide, and the phase fluctuation is the most obvious. In the present invention, the pulsed lasers should be in this working state. The present invention can select distributed feedback lasers and control them through pulsed drive currents.

[0096] The first optical attenuator and the second optical attenuator attenuate the received optical pulses until the optical intensity difference between the two attenuated optical pulses is within 5%, and the attenuated optical pulses are sent to the polarization-maintaining beam splitter.

[0097] The polarization-maintaining beam splitter is a polarization-maintaining input-output beam splitter, which is used to couple two optical pulses into a single polarization-maintaining optical fiber.

[0098] The polarization beam splitter is used to couple the two optical pulses after rotating their polarization directions, so that the optical pulses transmitted along the fast axis of the polarization-maintaining optical fiber interfere with the optical pulses transmitted along the slow axis of the polarization-maintaining optical fiber.

[0099] The polarization beam splitter is a 45° 2×2 polarization beam splitter, with 2 input ports and 2 output ports. The polarization directions of the two optical pulses are rotated by 45°. The 45° rotation matrix is expressed as:

[0100]

[0101] After rotation, 50% of the optical pulses input from the two input ports will be coupled into the two output ports respectively to achieve interference. The optical signal obtained after interference by the polarization beam splitter is expressed as:

[0102]

[0103] The detection module includes a second photodetector, a third photodetector, and a differential amplifier. The second photodetector is fiber-connected to the polarization beam splitter, and the second photodetector is wire-connected to the differential amplifier. The third photodetector is fiber-connected to the polarization beam splitter, and the third photodetector is wire-connected to the differential amplifier. The intensities of the analog electrical signals output by the second photodetector and the third photodetector are proportional to the intensities of the optical signals obtained after interference. The differential amplifier subtracts the analog electrical signals output by the two photodetectors to eliminate the light intensity bias part, so that the bias elimination process is no longer required in the data post-processing, simplifying the post-processing.

[0104] The second photodetector and the third photodetector are used to convert the optical signal obtained after interference into an analog electrical signal. The intensity of the converted analog electrical signal is expressed as:

[0105]

[0106]

[0107] Where L 2 , L 3 represent the electrical noises of the second photodetector and the third photodetector respectively, and C is the conversion ratio of the second photodetector and the third photodetector.

[0108] The photodetector of the present invention can be a PIN photodiode or an avalanche photodiode.

[0109] Subtract the analog electrical signals. The difference is expressed as:

[0110]

[0111] Where ΔL represents the difference in electrical noise between the second photodetector and the third photodetector;

[0112] The analog-to-digital conversion module is an analog-to-digital converter. The analog-to-digital converter is wire-connected to the differential amplifier and is used to convert the analog electrical signal into a digital electrical signal. The analog-to-digital conversion module of the present invention can also use an oscilloscope.

[0113] The data post-processing module is a computer. The computer is wire-connected to the analog-to-digital converter and is used for processing the original data.

[0114] The pulsed laser module also includes a first temperature control device and a second temperature control device. The first temperature control device is connected to the first pulsed laser and is used to adjust the center frequency of the first pulsed laser. The second temperature control device is connected to the second pulsed laser and is used to adjust the center frequency of the second pulsed laser. The temperature control device of the present invention can use an active feedback semiconductor cooler.

Claims

1. A quantum random number generation system based on polarization of laser phase fluctuations, characterized in that, the system includes a pulsed laser module, an optical intensity stabilization module, an interference module, a detection module, an analog-to-digital conversion module and a data post-processing module connected in sequence. The pulsed laser module, the optical intensity stabilization module and the interference module are connected in sequence through polarization-maintaining optical fibers; The pulsed laser module is used to generate two optical pulses. One of the optical pulses is coupled into the fast axis of the polarization-maintaining fiber, denoted as , and the other optical pulse is coupled into the slow axis of the polarization-maintaining fiber, denoted as , where and represent the optical intensities of the two optical pulses respectively, is the imaginary unit, is the phase difference between the two optical pulses; the optical intensity stabilization module is used for the attenuation of two optical pulses; the interference module rotates the polarization directions of the two optical pulses and then couples them, so that the optical pulse transmitted along the fast axis of the polarization-maintaining optical fiber interferes with the optical pulse transmitted along the slow axis of the polarization-maintaining optical fiber; the detection module converts the optical signal obtained after interference into an analog electrical signal; the analog-to-digital conversion module converts the analog electrical signal into a digital electrical signal; the data post-processing module processes the original data; wherein, the pulsed laser module includes a first pulsed laser and a second pulsed laser, the optical intensity stabilization module includes a first optical attenuator and a second optical attenuator, and the interference module includes a polarization-maintaining beam splitter and a polarization beam splitter connected by a polarization-maintaining optical fiber; the first pulsed laser, the first optical attenuator and the polarization-maintaining beam splitter are connected in sequence through a polarization-maintaining optical fiber, and the second pulsed laser, the second optical attenuator and the polarization-maintaining beam splitter are connected in sequence through a polarization-maintaining optical fiber; the first pulsed laser and the second pulsed laser are used to prepare two optical pulses with a high extinction ratio and send the optical pulses to the corresponding optical attenuators; the first optical attenuator and the second optical attenuator attenuate the received optical pulses, and the attenuated optical pulses are sent to the polarization-maintaining beam splitter; the polarization-maintaining beam splitter is a polarization-maintaining input / output beam splitter, which is used to couple two optical pulses into a polarization-maintaining optical fiber; the polarization beam splitter is used to rotate the polarization directions of the two optical pulses and then achieve interference.

2. The quantum random number generation system based on polarization of laser phase fluctuations according to claim 1, characterized in that, the two optical pulses prepared by the pulsed laser module are optical pulses with a high extinction ratio. The duty cycles and frequencies of the two optical pulses are the same, and the optical frequency error between the two optical pulses is within the GHz order of magnitude. The duty cycles of the two optical pulses prepared are both 50%. The optical intensity stabilization module is used for the attenuation of the two optical pulses until the optical intensity difference between the two attenuated optical pulses is within 5%.

3. The quantum random number generation system based on polarization of laser phase fluctuations according to claim 1, characterized in that, The polarization beam splitter is a 45° polarization beam splitter, and the polarization directions of the two optical pulses are rotated by 45°. The 45° rotation matrix is expressed as: .

4. The quantum random number generation system based on polarization of laser phase fluctuations according to claim 1, characterized in that, the detection module includes a first photodetector, the first photodetector is connected to the polarization beam splitter, and the optical signal obtained after the polarization beam splitter realizes interference is expressed as: ； the first photodetector is used to convert the optical signal obtained after interference into an analog electrical signal, and the intensity of the converted analog electrical signal is expressed as: ； Among them, represents the electrical noise of the first photodetector, is the conversion ratio of the first photodetector; the analog-to-digital conversion module is an analog-to-digital converter; the data post-processing module is a computer.

5. The quantum random number generation system based on polarization of laser phase fluctuations according to claim 1, characterized in that, The detection module includes a second photodetector, a third photodetector and a differential amplifier. The second photodetector is connected to the polarization beam splitter and the differential amplifier. The third photodetector is connected to the polarization beam splitter and the differential amplifier. The optical signal obtained after the polarization beam splitter realizes interference and is expressed as: ； The second photodetector and the third photodetector are used to convert the optical signal obtained after interference into an analog electrical signal. The intensity of the converted analog electrical signal is expressed as: ， ； Among them, , respectively represent the electrical noises of the second photodetector and the third photodetector, is the conversion ratio of the second photodetector and the third photodetector; The analog electrical signals are subtracted, and the difference is expressed as: ； Among them, represents the difference in electrical noise between the second photodetector and the third photodetector; The analog-to-digital conversion module is an analog-to-digital converter; The data post-processing module is a computer.

6. A quantum random number generation system based on polarization laser phase fluctuation according to claim 1, characterized in that the pulsed laser module further includes a first temperature control device and a second temperature control device. The first temperature control device is connected to the first pulsed laser, and the first temperature control device is used to adjust the center frequency of the first pulsed laser. The second temperature control device is connected to the second pulsed laser, and the second temperature control device is used to adjust the center frequency of the second pulsed laser.

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