Monolithic integration continuous variable quantum key distribution and quantum random number generation method and device

Abstract

The invention discloses a monolithic integration continuous variable quantum key distribution and quantum random number generation method and device, and the method comprises the steps: obtaining a quantum random number at a transmitting end through a modulation variance monitoring process, and obtaining the quantum random number at a receiving end through a shot noise monitoring process; therefore, the integration of quantum key distribution and random number generation functions of the sending end and the receiving end is efficiently realized, and the safety and the integration degree of a CV-QKD chip system are ensured.

Description

Technical Field

[0001] The present invention belongs to the field of continuous variable quantum secure communication, and in particular relates to a method and device for monolithic integrated continuous variable quantum key distribution and quantum random number generation. Background Art

[0002] Quantum Key Distribution (QKD) technology is based on the basic principles of quantum mechanics, has provable information-theoretic security, can effectively resist quantum computing decryption attacks, and has broad application prospects. QKD technology is mainly divided into two major technical systems: discrete variables and continuous variables. Among them, continuous variable quantum key distribution (CV-QKD) uses the canonical component of the quantum light field as the carrier of key information. The device is common to classical coherent optical communications, has a high coding rate under medium and short distance transmission conditions, and is very suitable for quantum metropolitan area networks and access network applications.

[0003] High-performance, highly integrated, and low-cost CV-QKD systems are an important prerequisite for the networking and large-scale application of CV-QKD. As photonic chip technology has advantages in energy consumption, bandwidth, speed, size, etc., manufacturing high-performance, highly integrated, and low-cost CV-QKD systems based on photonic chip technology has become an important development trend.

[0004] In the CV-QKD system, both the sender Alice and the receiver Bob need to use a secure and provable true random number source to ensure the security of quantum key distribution. In the existing publicly reported CV-QKD system chip achievements, one way of obtaining random numbers is to use pseudo-random numbers or to obtain them offline, which poses a security risk to the system; another way is to use an external quantum random number generator (Quantum Random Number Generator, QRNG), but it is large in size, low in integration, and high in cost. Therefore, in order to achieve high integration and large-scale application of CV-QKD and ensure its security, it is necessary to realize the monolithic integration of CV-QKD and QRNG. At present, there is no relevant achievement or solution. Summary of the invention

[0005] The purpose of the present invention is to propose a method and device for monolithic integrated continuous variable quantum key distribution and quantum random number generation in view of the problem that it is difficult to balance the security and integration of the existing CV-QKD chip system, wherein quantum random numbers are obtained through a modulation variance monitoring process at the transmitting end and through a shot noise monitoring process at the receiving end, thereby efficiently realizing the integrated integration of quantum key distribution and random number generation functions at the transmitting end and the receiving end, and ensuring the security and integration of the CV-QKD chip system.

[0006] On the one hand, the purpose of the present invention is achieved by the following technical solutions:

[0007] A monolithic integrated continuous variable quantum key distribution and quantum random number generation device, the monolithic integrated continuous variable quantum key distribution and quantum random number generation device comprising: a transmitting end and a receiving end, the transmitting end is connected to the receiving end via an optical fiber transmission channel;

[0008] Wherein, the sending end includes:

[0009] Light source generating module 1, used for generating light signals at the transmitting end;

[0010] The coupling module 1 is used to couple the optical signal generated by the light source generating module 1 to the light splitting module 1;

[0011] The optical splitter 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] A modulation module, which modulates the received optical signal based on the modulation signal generated by the receiving driving 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 optical splitting module 2;

[0014] The optical splitter module 2 is used to split the attenuated optical signal into two paths, one of which is output to the channel through the coupler 2, and the other 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, obtain an analog signal and transmit it to the analog-to-digital conversion module 1;

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

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

[0018] The driving module 1 generates a driving voltage based on the modulated driving signal generated by the receiving post-processing module 1, so as to drive the modulation module;

[0019] Coupling module 2, coupling the quantum signal light into the optical fiber transmission channel;

[0020] The receiving end comprises:

[0021] The 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] Optical switch module, used to turn off or turn on the input signal light to achieve shot noise calibration and quantum random number generation at the receiving end;

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

[0024] Light source generating module 2, used for generating local oscillator light signal at the receiving end;

[0025] The coupling module 4 couples the local oscillator light generated by the light source generating module 2 to the light splitting module 4;

[0026] The optical 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 mixing module 1 and the other is output to the mixing module 2;

[0027] Mixing module 1, used for coherent mixing of X component of CV-QKD system;

[0028] Mixing module 2, used for coherent mixing of the P component of the CV-QKD system;

[0029] Detection module 2, used for receiving the output signals of mixing module 1 and mixing module 2 to realize coherent detection;

[0030] The analog-to-digital conversion module 2 converts the analog signal output by 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, error correction and confidentiality enhancement;

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

[0033] According to a preferred implementation, the modulation mode adopted by the modulation module includes: 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 into the chip through a coupling module outside the chip, or 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 implement detection by homodyne detection or heterodyne detection.

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

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

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

[0039] A method for monolithic integrated continuous variable quantum key distribution and quantum random number generation, using the above-mentioned device, the method for monolithic integrated continuous variable quantum key distribution and quantum random number generation comprises: a random number extraction method of a post-processing module 1 at a transmitting end, a random number extraction method of a post-processing module 2 at a receiving end, and a quantum key distribution method;

[0040] Among them, the random number extraction method of the sending end post-processing module 1 is:

[0041] Step A1: electrical noise calibration, by disconnecting the electrical signal of the light source generating module 1, making the optical signal input zero, the detection module 1 collects electrical noise, and obtains the electrical noise variance Var_ele_1;

[0042] Step A2: data sampling, the light source generating module 1 generates a light signal normally, the driving module 1 controls the modulated light signal output amplitude 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 the shot noise and the electrical noise, and the detector output signal is discretized and sampled based on the ADC, and its variance Var_snt_1 is obtained;

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

[0044] Step A4: randomness extraction, based on the entropy evaluation result of step A3 and based on the data post-processing module 1 to achieve randomness extraction.

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

[0046] Step B1: electrical noise calibration, by disconnecting the electrical signal of the light source generating module 2, making the optical signal input zero, and disconnecting the optical signal input of the coupling module 3, then the detection module 2 collects the electrical noise, and calibrates the electrical noise variance Var_ele_2;

[0047] Step B2: Data sampling, the driving 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, and discretizes and samples the detector output signal based on ADC, and obtains its variance Var_snt_2;

[0048] Step B3: Entropy evaluation, evaluating the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) is the minimum entropy of the quantum component 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 result of step B3 and based on the data post-processing module 2 to achieve randomness extraction.

[0050] According to a preferred embodiment, in step A4 and step B4, the randomness extraction method includes a Toeplitz matrix method, a hash function method, and a truncated XOR method.

[0051] According to a preferred embodiment, the method for performing quantum key distribution by a monolithic integrated continuous variable quantum key distribution and quantum random number generation device is:

[0052] Step C1: electrical noise collection. Before the CV-QKD system works, the light source generation module 1 and the light source generation module 2 input zero to ensure that there is no light signal input. The detection module 1 and the detection module 2 respectively obtain the electrical noise variance of the detection module at the transmitting end and the receiving end;

[0053] Step C2: Shot noise calibration, light source generation module 1 and light source generation module 2 generate light 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 output signal of the detector based on the ADC;

[0055] At the receiving end, when the quantum signal of the sending end is detected to be 0, the optical switch module is immediately disconnected, and the detection module 2 discretizes the output signal of the detector based on the ADC;

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

[0057] Step C4: quantum signal modulation, the sending end generates a corresponding modulation signal through the random number stored in the sending end, thereby realizing quantum signal modulation at the sending end;

[0058] Step C5: key distribution, the sending end realizes quantum signal generation and modulation, and the receiving end realizes quantum signal detection;

[0059] Step C6: Data post-processing. The sender and receiver implement real-time data post-processing through parameter estimation, quantization negotiation, key error correction and confidentiality enhancement. At this stage, the receiver's data post-processing will use the quantum random numbers stored at the receiver for random base selection.

[0060] The aforementioned main scheme of the present invention and its further options can be freely combined to form multiple schemes, all of which are schemes that can be adopted and claimed for protection by the present invention. After understanding the scheme of the present invention, those skilled in the art can understand that there are multiple combinations based on the prior art and common knowledge, all of which are technical schemes to be protected by the present invention, and they are not exhaustively listed here.

[0061] Beneficial effects of the present invention:

[0062] The present invention realizes the monolithic integration of CV-QKD and QRNG, solving the problem that the existing CV-QKD chip system security and integration are difficult to balance. At the same time, the quantum random number generation and the system shot noise calibration process are reused, saving ADC and detector resources, improving the system hardware utilization, and reducing system costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 It is a schematic diagram of the structural principle of the monolithic integrated CV-QKD and QRNG device of the present invention. DETAILED DESCRIPTION

[0064] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[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, further definition and explanation thereof is not required in subsequent drawings.

[0066] In the description of the present invention, it should be noted that, in addition, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0067] In addition, the present invention should be pointed out that, in the present invention, unless the specific structure, connection relationship, positional relationship, power source relationship, etc. are specifically written out, the structure, connection relationship, positional relationship, power source relationship, etc. involved in the present invention are all known by those skilled in the art on the basis of the prior art without creative work.

[0068] Example 1

[0069] refer to Figure 1 As shown, the figure shows a monolithic integrated continuous variable quantum key distribution and quantum random number generation device, including a transmitting end and a receiving end.

[0070] The sending end includes:

[0071] The light source generating module 1 is used for generating the optical signal at the transmitting end.

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

[0073] The optical splitter module 1 splits 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.

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

[0075] The modulation module receives the modulation signal generated by the driving 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 conversion module, attenuates the modulated optical signal, and outputs the attenuated optical signal to the optical splitting module 2.

[0077] The optical splitter module 2 is used to split the attenuated optical signal into two paths, one of which is output to the channel through the coupler 2, and the other 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] The 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, obtains an analog signal and transmits it 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] The post-processing module 1 is used for modulation variance monitoring and random number generation, as well as parameter estimation, error correction and confidentiality enhancement.

[0082] The receiving end includes:

[0083] The coupling module 3 couples the channel quantum signal to the optical switch module of the receiving end optical chip.

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

[0085] The coupling module 4 couples the local oscillation light generated by the light source generating module 2 to the light splitting module 4 of the transmitting end 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 for driving the optical switch module.

[0087] Optical switch module: used to turn off or turn on the input signal light to achieve shot noise calibration and generate quantum random numbers at the receiving end.

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

[0089] The light 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.

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

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

[0092] The detection module 2 is used to receive the output signals of the 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 confidentiality enhancement.

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

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

[0097] Furthermore, the optical splitter module 1, the optical splitter module 2, the optical splitter module 3 and the optical splitter module 4 may adopt an MMI structure beam splitter or a directional coupler.

[0098] Furthermore, the detection module 1 and the detection module 2 adopt homodyne 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 adopts an MZI structure intensity modulator composed of an electro-optical phase shifter, which can achieve high-speed switching.

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

[0102] Furthermore, the connection between the modules inside the chip is achieved by optical waveguide connection.

[0103] Furthermore, the light source generating module 1 and the light source generating module 2 may be input into the chip through a coupling module outside the chip, or may be integrated inside the chip through heterogeneity or heterogeneity.

[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 Example 1, this embodiment discloses a method for monolithic integrated continuous variable quantum key distribution and quantum random number generation, using the aforementioned device. The method for monolithic integrated continuous variable quantum key distribution and quantum random number generation includes: a random number extraction method of a post-processing module 1 at the sending end, a random number extraction method of a post-processing module 2 at the receiving end, and a quantum key distribution method.

[0107] Among them, the random number extraction method of the sending end post-processing module 1 is:

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

[0109] Step A2: Data sampling - the light source generating module 1 generates light signals normally, the driving 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, and discretizes and samples the detector output signal based on the ADC, and calculates its variance Var_snt_1.

[0110] Step A3: Entropy evaluation - evaluate 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 result, randomness extraction is implemented based on the data post-processing module 1. The randomness extraction methods include but are not limited to the Toeplitz matrix method, the hash function method, the truncated XOR method, etc.

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

[0113] Step B1: electrical noise calibration - by disconnecting the electrical signal of the light source generating module 2, the optical signal input is made zero, and the optical signal input of the coupling module 3 is disconnected, and then the detection module 2 collects the electrical noise and calibrates the electrical noise variance Var_ele_2.

[0114] Step B2: Data sampling - the driving 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, and discretizes and samples the detector output signal based on the ADC, and calculates its variance Var_snt_2.

[0115] Step B3: Entropy evaluation - evaluate 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 result, randomness extraction is implemented based on the data post-processing module 2. The randomness extraction methods include but are not limited to the Toeplitz matrix method, the hash function method, the truncated XOR method, etc.

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

[0118] Step C1: Electrical noise collection: Before the CV-QKD system works, the light source generating modules at the transmitting and receiving ends input zero to ensure that there is no optical signal input to the chip system. Detection module 1 and detection module 2 obtain the electrical noise variance of the detection modules at the transmitting and receiving ends respectively.

[0119] Step C2: Shot noise calibration: The light source generation modules at the transmitting end and the receiving end 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 output signal of the detector based on the ADC; at the receiving end, when the quantum signal of the transmitting end is detected to be 0, the optical switch is immediately disconnected, and the detection module 2 discretizes the output signal of the detector based on the ADC.

[0120] Step C3: Random number extraction: The transmitting end and the receiving end extract quantum random numbers through the post-processing module based on the sequence collected by the ADC and store them in the memory.

[0121] Step C4: quantum signal modulation: the sending end generates a corresponding modulation signal through the random number stored in the sending end, thereby realizing quantum signal modulation at the sending end.

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

[0123] Step C6: Data post-processing: The sender and receiver implement real-time data post-processing through parameter estimation, quantization negotiation, key error correction, and confidentiality enhancement. At this stage, the receiver data post-processing uses the quantum random numbers stored at the receiver for random base selection.

[0124] The present invention realizes the monolithic integration of CV-QKD and QRNG, solving the problem that the existing CV-QKD chip system security and integration are difficult to balance. At the same time, the quantum random number generation and the system shot noise calibration process are reused, saving ADC and detector resources, improving the system hardware utilization, and reducing system costs.

[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 protection scope of the present invention.

Claims

1. A monolithic integrated continuous variable quantum key distribution and quantum random number generation device, characterized in that: The monolithic integrated continuous variable quantum key distribution and quantum random number generation device comprises: a transmitting end and a receiving end, wherein the transmitting end is connected to the receiving end via an optical fiber transmission channel; Wherein, the sending end includes: Light source generating module 1, used for generating light signals at the transmitting end; The coupling module 1 is used to couple the optical signal generated by the light source generating module 1 to the light splitting module 1; The optical splitter 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; A modulation module, which modulates the received optical signal based on the modulation signal generated by the receiving driving 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 optical splitting module 2; The optical splitter module 2 is used to split the attenuated optical signal into two paths, one of which is output to the channel through the coupler 2, and the other 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, obtain an analog signal and transmit it to the analog-to-digital conversion module 1; The analog-to-digital conversion module 1 is used to convert the received analog signal into a digital signal and transmit it to the post-processing module 1; Post-processing module 1, used for modulation variance monitoring and random number generation, as well as parameter estimation, error correction and confidentiality enhancement; The driving module 1 generates a driving voltage based on the modulated driving signal generated by the receiving post-processing module 1, so as to drive the modulation module; Coupling module 2, coupling the quantum signal light into the optical fiber transmission channel; The receiving end comprises: The coupling module 3 receives the signal input from the optical fiber transmission channel and couples the channel quantum signal to the optical switch module; Optical switch module, used to turn off or turn on the input signal light to achieve shot noise calibration and quantum random number generation at the receiving end; The optical splitter module 3 is used to split the received signal light into two paths, one of which is output to the mixing module 1 and the other is output to the mixing module 2; Light source generating module 2, used for generating local oscillator light signal at the receiving end; The coupling module 4 couples the local oscillator light generated by the light source generating module 2 to the light splitting module 4; The optical 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 mixing module 1 and the other is output to the mixing module 2; Mixing module 1, used for coherent mixing of X component of CV-QKD system; Mixing module 2, used for coherent mixing of the P component of the CV-QKD system; Detection module 2, used for receiving the output signals of mixing module 1 and mixing module 2 to realize coherent detection; The analog-to-digital conversion module 2 converts the analog signal output by 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, error correction and confidentiality enhancement; The driving module 2 receives the optical switch driving signal generated by the post-processing module 2 and generates a driving voltage for driving the optical switch module.

2. The monolithic integrated continuous variable quantum key distribution and quantum random number generation device as claimed in claim 1, characterized in that: The modulation mode adopted by the modulation module includes: IQ modulation, amplitude modulation or phase modulation.

3. The monolithic integrated continuous variable quantum key distribution and quantum random number generation device as claimed in claim 1, characterized in that: The light source generating module 1 and the light source generating module 2 are input into the chip through a coupling module outside the chip, or are integrated inside the chip in a heterogeneous manner.

4. The monolithic integrated continuous variable quantum key distribution and quantum random number generation device as claimed in claim 1, characterized in that: The detection module 1 and the detection module 2 implement detection by homodyne detection or heterodyne detection.

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

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

7. A method for monolithic integrated continuous variable quantum key distribution and quantum random number generation, characterized in that: Using the device as claimed in any one of claims 1 to 5, the monolithic integrated continuous variable quantum key distribution and quantum random number generation method comprises: a random number extraction method of a post-processing module 1 at the sending end, a random number extraction method and a quantum key distribution method of a post-processing module 2 at the receiving end; Among them, the random number extraction method of the sending end post-processing module 1 is: Step A1: electrical noise calibration, by disconnecting the electrical signal of the light source generating module 1, making the optical signal input zero, the detection module 1 collects electrical noise, and obtains the electrical noise variance Var ele 1; Step A2: data sampling, the light source generating module 1 generates a light signal normally, the driving module 1 controls the modulated light signal output amplitude 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 the shot noise and the electrical noise, and the detector output signal is discretized and sampled based on the ADC, and its variance Var_snt_1 is obtained; Step A3: Entropy evaluation, evaluating the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) is the minimum entropy of the quantum component in the sampled signal or the conditional minimum entropy of the sampled sequence under known electrical noise conditions; Step A4: randomness extraction, based on the entropy evaluation result of step A3 and based on the data post-processing module 1 to achieve randomness extraction.

8. The method for monolithic integrated continuous variable quantum key distribution and quantum random number generation as claimed in claim 7, characterized in that: The random number extraction method of the post-processing module 2 of the receiving end is to multiplex the random number sequence of the shot noise monitoring stage, including: Step B1: electrical noise calibration, by disconnecting the electrical signal of the light source generating module 2, making the optical signal input zero, and disconnecting the optical signal input of the coupling module 3, then the detection module 2 collects the electrical noise, and calibrates the electrical noise variance Var_ele_2; Step B2: Data sampling, the driving 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, and discretizes and samples the detector output signal based on ADC, and obtains its variance Var_snt_2; Step B3: Entropy evaluation, evaluating the extractable quantum randomness H(X) in the ADC sampling sequence, where H(X) is the minimum entropy of the quantum component 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 result of step B3 and based on the data post-processing module 2 to achieve randomness extraction.

9. The method for monolithic integrated continuous variable quantum key distribution and quantum random number generation as claimed in claim 8, characterized in that: In step A4 and step B4, the randomness extraction method includes a Toeplitz matrix method, a hash function method, and a truncated XOR method.

10. The method for monolithic integrated continuous variable quantum key distribution and quantum random number generation as claimed in claim 7, characterized in that: The method for performing quantum key distribution by a device integrating continuous variable quantum key distribution and quantum random number generation on a single chip is: Step C1: electrical noise collection. Before the CV-QKD system works, the light source generation module 1 and the light source generation module 2 input zero to ensure that there is no light signal input. The detection module 1 and the detection module 2 respectively obtain the electrical noise variance of the detection module at the transmitting end and the receiving end; Step C2: Shot noise calibration, light source generation module 1 and light source generation module 2 generate light 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 output signal of the detector based on the ADC; At the receiving end, when the quantum signal of the transmitting end is detected to be 0, the optical switch module is immediately disconnected, and the detection module 2 discretizes the output signal of the detector based on the ADC; Step C3: random number extraction: the transmitting end and the receiving end respectively extract quantum random numbers based on the sequence collected by the ADC through the post-processing module 1 and the post-processing module 2 and store them in the memory; Step C4: quantum signal modulation, the sending end generates a corresponding modulation signal through the random number stored in the sending end, thereby realizing quantum signal modulation at the sending end; Step C5: key distribution, the sending end realizes quantum signal generation and modulation, and the receiving end realizes quantum signal detection; Step C6: Data post-processing. The sender and receiver implement real-time data post-processing through parameter estimation, quantization negotiation, key error correction and confidentiality enhancement. At this stage, the receiver's data post-processing will use the quantum random numbers stored at the receiver for random base selection.

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