A method and apparatus for monolithically integrated continuous-variable quantum key distribution and quantum random number generation

Abstract

This invention discloses a method and apparatus for monolithically integrated continuous variable quantum key distribution and quantum random number generation. The invention obtains quantum random numbers at the transmitting end through a modulation variance monitoring process and at the receiving end through a shot noise monitoring process. This efficiently achieves integrated quantum key distribution and random number generation functions at both the transmitting and receiving ends, ensuring the security and integration of the CV-QKD chip system.

Description

Technical Field

[0001] This invention belongs to the field of continuous variable quantum secure communication, and particularly relates to a method and apparatus for monolithically integrated continuous variable quantum key distribution and quantum random number generation. Background Technology

[0002] Quantum key distribution (QKD) technology, based on the fundamental principles of quantum mechanics, possesses provable information-theoretic security, effectively resisting quantum computing attacks and showing broad application prospects. QKD technology is mainly divided into two categories: discrete variable and continuous variable. Among them, continuous variable quantum key distribution (CV-QKD) uses the canonical components of the quantum optical field as the carrier of key information. Its devices are compatible with classical coherent optical communication, and it achieves high key generation rates under short-to-medium distance transmission conditions, making it highly suitable for quantum metropolitan area networks and access networks.

[0003] High-performance, highly integrated, and low-cost CV-QKD systems are essential prerequisites for the networking and large-scale application of CV-QKD. Due to the advantages of photonic chip technology in terms of power consumption, bandwidth, speed, and size, manufacturing high-performance, highly integrated, and low-cost CV-QKD systems based on photonic chip technology has become a significant development trend.

[0004] In CV-QKD systems, both the transmitter Alice and the receiver Bob need to use secure and provable true random number sources to ensure the security of quantum key distribution. Among the publicly reported CV-QKD system-on-a-chip solutions, one approach uses pseudo-random numbers or offline acquisition methods, which introduces security vulnerabilities. Another approach uses an external quantum random number generator (QRNG), but this is bulky, has low integration density, and is costly. Therefore, to achieve high integration and large-scale application of CV-QKD while ensuring its security, monolithic integration of CV-QKD and QRNG is necessary. Currently, there is a lack of relevant achievements or solutions in this area. Summary of the Invention

[0005] The purpose of this invention is to address the problem of balancing security and integration in existing CV-QKD chip systems by proposing a method and apparatus for monolithically integrating continuous variable quantum key distribution and quantum random number generation. Quantum random numbers are obtained at the transmitting end through a modulation variance monitoring process, and at the receiving end through a shot noise monitoring process. This efficiently integrates the quantum key distribution and random number generation functions at both the transmitting and receiving ends, ensuring both the security and integration of the CV-QKD chip system.

[0006] On the one hand, the objective of this invention is achieved through the following technical solution:

[0007] A monolithically integrated continuous variable quantum key distribution and quantum random number generation device, comprising: a transmitter and a receiver, wherein the transmitter is connected to the receiver via an optical fiber transmission channel;

[0008] The sending end includes:

[0009] Light source generation module 1 is used to generate optical signals at the transmitting end;

[0010] Coupling module 1 is used to couple the optical signal generated by light source generation module 1 to beam splitting module 1;

[0011] The beam splitting module 1 is used to split the input optical signal into two paths, one of which is output to the detection module 1 and the other is output to the modulation module;

[0012] The modulation module modulates the received optical signal based on the modulation signal generated by the receiving drive module, and outputs the modulated optical signal to the adjustable optical attenuation module.

[0013] The adjustable optical attenuation module attenuates the modulated optical signal based on the electrical signal received from the post-processing module 1, and outputs the attenuated optical signal to the beam splitter 2.

[0014] The beam splitter 2 is used to split the attenuated optical signal into two paths. One path is output to the channel through the coupler 2, and the other path is output to the detection module 1 as a feedback signal for modulation variance detection and quantum random number generation at the transmitting end.

[0015] The detection module 1 is used to detect and filter the received feedback signal to obtain an analog signal and transmit it to the analog-to-digital conversion module 1;

[0016] Analog-to-digital conversion module 1 is used to convert the received analog signal into a digital signal and transmit it to post-processing module 1;

[0017] Post-processing module 1 is used for modulation variance monitoring and random number generation, as well as parameter estimation, bit error correction and security enhancement;

[0018] The driving module 1 generates a driving voltage based on the modulation driving signal generated by the receiving post-processing module 1, which is used to drive the modulation module.

[0019] Coupling module 2 couples the quantum signal light to the optical fiber transmission channel;

[0020] The receiving end includes:

[0021] Coupling module 3 receives the signal input from the optical fiber transmission channel and couples the channel quantum signal to the optical switch module;

[0022] The optical switch module is used to turn the input signal light off or on to achieve shot noise calibration and receiver quantum random number generation.

[0023] The beam splitter module 3 is used to split the received signal light into two paths, one of which is output to the mixer module 1 and the other is output to the mixer module 2.

[0024] Light source generation module 2 is used to generate the local oscillator light signal at the receiving end;

[0025] Coupling module 4 couples the local oscillator light generated by light source generation module 2 to beam splitting module 4;

[0026] The beam splitting module 4 is used to split the local oscillator light source at the receiving end into two paths, one of which is output to the mixing module 1 and the other is output to the mixing module 2.

[0027] Mixer module 1 is used for coherent mixing of the X component of the CV-QKD system;

[0028] Mixer module 2 is used for coherent mixing of the P component in the CV-QKD system;

[0029] Detection module 2 is used to receive the output signals of mixing module 1 and mixing module 2 to achieve coherent detection;

[0030] The analog-to-digital conversion module 2 converts the analog signal output from the detection module 2 into a digital signal and transmits it to the post-processing module 2.

[0031] Post-processing module 2 completes shot noise monitoring, random number generation, parameter estimation, bit error correction, and security enhancement;

[0032] The driving module 2 receives the optical switch driving signal generated by the post-processing module 2 and generates a driving voltage to drive the optical switch module.

[0033] According to a preferred embodiment, the modulation module employs a modulation method including IQ modulation, amplitude modulation, or phase modulation.

[0034] According to a preferred embodiment, the light source generating module 1 and the light source generating module 2 can be input to the chip externally via a coupling module, or they can be integrated inside the chip in a heterogeneous manner.

[0035] According to a preferred embodiment, the detection module 1 and the detection module 2 employ zero-difference detection or heterodyne detection methods to achieve detection.

[0036] According to a preferred embodiment, the optical switch module employs an MZI structure intensity modulator composed of an electro-optic phase shifter.

[0037] According to a preferred embodiment, the mixing module 1 and the mixing module 2 are either 90-degree mixing modules or 180-degree mixing modules.

[0038] On the other hand, the present invention also discloses:

[0039] A method for monolithically integrated continuous variable quantum key distribution and quantum random number generation, employing the aforementioned apparatus, comprises: a random number extraction method of the transmitting end post-processing module 1, a random number extraction method of the receiving end post-processing module 2, and a quantum key distribution method.

[0040] The random number extraction method of the post-processing module 1 at the sending end is as follows:

[0041] Step A1: Electrical noise calibration. By disconnecting the electrical signal of the light source generation module 1, the optical signal input is made zero. The detection module 1 collects the electrical noise and calculates the electrical noise variance Var_ele_1.

[0042] Step A2: Data sampling. The light source generation module 1 generates a light signal normally. The drive module 1 controls the output amplitude of the modulated light signal to be zero, and the attenuation value of the adjustable light attenuation module is adjusted to the maximum value. At this time, the detection module 1 collects the sum of shot noise and electrical noise. Based on the ADC, the detector output signal is discretized and sampled, and its variance Var_snt_1 is obtained.

[0043] Step A3: Entropy assessment, assessing the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) is the minimum entropy of the quantum components in the sampled signal or the conditional minimum entropy of the sampling sequence under known electrical noise conditions;

[0044] Step A4: Randomness extraction, based on the entropy evaluation results of step A3, and randomness extraction is implemented based on data post-processing module 1.

[0045] According to a preferred embodiment, the random number extraction method of the post-processing module 2 at the receiving end is to multiplex the random number sequence from the shot noise monitoring stage, including:

[0046] Step B1: Electrical noise calibration. The electrical signal of the light source generation module 2 is disconnected to make the optical signal input zero. At the same time, the optical signal input of the coupling module 3 is disconnected. Then, the detection module 2 collects the electrical noise and calibrates the electrical noise variance Var_ele_2.

[0047] Step B2: Data sampling. The drive module 2 controls the optical switch module to cut off the quantum signal light input. At this time, the detection module 2 collects the sum of shot noise and electrical noise. Based on the ADC, the detector output signal is discretized and sampled, and its variance Var_snt_2 is obtained.

[0048] Step B3: Entropy assessment, assessing the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) is the minimum entropy of the quantum components in the sampled signal or the conditional minimum entropy of the sampling sequence under known electrical noise conditions;

[0049] Step B4: Randomness extraction, based on the entropy evaluation results of step B3, and randomness extraction is implemented based on data post-processing module 2.

[0050] According to a preferred embodiment, in steps A4 and B4, the randomness extraction method includes the Toplitz matrix method, the hash function method, and the truncation XOR method.

[0051] According to a preferred embodiment, a method for quantum key distribution using a monolithically integrated continuous-variable quantum key distribution and quantum random number generation device is as follows:

[0052] Step C1: Electrical noise acquisition. Before the CV-QKD system starts working, the light source generation module 1 and the light source generation module 2 ensure no light signal input by inputting zero. The detection module 1 and the detection module 2 respectively acquire the electrical noise variance of the transmitting end and the receiving end detection module.

[0053] Step C2: Shot noise calibration. Light source generation module 1 and light source generation module 2 generate optical signals, and the CV-QKD system starts.

[0054] At the transmitting end, by adjusting the attenuation of the modulation module and the attenuation of the adjustable optical attenuator module to the maximum attenuation value, the detection module 1 discretizes the detector output signal based on the ADC.

[0055] At the receiving end, when the quantum signal detected at the transmitting end is 0, the optical switch module is immediately disconnected, and the detection module 2 performs discretization sampling of the detector output signal based on the ADC.

[0056] Step C3: Random number extraction: The transmitting end and the receiving end extract quantum random numbers from the sequence acquired by the ADC through post-processing module 1 and post-processing module 2 respectively and store them in the memory;

[0057] Step C4: Quantum signal modulation. The transmitting end generates a corresponding modulation signal using the random numbers stored at the transmitting end, thereby realizing quantum signal modulation at the transmitting end.

[0058] Step C5: Key distribution, where the transmitting end generates and modulates quantum signals, and the receiving end detects quantum signals;

[0059] Step C6: Data post-processing. The sending and receiving ends perform real-time data post-processing through parameter estimation, quantization negotiation, key error correction, and security enhancement. In this stage, the receiving end uses the quantum random numbers stored at the receiving end to perform random basis selection.

[0060] The aforementioned main solution of the present invention and its various further alternative solutions can be freely combined to form multiple solutions, all of which are solutions that can be adopted and are claimed by the present invention. Those skilled in the art, after understanding the solution of the present invention, will realize that there are many combinations based on existing technology and common knowledge, all of which are technical solutions to be protected by the present invention, and will not be exhaustively listed here.

[0061] The beneficial effects of this invention are:

[0062] This invention achieves monolithic integration of CV-QKD and QRNG, solving the problem of balancing security and integration in existing CV-QKD chip systems. Simultaneously, the quantum random number generation and system shot noise calibration processes are multiplexed, saving ADC and detector resources, improving system hardware utilization, and reducing system cost. Attached Figure Description

[0063] Figure 1 This is a schematic diagram illustrating the structural principle of the monolithically integrated CV-QKD and QRNG device of the present invention. Detailed Implementation

[0064] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0065] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0066] In the description of this invention, it should be noted that the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. It should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0067] Furthermore, it should be noted that, unless otherwise specified, the structures, connections, positions, power sources, etc. involved in this invention are all things that a person skilled in the art can know without creative effort based on the prior art.

[0068] Example 1

[0069] refer to Figure 1 As shown in the figure, a monolithically integrated continuous variable quantum key distribution and quantum random number generation device is illustrated, comprising a transmitter and a receiver.

[0070] The sending end includes:

[0071] Light source generation module 1 is used to generate optical signals at the transmitting end.

[0072] The coupling module 1 couples the optical signal generated by the light source generation module 1 to the beam splitting module 1 of the transmitting optical chip.

[0073] The beam splitter module 1 splits the input optical signal into two paths, one of which is output to the detector module 1 and the other is output to the modulation module.

[0074] The driving module 1 receives the modulation driving signal generated by the post-processing module 1 and generates a driving voltage to drive the modulation module.

[0075] The modulation module receives the modulation signal generated by the driver module, modulates the optical signal, and outputs the modulated optical signal to the adjustable optical attenuation module.

[0076] The adjustable optical attenuation module receives the electrical signal from the digital-to-analog converter module, attenuates the modulated optical signal, and outputs the attenuated optical signal to the beam splitter module 2.

[0077] The beam splitter module 2 is used to split the attenuated optical signal into two paths. One path is output to the channel through the coupler 2, and the other path is output to the detection module 1 as a feedback signal for modulation variance detection and quantum random number generation at the transmitting end.

[0078] Coupling module 2 couples the quantum signal light to the optical fiber transmission channel.

[0079] The detection module 1 detects and filters the received feedback signal to obtain an analog signal, which is then transmitted to the analog-to-digital conversion module 1.

[0080] The analog-to-digital conversion module 1 converts the received analog signal into a digital signal and transmits it to the post-processing module 1.

[0081] Post-processing module 1 is used for modulation variance monitoring and random number generation, as well as parameter estimation, bit error correction and security enhancement.

[0082] The receiving end includes:

[0083] Coupling module 3 couples the channel quantum signal to the optical switch module of the receiver optical chip.

[0084] Light source generation module 2 is used to generate the local oscillator light signal at the receiving end.

[0085] The coupling module 4 couples the local oscillator light generated by the light source generation module 2 to the beam splitting module 4 of the transmitting optical chip.

[0086] The driving module 2 receives the optical switch driving signal generated by the post-processing module 2 and generates a driving voltage to drive the optical switch module.

[0087] Optical switch module: used to turn the input signal light off or on, to achieve shot noise calibration and quantum random number generation at the receiver.

[0088] The beam splitter module 3 is used to split the signal light into two paths, one of which is output to the mixer module 1 and the other is output to the mixer module 2.

[0089] The beam splitter module 4 is used to split the local oscillator light source at the receiving end into two paths, one of which is output to the mixer module 1 and the other is output to the mixer module 2.

[0090] Mixer module 1 is used for coherent mixing of the X (or P) component of the CV-QKD system.

[0091] Mixer module 2 is used for coherent mixing of the P (or X) components of the CV-QKD system.

[0092] Detection module 2 is used to receive the output signals of mixing modules 1 and 2 to achieve coherent detection.

[0093] The analog-to-digital conversion module 2 converts the received analog signal into a digital signal and transmits it to the post-processing module 2.

[0094] Post-processing module 2 completes shot noise monitoring, random number generation, parameter estimation, error correction, and security enhancement.

[0095] Furthermore, the modulation module can employ any modulation method such as IQ modulation, amplitude modulation, or phase modulation.

[0096] Furthermore, the adjustable light attenuation module can employ an MZI structure intensity modulator composed of a thermal phase shifter to achieve a high-precision attenuation design.

[0097] Furthermore, the beam splitting module 1, beam splitting module 2, beam splitting module 3 and beam splitting module 4 can be beam splitters or directional couplers with MMI structure.

[0098] Furthermore, the detection module 1 and the detection module 2 employ zero-difference detection or heterodyne detection.

[0099] Furthermore, the analog-to-digital conversion module 1 and the analog-to-digital conversion module 2 are implemented using ADC chips.

[0100] Furthermore, the optical switch module employs an MZI structure intensity modulator composed of an electro-optic phase shifter, which enables high-speed switching.

[0101] Furthermore, the mixing module 1 and mixing module 2 are either 90-degree mixing modules or 180-degree mixing modules.

[0102] Furthermore, the internal modules of the chip are connected using optical waveguides.

[0103] Furthermore, the light source generating module 1 and the light source generating module 2 can be input to the chip from outside the chip via a coupling module, or they can be integrated inside the chip via heterogeneity or other means.

[0104] Furthermore, the chip can be based on silicon, indium phosphide, indium gallium arsenide, silicon nitride, and other platforms.

[0105] Example 2

[0106] Based on Embodiment 1, this embodiment discloses a method for monolithically integrated continuous variable quantum key distribution and quantum random number generation, using the aforementioned apparatus. The method for monolithically integrated continuous variable quantum key distribution and quantum random number generation includes: a random number extraction method of the transmitting end post-processing module 1, a random number extraction method of the receiving end post-processing module 2, and a quantum key distribution method.

[0107] The random number extraction method of the post-processing module 1 at the sending end is as follows:

[0108] Step A1: Electrical noise calibration - By disconnecting the electrical signal of the light source generation module 1, the optical signal input is made zero. The detection module 1 collects the electrical noise and calculates the electrical noise variance Var_ele_1.

[0109] Step A2: Data Sampling - The light source generation module 1 generates a light signal normally, the drive module 1 controls the output amplitude of the modulated light signal to be zero, and the attenuation value of the adjustable light attenuation module is adjusted to the maximum value. At this time, the detection module 1 collects the sum of shot noise and electrical noise, discretizes the detector output signal based on the ADC, and calculates its variance Var_snt_1.

[0110] Step A3: Entropy assessment – ​​assess the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) can be the minimum entropy of the quantum components in the sampled signal or the conditional minimum entropy of the sampling sequence under known electrical noise conditions, etc.

[0111] Step A4: Randomness Extraction – Based on the entropy evaluation results, randomness extraction is performed using data post-processing module 1. Randomness extraction methods include, but are not limited to, the Toplitz matrix method, hash function method, and truncation XOR method.

[0112] Furthermore, the random number extraction method of the receiving end post-processing module 2 is to multiplex the random number sequence from the shot noise monitoring stage, and the specific steps are as follows:

[0113] Step B1: Electrical noise calibration—By disconnecting the electrical signal of the light source generation module 2, the optical signal input is made zero. At the same time, the optical signal input of the coupling module 3 is disconnected. Then, the detection module 2 collects the electrical noise and calibrates the electrical noise variance Var_ele_2.

[0114] Step B2: Data Sampling - The drive module 2 controls the optical switch module to cut off the quantum signal light input. At this time, the detection module 2 collects the sum of shot noise and electrical noise, discretizes the detector output signal based on the ADC, and calculates its variance Var_snt_2.

[0115] Step B3: Entropy assessment – ​​assess the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) can be the minimum entropy of the quantum components in the sampled signal or the conditional minimum entropy of the sampling sequence under known electrical noise conditions, etc.

[0116] Step B4: Randomness Extraction – Based on the entropy evaluation results, randomness extraction is performed using data post-processing module 2. Randomness extraction methods include, but are not limited to, the Toplitz matrix method, hash function method, and truncation XOR method.

[0117] Furthermore, the quantum key distribution method is as follows:

[0118] Step C1: Electrical noise acquisition: Before the CV-QKD system starts working, the light source generation modules at the transmitting and receiving ends ensure that there is no light signal input to the chip system by inputting zero. Detection module 1 and detection module 2 respectively acquire the electrical noise variance of the transmitting and receiving detection modules.

[0119] Step C2: Shot Noise Calibration: The light source generation modules at the transmitting and receiving ends generate optical signals, and the system starts. At the transmitting end, by adjusting the attenuation of the modulation module and the attenuation of the adjustable optical attenuator module to the maximum attenuation value, the detection module 1 discretizes the detector output signal based on the ADC; at the receiving end, when the quantum signal detected at the transmitting end is 0, the light switch is immediately turned off, and the detection module 2 discretizes the detector output signal based on the ADC.

[0120] Step C3: Random number extraction: Based on the sequence acquired by the ADC, the transmitting and receiving ends extract quantum random numbers through the post-processing module and store them in the memory.

[0121] Step C4: Quantum signal modulation: The transmitter generates a corresponding modulation signal using the random numbers stored at the transmitter, thus realizing quantum signal modulation at the transmitter.

[0122] Step C5: Key distribution: The transmitting end realizes quantum signal generation and modulation, and the receiving end realizes quantum signal detection.

[0123] Step C6: Data Post-processing: The sender and receiver perform real-time data post-processing through parameter estimation, quantization negotiation, key error correction, and security enhancement. In this stage, the receiver's data post-processing utilizes quantum random numbers stored at the receiver for random basis selection.

[0124] This invention achieves monolithic integration of CV-QKD and QRNG, solving the problem of balancing security and integration in existing CV-QKD chip systems. Simultaneously, the quantum random number generation and system shot noise calibration processes are multiplexed, saving ADC and detector resources, improving system hardware utilization, and reducing system cost.

[0125] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A monolithically integrated continuous-variable quantum key distribution and quantum random number generation device, characterized in that, The monolithically integrated continuous variable quantum key distribution and quantum random number generation device includes: a transmitter and a receiver, wherein the transmitter is connected to the receiver via an optical fiber transmission channel; The sending end includes: Light source generation module 1 is used to generate optical signals at the transmitting end; Coupling module 1 is used to couple the optical signal generated by light source generation module 1 to beam splitting module 1; The beam splitting module 1 is used to split the input optical signal into two paths, one of which is output to the detection module 1 and the other is output to the modulation module; The modulation module modulates the received optical signal based on the modulation signal generated by the receiving drive module, and outputs the modulated optical signal to the adjustable optical attenuation module. The adjustable optical attenuation module attenuates the modulated optical signal based on the electrical signal received from the post-processing module 1, and outputs the attenuated optical signal to the beam splitter 2. The beam splitter 2 is used to split the attenuated optical signal into two paths. One path is output to the channel through the coupler 2, and the other path is output to the detection module 1 as a feedback signal for modulation variance detection and quantum random number generation at the transmitting end. The detection module 1 is used to detect and filter the received feedback signal to obtain an analog signal and transmit it to the analog-to-digital conversion module 1; Analog-to-digital conversion module 1 is used to convert the received analog signal into a digital signal and transmit it to post-processing module 1; Post-processing module 1 is used for modulation variance monitoring and random number generation, as well as parameter estimation, bit error correction and security enhancement; The driving module 1 generates a driving voltage based on the modulation driving signal generated by the receiving post-processing module 1, which is used to drive the modulation module. Coupling module 2 couples the quantum signal light to the optical fiber transmission channel; The receiving end includes: Coupling module 3 receives the signal input from the optical fiber transmission channel and couples the channel quantum signal to the optical switch module; The optical switch module is used to turn the input signal light off or on to achieve shot noise calibration and receiver quantum random number generation. The beam splitter module 3 is used to split the received signal light into two paths, one of which is output to the mixer module 1 and the other is output to the mixer module 2. Light source generation module 2 is used to generate the local oscillator light signal at the receiving end; Coupling module 4 couples the local oscillator light generated by light source generation module 2 to beam splitting module 4; The beam splitting module 4 is used to split the local oscillator light source at the receiving end into two paths, one of which is output to the mixing module 1 and the other is output to the mixing module 2. Mixer module 1 is used for coherent mixing of the X component of the CV-QKD system; Mixer module 2 is used for coherent mixing of the P component in the CV-QKD system; Detection module 2 is used to receive the output signals of mixing module 1 and mixing module 2 to achieve coherent detection; The analog-to-digital conversion module 2 converts the analog signal output from the detection module 2 into a digital signal and transmits it to the post-processing module 2. Post-processing module 2 completes shot noise monitoring, random number generation, parameter estimation, bit error correction, and security enhancement; The driving module 2 receives the optical switch driving signal generated by the post-processing module 2 and generates a driving voltage to drive the optical switch module.

2. The monolithically integrated continuous-variable quantum key distribution and quantum random number generation device as described in claim 1, characterized in that, The modulation method used by the modulation module includes: IQ modulation, amplitude modulation, or phase modulation.

3. The monolithically integrated continuous-variable quantum key distribution and quantum random number generation device as described in claim 1, characterized in that, The light source generating module 1 and the light source generating module 2 are either input to the chip externally via a coupling module, or integrated inside the chip via a heterogeneous or heterogeneous approach.

4. The monolithically integrated continuous-variable quantum key distribution and quantum random number generation device as described in claim 1, characterized in that, The detection module 1 and detection module 2 employ either zero-difference detection or heterodyne detection methods to achieve detection.

5. The monolithically integrated continuous-variable quantum key distribution and quantum random number generation device as described in claim 1, characterized in that, The optical switch module uses an MZI structure intensity modulator composed of an electro-optic phase shifter.

6. The monolithically integrated continuous-variable quantum key distribution and quantum random number generation device as described in claim 1, characterized in that, The mixing module 1 and mixing module 2 are either 90-degree mixing modules or 180-degree mixing modules.

7. A method for monolithically integrated continuous-variable quantum key distribution and quantum random number generation, characterized in that, Using the apparatus as described in any one of claims 1 to 5, the method for monolithically integrated continuous variable quantum key distribution and quantum random number generation includes: a random number extraction method of the post-processing module 1 at the transmitting end, a random number extraction method of the post-processing module 2 at the receiving end, and a quantum key distribution method. The random number extraction method of the post-processing module 1 at the sending end is as follows: Step A1: Electrical noise calibration. By disconnecting the light source and generating the electrical signal of module 1, the optical signal input is made zero. Detection module 1 collects the electrical noise and calculates the electrical noise variance Var ele 1. Step A2: Data sampling. The light source generation module 1 generates a light signal normally. The drive module 1 controls the output amplitude of the modulated light signal to be zero, and the attenuation value of the adjustable light attenuation module is adjusted to the maximum value. At this time, the detection module 1 collects the sum of shot noise and electrical noise. Based on the ADC, the detector output signal is discretized and sampled, and its variance Var_snt_1 is obtained. Step A3: Entropy assessment, assessing the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) is the minimum entropy of the quantum components in the sampled signal or the conditional minimum entropy of the sampling sequence under known electrical noise conditions; Step A4: Randomness extraction, based on the entropy evaluation results of step A3, and randomness extraction is implemented based on data post-processing module 1.

8. The method for monolithically integrated continuous-variable quantum key distribution and quantum random number generation as described in claim 7, characterized in that, The random number extraction method of the post-processing module 2 at the receiving end is to multiplex the random number sequence from the shot noise monitoring stage, including: Step B1: Electrical noise calibration. The electrical signal of the light source generation module 2 is disconnected to make the optical signal input zero. At the same time, the optical signal input of the coupling module 3 is disconnected. Then, the detection module 2 collects the electrical noise and calibrates the electrical noise variance Var_ele_2. Step B2: Data sampling. The drive module 2 controls the optical switch module to cut off the quantum signal light input. At this time, the detection module 2 collects the sum of shot noise and electrical noise. Based on the ADC, the detector output signal is discretized and sampled, and its variance Var_snt_2 is obtained. Step B3: Entropy assessment, assessing the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) is the minimum entropy of the quantum components in the sampled signal or the conditional minimum entropy of the sampling sequence under known electrical noise conditions; Step B4: Randomness extraction, based on the entropy evaluation results of step B3, and randomness extraction is implemented based on data post-processing module 2.

9. The method for monolithically integrated continuous-variable quantum key distribution and quantum random number generation as described in claim 8, characterized in that, In steps A4 and B4, the randomness extraction methods include the Toplitz matrix method, the hash function method, and the truncation XOR method.

10. The method for monolithically integrated continuous-variable quantum key distribution and quantum random number generation as described in claim 7, characterized in that, The method for quantum key distribution using a device that integrates continuous-variable quantum key distribution and quantum random number generation on a single chip is as follows: Step C1: Electrical noise acquisition. Before the CV-QKD system starts working, the light source generation module 1 and the light source generation module 2 ensure no light signal input by inputting zero. The detection module 1 and the detection module 2 respectively acquire the electrical noise variance of the transmitting end and the receiving end detection module. Step C2: Shot noise calibration. Light source generation module 1 and light source generation module 2 generate optical signals, and the CV-QKD system starts. At the transmitting end, by adjusting the attenuation of the modulation module and the attenuation of the adjustable optical attenuator module to the maximum attenuation value, the detection module 1 discretizes the detector output signal based on the ADC. At the receiving end, when the quantum signal detected at the transmitting end is 0, the optical switch module is immediately disconnected, and the detection module 2 performs discretization sampling of the detector output signal based on the ADC. Step C3: Random number extraction: The transmitting end and the receiving end extract quantum random numbers from the sequence acquired by the ADC through post-processing module 1 and post-processing module 2 respectively and store them in the memory; Step C4: Quantum signal modulation. The transmitting end generates a corresponding modulation signal using the random numbers stored at the transmitting end, thereby realizing quantum signal modulation at the transmitting end. Step C5: Key distribution, where the transmitting end generates and modulates quantum signals, and the receiving end detects quantum signals; Step C6: Data post-processing. The sending and receiving ends perform real-time data post-processing through parameter estimation, quantization negotiation, key error correction, and security enhancement. In this stage, the receiving end uses the quantum random numbers stored at the receiving end to perform random basis selection.

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