Configuration acquisition method and system for realizing maximum violation even setting CHSH measurement device

Abstract

The invention discloses a configuration acquisition method and system for realizing a maximum violation even setting CHSH measurement device, and relates to the field of quantum information processing. Quantum state information of two-dimensional non-maximum entanglement particles A and B is acquired, and associated parameters are calculated; correlation mapping is constructed, and particle B measurement direction parameters are mapped to an ellipsoid curved surface from a Bloch sphere space; 2n + 1 endpoints including a centrosymmetric endpoint pair in the same plane of the ellipsoid curved surface are connected to form a broken line path of 2n line segments, and the length formula of the broken line path is equal to a formula for setting the maximum value of a CHSH correlation function in 2n; iteratively searching 2n endpoints to maximize the broken line path length, and taking the maximum value of the corresponding correlation function; and mapping the optimal endpoint position into measurement direction configuration of the particles A and B, setting a measurement device and performing measurement to obtain a measurement value for verifying CHSH inequality quantum violation. According to the method, the problem of setting the maximum value of the CHSH correlation function by an even number is converted into the problem of solving the maximum value of the broken line path length, and the optimal measurement scheme is obtained through simple numerical fitting.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of quantum information processing, and particularly relates to a configuration acquisition method and system for realizing a maximum violation even setting CHSH measurement device. BACKGROUND

[0002] In a quantum information processing and quantum communication system, the configuration mode of a measurement device directly affects the evaluation result of the correlation characteristics of a particle system. Under the condition of multiple measurement settings, it is usually necessary to reasonably configure multiple measurement directions to obtain a measurement result that satisfies a specific correlation evaluation index. Among them, the even chain measurement structure is concerned due to its high correlation evaluation sensitivity when the number of measurement settings increases.

[0003] Under ideal conditions, when the particle system is in a highly entangled state, the configuration of the measurement device usually has a relatively clear symmetric structure, and the selection of related parameters is relatively simple. However, in actual application scenarios, due to the influence of quantum state preparation errors, transmission losses, and environmental disturbances, the particle system is often in a non-maximal entangled state. Under this condition, the relationship between the measurement device configuration and the correlation parameter is significantly complicated, and the optimal selection of the measurement direction parameter is difficult to obtain through simple symmetry analysis.

[0004] For the even chain measurement structure under the condition of a non-maximal entangled state, the existing technology usually calculates and optimizes the correlation parameter based on analytical derivation or numerical simulation. For example, by scanning the multiple measurement direction parameters point by point, the corresponding correlation parameter values are calculated, and the optimal configuration scheme is selected from them. However, with the increase in the number of measurement settings, the dimension of the parameter space to be traversed rapidly increases, and the computational complexity significantly increases, making it difficult to obtain a globally optimal measurement device configuration under limited computing resources.

[0005] In addition, the existing method usually searches for the measurement direction directly in a high-dimensional parameter space, without fully utilizing the geometric constraint relationship implied between the measurement parameters, resulting in a large amount of redundant calculation in the search process and low configuration acquisition efficiency. At the same time, the existing technology lacks a unified and structured configuration acquisition framework, making it difficult to convert the correlation parameter optimization problem under any even chain measurement structure into a calculation process convenient for engineering implementation, thereby limiting the application of such measurement structures in actual quantum information systems.

[0006] The experimental measurement process of the even chain CHSH correlation parameter is described as follows: the expression of the even chain CHSH correlation parameter is given as:

[0007] (1);

[0008] If the measured value of the correlation parameter is greater than , then the nonlocality of the system is proved. In the actual test of the experiment, the expectation function in formula (1)

[0009] (2).

[0010] coincidence counts is the joint measurement count of projecting the A particle to state and projecting the B particle to state . Wherein, the two-dimensional particle state , can be expressed as:

[0011] (3).

[0012] Therefore, there is an urgent need for a measurement device configuration acquisition method for even-numbered chain measurement structure under the condition of non-maximal entangled state, which can effectively reduce the parameter search dimension on the basis of clearly defining the measurement parameter constraint relationship, and convert the optimization problem of related parameters into a clear structure and easy-to-implement calculation process, so as to improve the efficiency and practicability of measurement device configuration acquisition. SUMMARY

[0013] In view of the above problems, the present application provides a configuration acquisition method and system for realizing maximum violation even-numbered CHSH measurement device, which converts the optimization problem of even-numbered CHSH related parameters into the optimization problem of geometric path length through geometric mapping, and efficiently acquires the optimal measurement device configuration suitable for non-maximal entangled state through a structured parameter search process, so as to reduce the configuration search complexity and improve the application feasibility of the measurement device in the actual quantum information processing system.

[0014] On the one hand, the configuration acquisition method for realizing maximum violation even-numbered CHSH measurement device is implemented, and the specific steps are as follows:

[0015] S1, acquiring quantum state information of a pair of two-dimensional non-maximal entangled particles A and particle B, and determining a related parameter representing the degree of entanglement based on the quantum state information;

[0016] S2, constructing a related mapping relationship according to the related parameter, and mapping the measurement direction parameter of particle B from the Bloch sphere space to an ellipsoid surface by using the related mapping relationship;

[0017] S3, taking 2n+1 points on the same plane of the ellipsoid surface as endpoints; the endpoints include endpoint pairs formed by two endpoints in central symmetric relation with respect to the ellipsoid center of the ellipsoid surface; taking one endpoint of an endpoint pair as a starting point and the other endpoint of the endpoint pair as a terminal point, sequentially connecting all the endpoints to obtain a polyline path including 2n line segments; the length formula of the polyline path is equivalent to the maximum value formula of the 2n setting CHSH inequality correlation function of particles A and B;

[0018] S4, taking 2n endpoints formed by any one endpoint of an endpoint pair and other endpoints; taking the length of the polyline path as a target function to iteratively search the positions of the 2n endpoints to obtain the maximum value of the length of the polyline path; the maximum value formula of the corresponding correlation function is maximized;

[0019] S5, mapping the corresponding endpoint positions when the maximum value of the length of the polyline path is obtained into the measurement direction configuration of particles A and B;

[0020] S6, setting a quantum measurement device according to the measurement direction configuration to jointly measure particles A and B to obtain measurement values for verifying the quantum violation behavior of the 2n setting CHSH inequality.

[0021] Preferably, the correlation parameter is concurrency; the concurrency is obtained by calculation based on a probability amplitude.

[0022] Preferably, the correlation mapping relationship is a correlation matrix in the form of a diagonal matrix; the diagonal elements of the diagonal matrix are 、 and -1; wherein, represents the concurrency.

[0023] Preferably, the mapping of the corresponding endpoint positions when the maximum value of the length of the polyline path is obtained into the measurement direction configuration of particles A and B is that the measurement direction of particle B is determined by the vector from the ellipsoid center to each endpoint of the polyline path, and the measurement direction of particle A is determined by the direction of the line connecting adjacent endpoints in the polyline path.

[0024] Preferably, the 2n setting CHSH inequality correlation function of particles A and B is represented as:

[0025] ;

[0026] When ;

[0027] wherein, represents the measurement vector of the 2n points selected on the ellipsoid surface; represents the correlation mapping relationship. Indicates the definition symbol; This represents the measurement vectors of the 2n points selected on the ellipsoid in the Bloch sphere of particle B; This represents the corresponding measurement vector in the Bloch sphere of particle A; Indicates an association function; This represents the measurement vector on the ellipsoidal surface of the endpoint that forms an endpoint pair with the 2nth endpoint.

[0028] Preferably, the measurement vector of particle A is represented as follows:

[0029] , , , , ;

[0030] in, This indicates taking the modulus.

[0031] Preferably, the formula for setting the maximum value of the CHSH inequality correlation function in 2n is expressed as:

[0032] ;

[0033] in, This represents the maximum value of the correlation function; This indicates taking the modulus.

[0034] Preferably, the principal axis of the ellipsoidal surface is aligned with a preset reference axis; when the maximum length of the broken line path is obtained, the corresponding endpoint is located on the elliptical curve formed by the intersection of the ellipsoidal surface and the plane containing the preset reference axis.

[0035] On the other hand, the configuration acquisition system for the CHSH measurement device that realizes the maximum even-number violation setting includes the following:

[0036] The correlation parameter acquisition module is used to acquire the quantum state information of a pair of two-dimensional non-maximally entangled particles A and B, and determine the correlation parameters characterizing the degree of entanglement based on the quantum state information.

[0037] The spatial mapping module is used to construct an association mapping relationship based on the association parameters, and to use the association mapping relationship to map the measurement direction parameters of particle B from the Bloch sphere space to an ellipsoidal surface.

[0038] The broken line path construction module is used for taking 2n+1 points on the same plane of the ellipsoid surface as end points; the end points include an end point pair formed by two end points in a central symmetric relationship with respect to the ellipsoid center of the ellipsoid surface; one end point of the end point pair is taken as a starting point, and the other end point of the end point pair is taken as an ending point, and all the end points are sequentially connected to obtain a broken line path including 2n line segments; and a length formula of the broken line path is equivalent to a 2n setting CHSH inequality correlation function maximum value formula of the particle A and the particle B.

[0039] The iteration module is used for taking any end point in the end point pair and other end points to form 2n end points; a length of the broken line path is taken as a target function to perform iterative search on positions of the 2n end points, to obtain a maximum value of the length of the broken line path; and a maximum value formula of the corresponding correlation function maximum value is obtained.

[0040] The measurement configuration acquisition module is used for mapping the corresponding end point positions into a measurement direction configuration of the particle A and the particle B when the maximum value of the length of the broken line path is obtained.

[0041] The measurement module is used for setting a quantum measurement device according to the measurement direction configuration, performing joint measurement on the particle A and the particle B, and obtaining a measurement value of quantum violation behavior for verifying the 2n setting CHSH inequality.

[0042] Compared with the prior art, the present application has the following beneficial effects:

[0043] (1) The present application converts an optimization problem of an even chain type CHSH correlation parameter into an optimization problem of a broken line path length in an ellipsoid surface, so that an originally complex parameter optimization process has a clear geometric structure, and is convenient for engineering implementation and algorithm design.

[0044] (2) The present application proposes a unified acquisition method for a measurement configuration problem under a non-maximum entangled state condition, does not depend on a specific symmetry assumption, and has good universality.

[0045] (3) The present application optimizes configuration parameters by using an iterative search method, does not limit a specific optimization algorithm form, is suitable for various parameter search and optimization implementation modes, and has good expansibility.

[0046] (4) The measurement device configuration acquisition method provided by the present application can be directly applied to a quantum communication, quantum measurement and related information processing system, has high engineering application value, and is conducive to improving device configuration efficiency under a multi-measurement setting condition. BRIEF DESCRIPTION OF DRAWINGS

[0047] The present application will be further described in detail below with reference to the drawings;

[0048] Figure 1This is a flowchart illustrating the configuration acquisition method for the CHSH measurement device with the maximum even number violation setting according to an embodiment of the present invention.

[0049] Figure 2 This is a schematic diagram illustrating the geometric model of the correlation function of the configuration acquisition method for the CHSH measurement device with maximum violation of even numbers in an embodiment of the present invention; wherein, (a) represents a schematic diagram of the Bloch spheres of two particles; (b) represents a schematic diagram of the correlation matrix K acting on the Bloch sphere of particle B.

[0050] Figure 3 An experimental measurement device applicable to the orbital angular momentum degree of freedom of a photon, which is an embodiment of the present invention for obtaining the configuration of a CHSH measurement device with the maximum violation of even numbers;

[0051] Figure 4 This is a schematic diagram of the total length of 2n broken lines (gray) formed by 2n+1 points inscribed in the mapped ellipse, representing the configuration acquisition method for the CHSH measurement device with the maximum violation of even numbers in this embodiment of the invention; wherein, in this embodiment, 2n is taken as 6;

[0052] Figure 5 This is a structural block diagram of the configuration acquisition system for the CHSH measurement device that implements the maximum even number violation setting according to an embodiment of the present invention. Detailed Implementation

[0053] The present invention will be further described below through specific embodiments. These embodiments illustrate how, under non-maximum entanglement conditions, the optimal measurement device configuration corresponding to even-numbered chain CHSH correlation parameters is obtained according to the method of the present invention. The mathematical expressions involved are used to clarify the implementation principle of the technical solution, and not to limit the scope of protection of the present invention.

[0054] like Figure 1 As shown, the method for obtaining the configuration of the CHSH measurement device with the maximum even number violation setting mainly includes the steps of obtaining associated parameters, association mapping, path construction, parameter search, and measurement configuration generation. The specific steps are as follows:

[0055] Let a pair of correlation parameters (concurrency) be... Two pure states of particles ∈ (0,1], where =0 indicates a non-entangled state. =1 indicates maximizing the entanglement state. In this embodiment, a photon is used as an example of a particle, and its quantum state can be represented as:

[0056] (4);

[0057] The correlation matrix corresponding to this quantum state can be represented as a diagonal matrix: In the Bloch sphere representation, the measurement states of particles A and B correspond to the unit vectors pointing from the center of the sphere to the surface of the sphere, respectively, and are expressed as follows: ,like Figure 2 As shown in (a). Expectation function Expressed as measurement vector Inner product with the incidence matrix K: Then equation (1) can be expressed as:

[0058] (5);

[0059] To facilitate subsequent optimization of the correlation parameters, this embodiment introduces a measurement vector mapped by the correlation matrix: when Under the influence of the correlation matrix, the measurement vector of particle B, after mapping, has its endpoint mapped from the original Bloch spherical surface to half of its major axis. An ellipsoidal surface with and 1, such as Figure 2 As shown in (b). Based on this, the associated parameter can be rewritten as:

[0060] (6);

[0061] when , , , , At that time, the correlation function Take the maximum value, expressed as:

[0062] (7);

[0063] As can be seen from equation (7), the maximum correlation parameter value is equivalent to the length of the broken line path formed by sequentially connecting the endpoints of 2n+1 measurement vectors on the ellipsoidal surface, where the path segment connecting the centrally symmetric endpoints... The path length is not included.

[0064] Therefore, in this embodiment, the problem of maximizing the even-numbered chain CHSH associated parameters is transformed into: on the ellipsoidal surface, based on the central symmetry constraint relationship, finding a set of end points of the polyline path such that the effective length of the polyline path is maximized.

[0065] In a specific embodiment, to obtain the optimal measurement device configuration corresponding to the even chain CHSH correlation parameter, a parameter optimization method based on group search is used to maximize the length of the broken line path. In this embodiment, a genetic algorithm is used as an example to explain the configuration obtaining method. Specifically, the positions of the 2n endpoints in the broken line path, except for the center-symmetric constraint endpoints, are taken as independent configuration parameters, and a candidate configuration set is generated within a predetermined parameter range; the corresponding broken line path is constructed according to the center-symmetric constraint relationship, and the sum of the lengths of the path segments between the adjacent endpoints, except for the path segment connecting the center-symmetric endpoints, is calculated as the evaluation index of the candidate configuration.

[0066] On this basis, the candidate configuration group is iteratively updated through selection, recombination, and parameter perturbation updating operations, so that the candidate configurations with larger path lengths are retained or enhanced in subsequent iterations. The above process is repeated until a predetermined number of iterations or a convergence condition is met.

[0067] When the path length reaches the maximum, the corresponding configuration parameters are the configuration scheme for realizing the optimal measurement of the even chain CHSH correlation parameter.

[0068] It should be noted that the present application does not limit the use of the above genetic algorithm for solving, and other parameter optimization methods based on iterative search or heuristic optimization can also be used to realize the configuration obtaining method without departing from the technical idea of the present application.

[0069] The even chain CHSH correlation parameter optimal measurement configuration based on ellipsoid geometry optimization in this embodiment is further described below in combination with specific mathematical expressions and implementation steps.

[0070] Construction of the degree of concurrency of the non-maximal entangled state and the correlation matrix:

[0071] The measurement method of this embodiment is applicable to a two-dimensional two-particle pure state system. Taking a photon system as an example, a two-photon orbital angular momentum entangled state prepared by a spontaneous parametric down-conversion process can be expressed as: A two-dimensional subspace in the system is selected , and the entangled state is expressed as:

[0072] (10) ;

[0073] wherein the parameters satisfy the normalization condition For the measurement of the orbital angular momentum entangled state, such as Figure 3As shown, the target state to be measured is usually converted into a fundamental mode Gaussian light beam by setting a spatial light modulator (SLM), and the light beam is coupled into a single-mode optical fiber. For other modes that are not converted into the fundamental mode Gaussian light beam by the spatial light modulator, the projection measurement of specific modes is realized because they cannot be coupled into the single-mode optical fiber.

[0074] In the measurement process, photons A and B are introduced into the measurement module respectively, and coincidence measurement is performed on the signals output by the two single-mode optical fibers, so that the parameters and are obtained. Specifically, the parameters and are determined by the following relationship: wherein, represents the coincidence count of the measurement of the projection of the A photon to the state and the projection of the B particle to the state represents the coincidence count of the measurement of the projection of the A particle to the state and the projection of the B particle to the state . According to equation (4), the degree of entanglement of the entangled state can be calculated:

[0075] (11);

[0076] The correlation matrix K is defined in a diagonal form: which compresses the Bloch sphere into an ellipsoidal surface with the principal axis , representing the measurement direction space of the B particle.

[0077] Example of iterative search for the maximum measurement value:

[0078] In this embodiment, the broken line path corresponding to the 6-chain measurement structure contains 7 end points. The positions of the remaining 6 end points in the broken line path except for one of the central symmetric end points are taken as independent configuration parameters, and the position of the remaining one end point is determined according to the central symmetric constraint relationship.

[0079] Based on the independent configuration parameters, the broken line path is constructed, and the sum of the path segment lengths between adjacent end points in the broken line path is taken as the evaluation index of the correlation parameter. In order to obtain the maximum value of the evaluation index, an optimization method based on group search is used in this embodiment to iteratively search for the independent configuration parameters. Specifically, the independent configuration parameters can be encoded into candidate configuration individuals, and through fitness evaluation, configuration updating and iterative optimization, the evaluation index is gradually increased until the predetermined termination condition is met.

[0080] ​​By the above manner, the corresponding measurement device configuration when the broken line path length is maximized can be obtained, so that the optimal measurement of the even chain CHSH correlation parameter is realized. In the embodiment, the population search optimization method is realized by taking the genetic algorithm as an example, but the application is not limited to this specific algorithm form.

[0081] For example, assuming that the coincidence count measured by the experimental system is , the multiplicity can be calculated according to formula (11) 0.8, and the corresponding entangled state is constructed, which is represented as:

[0082] (12) ;

[0083] The maximum value of 10.8 (classical value ≤ 10) of the genetic algorithm is obtained (the value of 2n in the embodiment is 6), and the corresponding measurement vector is the optimal measurement scheme. It is known from the literature [Advanced Photonics Research, 2025, : 2500105] that the optimal measurement vector is located in the same plane containing the Z axis, so the maximum broken line path is located on the intersection ellipse of the ellipsoid and the plane , as shown in (a) of Figure 4 . In a special case, the optimal measurement configuration in the plane is selected, as shown in (b) of Figure 4 , and the specific measurement vector is as follows: . The measurement vector is reflected to the orbital angular momentum measurement state, and the optimal measurement state is:

[0084] (13) ;

[0085] According to the above measurement state configuration, the experimenter can directly set the corresponding measurement mode on the spatial light modulator as shown in Figure 3 , and perform joint projection measurement on particles A and B, and sum the expected values in the correlation function to complete the measurement of the even chain CHSH correlation parameter.

[0086] As shown in Figure 5 , the application also discloses a configuration acquisition system of an even setting CHSH measurement device with maximum violation, comprising:

[0087] The correlation parameter acquisition module 501 is configured to acquire quantum state information of a pair of two-dimensional non-maximal entangled particles A and B, and determine a correlation parameter representing an entanglement degree based on the quantum state information.

[0088] The space mapping module 502 is configured to construct a correlation mapping relationship according to the correlation parameter, and map a measurement direction parameter of the particle B from a Bloch sphere space to an ellipsoid surface by using the correlation mapping relationship.

[0089] The broken line path construction module 503 is configured to take 2n+1 points on the ellipsoid surface in the same plane as end points, the end points including an end point pair formed by two end points in a center symmetric relationship with respect to an ellipsoid center of the ellipsoid surface, and sequentially connect all the end points to obtain a broken line path including 2n line segments, with one end point of the end point pair as a starting point and the other end point of the end point pair as an ending point, the length formula of the broken line path being equivalent to a 2n-setting CHSH inequality correlation function maximum value formula of the particles A and B.

[0090] The iteration module 504 is configured to take any end point in the end point pair and other end points to form 2n end points, and perform iterative search on positions of the 2n end points with the length of the broken line path as a target function to obtain a maximum value of the length of the broken line path, and the corresponding correlation function maximum value formula reaches the maximum value.

[0091] The measurement configuration acquisition module 505 is configured to map the corresponding end point positions when the maximum value of the length of the broken line path is obtained into a measurement direction configuration of the particles A and B.

[0092] The measurement module 506 is configured to set a quantum measurement device according to the measurement direction configuration, and perform joint measurement on the particles A and B to obtain a measurement value for verifying quantum violation behavior of a 2n-setting CHSH inequality.

[0093] The specific implementation of the configuration acquisition system for realizing the maximum violation even-setting CHSH measurement device is the same as that of the configuration acquisition method for realizing the maximum violation even-setting CHSH measurement device, and the embodiment will not be repeated.

[0094] The above is only a specific implementation of the present application, but the design concept of the present application is not limited thereto, and any non-essential modification of the present application by using the concept should be regarded as an infringement of the protection scope of the present application.

Claims

1. A method for obtaining the configuration of a CHSH measurement device that achieves maximum even-number violation settings, characterized in that, Includes the following steps: S1, obtain the quantum state information of a pair of two-dimensional non-maximally entangled particles A and B, and determine the correlation parameters characterizing the degree of entanglement based on the quantum state information; S2, construct an association mapping relationship based on the association parameters, and use the association mapping relationship to map the measurement direction parameters of particle B from Bloch sphere space to an ellipsoidal surface; S3, taking 2n+1 points on the ellipsoidal surface that lie in the same plane as endpoints; the endpoints include pairs of endpoints formed by two endpoints that are centrally symmetric about the center of the ellipsoidal surface; taking one endpoint of the endpoint pair as the starting point and the other endpoint of the endpoint pair as the ending point, connecting all endpoints in sequence to obtain a broken line path including 2n line segments; the formula for the length of the broken line path is equivalent to the formula for the maximum value of the CHSH inequality correlation function of particle A and particle B with 2n settings; S4, take any one endpoint from the endpoint pair and combine it with other endpoints to form 2n endpoints; The positions of the 2n endpoints are iteratively searched using the length of the polyline path as the objective function to obtain the maximum value of the length of the polyline path; the maximum value of the corresponding correlation function is obtained. S5, when the maximum length of the broken line path is obtained, the corresponding endpoint position is mapped to the measurement direction configuration of particle A and particle B; S6, configure a quantum measurement device according to the measurement direction, perform joint measurement on particle A and particle B, and obtain the measurement value used to verify the quantum violation behavior of the 2n-set CHSH inequality.

2. The method for obtaining the configuration of the CHSH measurement device for achieving maximum even-number violation as described in claim 1, characterized in that, The correlation parameter is the concurrency level; the concurrency level is calculated based on the probability amplitude.

3. The method for obtaining the configuration of the CHSH measurement device for achieving maximum even-number violation as described in claim 2, characterized in that, The association mapping relationship is an association matrix in diagonal matrix form; the diagonal elements of the diagonal matrix are respectively , and -1; where, Indicates the degree of concurrency.

4. The method for obtaining the configuration of the CHSH measurement device for achieving maximum even-number violation as described in claim 1, characterized in that, The mapping of the endpoint positions corresponding to the maximum length of the broken path to the measurement direction configuration of particle A and particle B is specifically as follows: the measurement direction of particle B is determined by the vector pointing from the center of the ellipsoid to each endpoint of the broken path, and the measurement direction of particle A is determined by the direction of the line connecting adjacent endpoints in the broken path.

5. The method for obtaining the configuration of the CHSH measurement device for achieving maximum even-number violation as described in claim 1, characterized in that, The CHSH inequality correlation function for particles A and B, set at 2n, is expressed as follows: ； when ; in, This represents the measurement vectors of 2n selected points on the ellipsoidal surface; Indicates the association mapping relationship; Indicates the definition symbol; This represents the measurement vectors of the 2n points selected on the ellipsoid in the Bloch sphere of particle B; This represents the corresponding measurement vector in the Bloch sphere of particle A; Indicates an association function; This represents the measurement vector on the ellipsoidal surface of the endpoint that forms an endpoint pair with the 2nth endpoint.

6. The method for obtaining the configuration of the CHSH measurement device for achieving maximum even-number violation as described in claim 5, characterized in that, The measurement vector of particle A is represented as follows: ， ， ， ， ； in, This indicates taking the modulus.

7. The method for obtaining the configuration of the CHSH measurement device for achieving maximum even-number violation as described in claim 5, characterized in that, The formula for maximizing the CHSH inequality correlation function with setting 2n is expressed as follows: ； in, This represents the maximum value of the correlation function; This indicates taking the modulus.

8. The method for obtaining the configuration of the CHSH measurement device for achieving maximum even-number violation as described in claim 1, characterized in that, The principal axis of the ellipsoidal surface is aligned with a preset reference axis; when the maximum length of the polyline path is obtained, the corresponding endpoint is located on the elliptic curve formed by the intersection of the ellipsoidal surface and the plane containing the preset reference axis.

9. A configuration acquisition system for a CHSH measurement device that realizes the maximum even-number violation setting, characterized in that, Including the following: The correlation parameter acquisition module is used to acquire the quantum state information of a pair of two-dimensional non-maximally entangled particles A and B, and determine the correlation parameters characterizing the degree of entanglement based on the quantum state information. The spatial mapping module is used to construct an association mapping relationship based on the association parameters, and to use the association mapping relationship to map the measurement direction parameters of particle B from the Bloch sphere space to an ellipsoidal surface. The polyline path construction module is used to construct a polyline path with 2n+1 points on the same plane on the ellipsoidal surface as endpoints. The endpoints include pairs of endpoints formed by two endpoints that are centrally symmetric about the center of the ellipsoidal surface. Starting from one endpoint of the endpoint pair and ending at the other endpoint, all endpoints are connected sequentially to obtain a polyline path consisting of 2n line segments. The length formula of the constructed polyline path is equivalent to the maximum value formula of the CHSH inequality correlation function for particles A and B with 2n points. The iteration module is used to take any endpoint in an endpoint pair and form 2n endpoints with other endpoints; The positions of the 2n endpoints are iteratively searched using the length of the polyline path as the objective function to obtain the maximum value of the length of the polyline path; the maximum value of the corresponding correlation function is obtained. The measurement configuration acquisition module is used to map the corresponding endpoint positions when the maximum length of the polyline path is obtained to the measurement direction configurations of particle A and particle B; The measurement module is configured to set up a quantum measurement device according to the measurement direction, and to perform joint measurement on particle A and particle B to obtain measurement values ​​for verifying the quantum violation behavior of the 2n-set CHSH inequality.

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