Error mitigation device and method for continuous variable optical system

Abstract

The invention provides an error mitigation device and method for a continuous variable optical system, and the device is used for removing an error in a quantum signal generated by the continuous variable optical system, so as to obtain a measurement result of the quantum signal in the absence of phase damping noise. The error mitigation device at least comprises a noise modulation unit, a detection unit and a data processing unit, the noise modulation unit generates a plurality of voltage signals with different phases based on a plurality of noise parameters configured by a user, and performs phase modulation on quantum signals based on the generated voltage signals to obtain a plurality of phase-modulated quantum signals; the detection unit is used for detecting each phase-modulated quantum signal to obtain measurement results of all phase-modulated quantum signals; and the data processing unit is used for determining a measurement result of the quantum signal without phase damping noise by adopting an extrapolation method based on the noise parameters configured by the user and all measurement results detected by the detection unit.

Description

Technical Field

[0001] The present invention relates to the field of quantum computing, in particular to quantum error mitigation technology, and more particularly to an error mitigation device and method for a continuous variable optical system. Background Art

[0002] The operation of continuous-variable optical systems relies heavily on the accuracy of quantum signals, which are highly susceptible to environmental interference, such as temperature fluctuations and electromagnetic radiation. These interferences inevitably introduce noise, leading to deviations or even errors in the computational results. To eliminate errors in continuous-variable optical systems, quantum error mitigation technology has emerged. Quantum error mitigation is a technique for addressing system noise in medium-scale noisy quantum devices (NISQs). Its working principle is to first perform a measurement on a noisy quantum computer and then, through classical post-processing, estimate the quantum signal's noise-free measurement result.

[0003] Current research on quantum error mitigation in continuous-variable optical systems lags significantly behind that in discrete-variable systems. Existing approaches primarily focus on eliminating photon loss noise. Specifically, they employ probabilistic error cancellation (PEC) techniques, analytically deriving the inverse of the photon loss channel and decomposing it into a physically operable channel combination with negative coefficients (such as noiseless amplification and photon subtraction operations). Monte Carlo sampling is then used to achieve unbiased estimation. While these approaches can theoretically completely eliminate loss errors, their physical implementation relies on highly complex operations: 1) Noiseless amplification requires nondeterministic quantum processes (such as the subspace loop operation in the Zavatta scheme), resulting in resource consumption that scales exponentially with the number of modes; 2) Photon subtraction requires a multi-port beam splitter and a photon number-resolved detector (PNRD), resulting in complex experimental setups and poor scalability; 3) these approaches are only applicable to specific initial states (such as cat states and single-photon states). More critically, existing research has almost completely overlooked another important noise source in continuous-variable systems: phase damping noise (originating from phase decoherence caused by environmental coupling), for which no effective mitigation solutions exist.

[0004] In summary, the existing quantum error mitigation techniques have three major problems. First, the research scope is limited, only focusing on photon loss noise, lacking systematic research on phase damping noise, resulting in a gap in continuous variable noise coverage. Second, the experimental implementation barrier is prominent. The mainstream PEC scheme relies on photon number resolving detection and non-deterministic noiseless amplification, which far exceeds the basic linear optical capability, and must be equipped with expensive and complex devices such as quantum memory and high-precision single-photon detector, significantly increasing the technical difficulty and cost. Third, the method has poor universality, and the inverse channel decomposition needs to be tailored for specific initial states such as squeezed vacuum states and cat states, which is difficult to generalize to any continuous variable quantum state. Therefore, there is an urgent need for a quantum error mitigation scheme that can simultaneously suppress photon loss and phase damping noise, without complex quantum devices, and is applicable to any continuous variable quantum state.

[0005] It should be noted that: the background art is only used to introduce the related information of the present application, so as to help understand the technical scheme of the present application, but does not mean that the related information must be prior art. In the absence of evidence that the related information has been disclosed before the filing date of the present application, the related information should not be regarded as prior art. SUMMARY

[0006] Therefore, the purpose of the present application is to overcome the defects of the prior art, and to provide an error mitigation device and method for a continuous variable optical system.

[0007] The purpose of the present application is achieved by the following technical scheme:

[0008] According to a first aspect of the present invention, an error mitigation device for a continuous variable optical system is proposed, wherein the continuous variable optical system is used to continuously generate the same quantum signal, and each generated quantum signal contains an error caused by the phase damping noise of the continuous variable optical system. The error mitigation device is used to remove the error in the quantum signal generated by the continuous variable optical system to obtain a measurement result of the quantum signal in the absence of phase damping noise. The error mitigation device includes a noise modulation unit, a detection unit and a data processing unit, wherein the noise modulation unit is used to receive multiple noise parameters configured by a user and generate multiple voltage signals with different phases based on the configured noise parameters, and the noise modulation unit is used to receive the quantum signal generated by the continuous variable optical system and phase modulate the received quantum signal based on the generated voltage signal to obtain multiple phase-modulated quantum signals, wherein each noise parameter corresponds to multiple voltage signals, and each voltage signal is used to phase modulate a quantum signal; the detection unit is used to detect each phase-modulated quantum signal to obtain measurement results of all phase-modulated quantum signals; and the data processing unit is used to determine the measurement result of the quantum signal generated by the continuous variable optical system in the absence of phase damping noise by an extrapolation method based on all noise parameters configured by the user and all measurement results detected by the detection unit.

[0009] Preferably, the noise modulation unit is configured with a noise parameter input module, a random voltage generation module and a phase modulation module, wherein: the noise parameter input module is used to provide noise parameter configuration services so that users can configure multiple noise parameters; the random voltage generation module is used to randomly generate multiple voltage signals corresponding to each noise parameter input by the user; the phase modulation module is used to receive a quantum signal generated by a continuous variable optical system, and phase modulate the received quantum signal based on the voltage signal generated by the random voltage generation module, wherein one voltage signal is used to phase modulate one quantum signal.

[0010] Preferably, the phases of the multiple voltage signals corresponding to each noise parameter generated by the random voltage generation module obey Gaussian distribution.

[0011] Preferably, the phase modulation module is configured to perform phase modulation on the quantum signal in the following manner:

[0012]

[0013] in, Indicates the user configured Noise parameters, The density matrix of the quantum state representing the quantum signal in the absence of phase damping noise, The noise parameter of the phase modulator is expressed as The density matrix of the quantum signal obtained by phase modulating the quantum signal with the corresponding voltage signal, The rows of elements in the density matrix representing the quantum signal, The columns of elements in the density matrix representing the quantum signal.

[0014] Preferably, the detection unit is configured to: use a balanced homodyne detector to perform conventional homodyne detection on the quantum signal after phase damping modulation to obtain a measurement result of the quantum signal after phase modulation.

[0015] Preferably, the extrapolation method is: based on all measurement results detected by the detection unit, determine the average value of the measurement results corresponding to each noise parameter, wherein the average value of the measurement results corresponding to each noise parameter is the average value of the measurement results of all quantity signals obtained after phase modulation of the voltage signal corresponding to the noise parameter; establish a group of equations based on the average value of all determined measurement results and the noise parameter configured by the user; solve the established group of equations to obtain the measurement results of the quantum signal in the absence of phase damping noise.

[0016] Preferably, the set of equations to be solved is:

[0017]

[0018] in, Indicates the user configured The noise parameter corresponds to the average value of the measurement results of all phase-modulated quantum signals, Indicates the user configured Noise parameters, represents the measurement result of the quantum signal without phase damping noise, Indicates the unknown coefficients, Indicates the total number of noise parameters entered by the user, Indicates the preset precision.

[0019] According to a second aspect of the present invention, an error mitigation method for a continuous variable optical system is proposed, which is used to remove errors in a quantum signal generated by a target continuous variable optical system to obtain a measurement result of the quantum signal generated by the target continuous variable optical system in the absence of phase damping noise. The method comprises: step S1, obtaining the error mitigation device described in any one of the first aspects of the present invention and configuring multiple noise parameters; step S2, causing the target continuous variable optical system to continuously generate the same quantum signal, and using the error mitigation device after the noise parameters are configured in step S1 to remove errors in the quantum signal to obtain a measurement result of the quantum signal in the absence of phase damping noise.

[0020] According to a third aspect of the present application, a computer readable storage medium is provided, having stored thereon a computer program, the computer program being executable by a processor to implement the method according to the second aspect of the present application.

[0021] According to a fourth aspect of the present application, an electronic device is provided, comprising: one or more processors; and a memory, wherein the memory is configured to store executable instructions; and the one or more processors are configured to implement the method according to the second aspect of the present application via execution of the executable instructions.

[0022] Compared with the prior art, the present application has the advantages that:

[0023] The present application provides an error mitigation device for a continuous variable optical system, which can accurately regulate phase damping noise of different intensities by relying only on linear optical devices, and can effectively estimate and mitigate phase damping errors in a quantum signal generated by a continuous variable optical system without complex quantum devices by extrapolating measurement results under multiple noise levels, thereby realizing low-cost and easily expandable continuous variable quantum signal error suppression. BRIEF DESCRIPTION OF DRAWINGS

[0024] The embodiments of the present application will be further described below with reference to the drawings, in which:

[0025] Figure 1 FIG. 1 is a structural schematic diagram of an error mitigation device for a continuous variable optical system according to an embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below through specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0027] As mentioned in the background section, the existing quantum error mitigation technology has three major problems. First, the research scope is limited, focusing only on photon loss noise, and lacking systematic research on phase damping noise, resulting in a gap in continuous variable noise coverage. Second, the experimental implementation barrier is prominent. The mainstream PEC scheme relies on photon number resolving detection and nondeterministic noiseless amplification, which far exceeds the basic linear optical capability, and must be equipped with expensive and complex devices such as quantum memory and high-precision single-photon detector, significantly increasing the technical difficulty and cost. Third, the method has poor universality, and the inverse channel decomposition needs to be tailored for specific initial states such as squeezed vacuum states and cat states, which is difficult to generalize to any continuous variable quantum state. Therefore, there is an urgent need for a quantum error mitigation scheme that can simultaneously suppress photon loss and phase damping noise, does not require complex quantum devices, and is applicable to any continuous variable quantum state.

[0028] In order to solve the above problems, the application provides an error mitigation scheme for a continuous variable optical system, which can accurately regulate phase damping noise of different intensities by only relying on linear optical devices, and can obtain the measurement result of a quantum signal without phase damping noise by extrapolating the measurement results under multiple noise levels, without the need of complex quantum devices to effectively estimate and mitigate phase damping errors.

[0029] In order to better illustrate the feasibility of the application, the forming process of the application scheme will be briefly described below.

[0030] Through in-depth research on the continuous variable optical system, the inventors found that on the one hand, the extrapolation method widely used in discrete variable systems (such as Richardson extrapolation) has not been effectively migrated to the continuous variable field; on the other hand, through in-depth analysis of the physical nature of the phase damping noise, the phase damping noise is equivalent to the linear optical Gaussian random phase modulation, so that the quantum quantum signal can be modulated under multiple noise intensities by continuously scaling the noise intensity, and the measurement result of the modulated quantum signal can be obtained by using the extrapolation method to deduce the measurement result of the quantum signal without phase damping noise. The random Gaussian phase damping applied to the quantum state can be represented by the following formula:

[0031]

[0032] Among them, represents the density matrix of the quantum state of the quantum signal without phase damping noise, represents the noise parameter, is the photon number operator, represents applying a phase to an optical mode, and further, the following formula can be obtained by deducing the above formula:

[0033]

[0034] Among them, the formula on the right side of the second equal sign is obtained by Fourier transforming the Gaussian function in the formula on the right side of the first equal sign, and the result is still a Gaussian function. In addition, since the phase damping noise is equivalent to the linear optical Gaussian random phase modulation, the application directly controls the phase damping intensity based on the Gaussian random distribution, and can realize the continuous scaling of the noise intensity. Based on the above finding, the quantum signal can be adjusted under multiple noise intensities, and the adjusted quantum signal can be measured, and then the extrapolation method is used to calculate the measurement result of the quantum signal without the influence of the phase damping noise.

[0035] According to one embodiment of the present invention, based on the above-mentioned derivation results, the present invention proposes an error mitigation device for a continuous variable optical system, wherein the continuous variable optical system is used to continuously generate the same quantum signal, and each generated quantum signal has an error caused by the fixed phase damping noise of the continuous variable optical system. The error mitigation device proposed by the present invention is used to remove the error in the quantum signal generated by the continuous variable optical system to obtain the measurement result of the quantum signal in the absence of phase damping noise. Figure 1 The error mitigation device proposed in the present invention includes a noise modulation unit, a detection unit and a data processing unit, wherein the noise modulation unit is used to receive multiple noise parameters configured by a user, and generate multiple voltage signals with different phases based on the configured noise parameters, and the noise modulation unit is used to receive a quantum signal generated by a continuous variable optical system, and phase-modulate the received quantum signal based on the generated voltage signal to obtain multiple phase-modulated quantum signals, wherein each noise parameter corresponds to multiple voltage signals, and each voltage signal is used to phase-modulate a quantum signal; the detection unit is used to detect each phase-modulated quantum signal to obtain measurement results of all phase-modulated quantum signals; and the data processing unit is used to determine the measurement results of the quantum signal generated by the continuous variable optical system in the absence of phase damping noise by using an extrapolation method based on all noise parameters configured by the user and all measurement results detected by the detection unit.

[0036] In order to better understand the present invention, the present invention is described in detail below with reference to specific embodiments.

[0037] According to one embodiment of the present invention, still referring to Figure 1 In the error mitigation device proposed in the present invention, the noise modulation unit includes a noise parameter input module, a random voltage generation module, and a phase modulation module. The noise parameter input module is configured to provide a noise parameter configuration service, allowing users to configure multiple noise parameters. The random voltage generation module is configured to randomly generate multiple voltage signals corresponding to each noise parameter input by the user. The phase modulation module is configured to receive a quantum signal generated by a continuous variable optical system and perform phase modulation on the received quantum signal based on the voltage signal generated by the random voltage generation module. One voltage signal is used to phase modulate one quantum signal.

[0038] According to one embodiment of the present invention, in the present invention, the phases of the multiple voltage signals corresponding to each noise parameter generated by the random voltage generation module obey Gaussian distribution. Specifically, the voltage generator generates a set of voltage signals according to a configured noise parameter to obtain multiple sets of voltage signals, wherein the phase distribution of the generated voltage signals should satisfy , is a Gaussian random distribution, represents the noise parameter, Represents the phase. Assuming Γ=0.1 as an example, the generated voltage signal phase θ satisfies the Gaussian distribution probability density function: .

[0039] According to one embodiment of the present invention, in the present invention, the phase modulation module loads the voltage signal generated by the random voltage generation module and performs phase modulation on the quantum signal passing through the phase modulation module, so that the non-diagonal elements of the density matrix of the quantum signal are in accordance with Attenuation is performed to complete the phase modulation of the quantum signal, wherein the phase modulation module only phase modulates one quantum signal each time a voltage signal is loaded. Specifically, the phase modulation process of the quantum signal by the phase modulation module can be expressed by the following formula:

[0040]

[0041] in, Indicates the user configured Noise parameters, represents the density matrix of the quantum state of the quantum signal in the absence of phase damping noise, The noise parameter of the phase modulator is expressed as The density matrix of the quantum signal obtained by phase modulating the quantum signal with the corresponding voltage signal, The rows of elements in the density matrix representing the quantum signal, The columns of elements in the density matrix representing the quantum signal.

[0042] In order to facilitate understanding of the modulation process of the quantum signal by the phase modulation module, the following will be described in detail with examples.

[0043] Assume that the quantum signal is a coherent state (A coherent state is a state where the number of photons is uncertain but there is a stable phase correlation.) The density matrix of the quantum signal is ρ = , matrix element , when the noise parameter and When , the attenuation factor is The matrix element is When the noise parameter and When (for example ), the attenuation factor is: , matrix element .

[0044] According to one embodiment of the present application, a detection unit is arranged at the output end of the phase modulation module, and is used to detect the phase-modulated quantum signal to obtain the measurement result of the phase-modulated quantum signal. In the present application, the detection unit uses a balanced homodyne detector to perform conventional homodyne detection on the phase-damped quantum signal to obtain the measurement result of the phase-modulated quantum signal. It should be noted that the detection unit can also be constructed by using other detectors with conventional homodyne detection as the detection mode.

[0045] According to one embodiment of the present application, the plurality of quantum signals generated by the continuous variable optical system sequentially pass through the phase modulation of the noise modulation unit and the detection of the detection unit, and the measurement results of the plurality of phase-modulated quantum signals can be obtained. Each quantum signal corresponds to a voltage signal of one noise parameter. In the present application, the data processing unit obtains a linear equation set for solving the measurement result of the quantum signal without phase-damping noise based on the Richardson extrapolation formula, and solves the constructed linear equation set to obtain the measurement result of the quantum signal without phase-damping noise. First, based on all the noise parameters configured by the user and all the measurement results detected by the detection unit, a matrix equation is constructed as follows:

[0046]

[0047] Then, the linear equation set for solving the measurement result of the quantum signal without phase-damping noise can be obtained by performing matrix operation on the above formula, and the linear equation set is represented as follows:

[0048]

[0049] wherein, represents the average value of all the measurement results corresponding to the i-th noise parameter configured by the user, represents the i-th noise parameter configured by the user, represents the measurement result of the quantum signal without phase-damping noise, represents the i-th unknown coefficient, represents the total number of noise parameters input by the user, represents the preset precision, represents the high-order remainder, and it should be noted that the remainder can be ignored in the calculation of the present application, and the measurement result of the quantum signal without phase-damping noise is solved by solving the equation set.

[0050] ​​​According to one embodiment of the present invention, based on the above-mentioned error mitigation device for a continuous variable optical system, the present invention proposes an error mitigation method for a continuous variable optical system implemented by the device. In summary, the method includes: step S1, obtaining the error mitigation device described above and configuring multiple noise parameters; step S2, controlling the target continuous variable optical system to continuously generate the same quantum signal, and at the same time using the error mitigation device with the noise parameters configured in step S1 to remove the error in each quantum signal, so as to obtain the measurement result of the quantum signal in the absence of phase damping noise.

[0051] To facilitate understanding of the process of performing error mitigation on a continuous variable optical system using an error mitigation device for a continuous variable optical system proposed by the present invention, a description will be given below with reference to specific examples.

[0052] Assume that there is a continuous variable optical system for quantum key distribution, and the quantum signal generated by the system has fixed phase damping noise. The steps required to obtain the measurement result of the quantum signal generated by the continuous variable optical system in the absence of phase damping noise using the error mitigation device proposed in the present invention include steps 1, 2, and 3, where the operations performed in each step are described as follows.

[0053] Step 1: Device preparation and noise parameter configuration: Connect the quantum signal output of the continuous variable optical system to the input of the noise modulation unit (including the noise parameter input module, random voltage generation module, and phase modulation module) of the error mitigation device. The output of the noise modulation unit is connected to the detection unit (a balanced homodyne detector). The detection unit is connected to the data processing unit (a computer running the MATLAB data processing program) via a data cable. Through the noise parameter input module, the user configures three noise parameters: Γ1 = 0.1, Γ2 = 0.3, and Γ3 = 0.5 (k = 3). The precision r in the extrapolation method is also preset to 2. It should be understood that the number, values, and precision r of the above noise parameters are exemplary and are configured by the user in practice. The greater the number of noise parameters configured and the greater the precision value in the extrapolation method, the higher the precision of the quantum signal measurement result obtained when there is no phase damping noise.

[0054] Step 2: Noise modulation and quantum signal detection. The random voltage generation module generates 100 voltage signals with phases that obey the Gaussian distribution for each noise parameter. Taking Γ1=0.1 as an example, the generated voltage signal phase θ satisfies the Gaussian distribution probability density function: , Similarly, the voltage signal group corresponding to Γ2 and Γ3 is generated. The continuous variable optical system continuously generates the same quantum signal, and the quantum signal enters the phase modulation module in sequence. The phase modulation module loads the voltage signal one by one to perform phase modulation on the quantum signal. For example, when a voltage signal corresponding to Γ1 is loaded, according to the formula The quantum signal is phase-damped modulated, and 300 (3 noise parameters × 100 voltage signals) phase-modulated quantum signals are finally obtained. A balanced homodyne detector is used to perform homodyne detection on each modulated quantum signal to obtain the measurement results of the quantum state of each modulated quantum signal. ( Corresponding to 100 measurement results), 、 and transmits all measurement results to the data processing unit.

[0055] Step 3: Data processing and measurement result solution: The data processing unit averages the 100 measurement results corresponding to each noise parameter to obtain: =0.1 corresponding to the average value =0.85 (0.85 is an assumed value, actually calculated from detection data), =0.3 corresponding to the average value =0.62, =0.5 corresponding to the average value =0.41. According to the extrapolation formula Set up the system of equations:

[0056]

[0057] Solving the above linear equations using matrix operations or the least squares method yields the measurement result of ⟨O>=0.98 for the quantum signal generated by the continuous variable optical system in the absence of phase damping noise. It should be understood that the parameters in the above example are merely illustrative; in specific implementations, actual detected data will prevail.

[0058] In summary, the error mitigation device for continuous-variable optical systems proposed in the present invention can precisely control phase damping noise of different intensities by relying solely on linear optical devices. By extrapolating the measurement results under multiple noise levels, the phase damping error can be effectively estimated and mitigated without the need for complex quantum devices, thereby achieving error suppression of quantum signals generated by low-cost, easily scalable continuous-variable optical systems.

[0059] It should be noted that although the above describes the various steps in a specific order, it does not mean that the steps must be performed in the above specific order. In fact, some of these steps can be executed concurrently or even in a different order as long as the required functions can be achieved.

[0060] The present invention may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present invention.

[0061] A computer-readable storage medium may be a tangible device that holds and stores instructions used by an instruction execution device. Computer-readable storage media may include, for example, but is not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove having instructions stored thereon, and any suitable combination thereof.

[0062] While various embodiments of the present invention have been described above, the above descriptions are intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An error mitigation device for a continuous variable optical system, wherein the continuous variable optical system is used to continuously generate the same quantum signal, and each generated quantum signal contains errors caused by phase damping noise of the continuous variable optical system. The error mitigation device is used to remove the errors in the quantum signal generated by the continuous variable optical system to obtain a measurement result of the quantum signal in the absence of phase damping noise, characterized in that: The error mitigation device includes a noise modulation unit, a detection unit and a data processing unit, wherein: The noise modulation unit is used to receive multiple noise parameters configured by a user, and generate multiple voltage signals with different phases based on the configured noise parameters. The noise modulation unit is also used to receive a quantum signal generated by a continuous variable optical system, and phase modulate the received quantum signal based on the generated voltage signal to obtain multiple phase-modulated quantum signals, wherein each noise parameter corresponds to multiple voltage signals, and each voltage signal is used to phase modulate one quantum signal. The detection unit is used to detect each phase-modulated quantum signal to obtain measurement results of all phase-modulated quantum signals; The data processing unit is used to determine the measurement result of the quantum signal generated by the continuous variable optical system in the absence of phase damping noise by using an extrapolation method based on all noise parameters configured by the user and all measurement results detected by the detection unit.

2. The device according to claim 1, characterized in that The noise modulation unit is configured with a noise parameter input module, a random voltage generation module and a phase modulation module, wherein: The noise parameter input module is used to provide noise parameter configuration services to facilitate users to configure multiple noise parameters; The random voltage generation module is used to randomly generate a plurality of voltage signals corresponding to each noise parameter input by the user; The phase modulation module is used to receive a quantum signal generated by a continuous variable optical system and perform phase modulation on the received quantum signal based on a voltage signal generated by a random voltage generation module, wherein one voltage signal is used to perform phase modulation on one quantum signal.

3. The device according to claim 2, characterized in that The phases of the multiple voltage signals corresponding to each noise parameter generated by the random voltage generation module obey Gaussian distribution.

4. The device according to claim 3, characterized in that The phase modulation module is configured to perform phase modulation on the quantum signal in the following manner: in, Indicates the user configured Noise parameters, The density matrix of the quantum state representing the quantum signal in the absence of phase damping noise, The noise parameter of the phase modulator is expressed as The density matrix of the quantum signal obtained by phase modulating the quantum signal with the corresponding voltage signal, The rows of elements in the density matrix representing the quantum signal, The columns of elements in the density matrix representing the quantum signal.

5. The device according to claim 4, characterized in that The detection unit is configured to: use a balanced homodyne detector to perform conventional homodyne detection on the quantum signal after phase damping modulation to obtain a measurement result of the quantum signal after phase modulation.

6. The device according to claim 5, characterized in that The extrapolation method is: Determine, based on all measurement results detected by the detection unit, an average value of the measurement results corresponding to each noise parameter, wherein the average value of the measurement results corresponding to each noise parameter is an average value of the measurement results of all quantity signals obtained after phase modulation of the voltage signal corresponding to the noise parameter; A system of equations is established based on the average of all determined measurement results and the noise parameters configured by the user; The established set of equations is solved to obtain the measurement results of the quantum signal in the absence of phase damping noise.

7. The device according to claim 6, characterized in that The set of equations to be solved is: in, Indicates the user configured The noise parameter corresponds to the average value of the measurement results of all phase-modulated quantum signals, Indicates the user configured Noise parameters, represents the measurement result of the quantum signal without phase damping noise, Indicates the unknown coefficients, Indicates the total number of noise parameters entered by the user, Indicates the preset precision.

8. An error mitigation method for a continuous variable optical system, for removing errors in a quantum signal generated by a target continuous variable optical system to obtain a measurement result of the quantum signal generated by the target continuous variable optical system in the absence of phase damping noise, characterized in that: The method comprises: Step S1: Obtain the error mitigation device according to any one of claims 1 to 7, and configure multiple noise parameters; Step S2: The target continuous variable optical system is made to continuously generate the same quantum signal, and the error mitigation device after the noise parameters are configured in step S1 is used to remove the error in the quantum signal to obtain a measurement result of the quantum signal in the absence of phase damping noise.

9. A computer-readable storage medium, characterized in that A computer program is stored thereon, and the computer program can be executed by a processor to implement the method of claim 8.

10. An electronic device, characterized in that: include: one or more processors; as well as a memory, wherein the memory is used to store executable instructions; The one or more processors are configured to implement the method of claim 8 by executing the executable instructions.

Images