Method and system for obtaining configuration of a maximum violation odd setting chsh measurement device

Abstract

The application discloses a configuration acquisition method and system of a maximum violation even setting CHSH measuring device, relates to the field of quantum information processing, and obtains quantum state information of two-dimensional non-maximum entangled particles A and B and calculates correlation parameters; correlation mapping is constructed, particle B measurement direction parameters are mapped from a Bloch sphere space to an ellipsoid surface; 2n+1 end points including a center symmetric end point pair in the same plane of the ellipsoid surface are connected into 2n line segments, and the length formula of the broken line path is equivalent to the maximum value formula of the 2n setting CHSH correlation function; the maximum broken line path length is searched iteratively by taking 2n end points, and the maximum value of the correlation function is taken; the optimal end point position is mapped as the measurement direction configuration of the particles A and B, the measuring device is set and measured, and the measurement value of verifying the quantum violation of the CHSH inequality is obtained. The application converts the maximum value problem of the even setting CHSH correlation function into the solving problem of the maximum value of the broken line path length, and the optimal measurement scheme is obtained through simple numerical fitting.

Description

Technical Field

[0001] This invention relates to the field of quantum information processing technology, and in particular to a method and system for acquiring the configuration of a CHSH measurement device that achieves the maximum violation of even numbers. Background Technology

[0002] In quantum information processing and quantum communication systems, the configuration of measurement devices directly affects the evaluation results of the correlation characteristics of particle systems. Under multiple measurement setups, it is usually necessary to rationally configure multiple measurement directions to obtain measurement results that meet specific correlation evaluation indicators. Among them, even-numbered chain measurement structures have attracted attention due to their high correlation evaluation sensitivity as the number of measurement setups increases.

[0003] Under ideal conditions, when a particle system is in a highly entangled state, the configuration of the measurement device typically exhibits a well-defined symmetry, and the selection of relevant parameters is relatively simple. However, in practical applications, due to factors such as quantum state preparation errors, transmission losses, and environmental disturbances, the particle system is often in a non-maximally entangled state. Under these conditions, the relationship between the measurement device configuration and the associated parameters becomes significantly more complex, and the optimal selection of the measurement direction parameters cannot be obtained through simple symmetry analysis.

[0004] For even-chain measurement structures under non-maximally entangled state conditions, existing technologies mostly employ analytical derivation or numerical simulation to calculate and optimize the associated parameters. For example, by scanning multiple measurement direction parameters point by point, the corresponding associated parameter values ​​are calculated, and a better configuration scheme is selected. However, as the number of measurement settings increases, the dimension of the parameter space that needs to be traversed increases rapidly, and the computational complexity increases significantly, making it difficult to obtain the globally optimal measurement device configuration under limited computational resources.

[0005] Furthermore, existing methods typically search for measurement directions directly in a high-dimensional parameter space, failing to fully utilize the implicit geometric constraints between measurement parameters. This results in a large amount of redundant computation during the search process and low configuration acquisition efficiency. Simultaneously, existing technologies lack a unified, structured framework for configuration acquisition, making it difficult to transform the optimization problem of correlated parameters under arbitrary even-numbered chain measurement structures into a computationally feasible process, thus limiting the application of such measurement structures in practical quantum information systems.

[0006] The experimental measurement process for even-chained CHSH correlation parameters is described as follows: The expression for even-chained CHSH correlation parameters is given:

[0007] (1);

[0008] If the correlation parameter is measured experimentally The value is greater than This proves the nonlocality of the system. In the actual experimental verification, the expectation function in equation (1) It can be obtained through coincidence counting, and is expressed as:

[0009] (2);

[0010] coincidence count To project particle A onto the state Simultaneously projecting the B particle onto the state The joint measurement count. Among them, the two-dimensional particle state , It can be represented as:

[0011] (3).

[0012] Therefore, there is an urgent need for a method for acquiring the configuration of measurement devices for even-numbered chain measurement structures under non-maximum entanglement conditions. This method should be able to effectively reduce the dimensionality of parameter search based on clearly defined measurement parameter constraints, transforming the optimization problem of associated parameters into a computational process that is structurally clear and easy to implement, thereby improving the efficiency and practicality of acquiring the configuration of measurement devices. Summary of the Invention

[0013] To address the above problems, this invention proposes a method and system for acquiring the configuration of a measurement device with maximum even-numbered CHSH settings. By using geometric mapping, the optimization problem of CHSH correlation parameters with even-numbered settings is transformed into an optimization problem of geometric path length. Through a structured parameter search process, the optimal measurement device configuration suitable for non-maximum entangled states is efficiently acquired, thereby reducing the configuration search complexity and improving the feasibility of the measurement device in practical quantum information processing systems.

[0014] On the one hand, the method for obtaining the configuration of the CHSH measurement device with the maximum even number violation setting is as follows:

[0015] 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;

[0016] 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;

[0017] 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;

[0018] S4, take any endpoint from the endpoint pair and form 2n endpoints with other endpoints; use the length of the polyline path as the objective function to iteratively search the positions of the 2n endpoints to obtain the maximum value of the length of the polyline path; obtain the maximum value of the corresponding correlation function formula;

[0019] 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;

[0020] 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.

[0021] Preferably, the correlation parameter is the concurrency degree; the concurrency degree is calculated based on the probability amplitude.

[0022] Preferably, 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.

[0023] Preferably, 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.

[0024] Preferably, the 2n-set CHSH inequality correlation function for particles A and B is expressed as:

[0025] ;

[0026] when ;

[0027] 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.

[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 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.

[0039] The iterative module is used to take any endpoint in the endpoint pair and form 2n endpoints with other endpoints; iteratively search the positions of the 2n endpoints with 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.

[0040] 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;

[0041] 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.

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

[0043] (1) This invention transforms the optimization problem of even-numbered chain CHSH associated parameters into the optimization problem of the path length of a broken line in an ellipsoidal surface, so that the originally complex parameter optimization process has a clear geometric structure, which is convenient for engineering implementation and algorithm design.

[0044] (2) This invention proposes a unified method for obtaining measurement configuration under non-maximally entangled state conditions, which does not depend on specific symmetry assumptions and has good versatility;

[0045] (3) The present invention uses an iterative search method to optimize the configuration parameters, without limiting the specific optimization algorithm form. It is applicable to various parameter search and optimization implementation methods and has good scalability.

[0046] (4) The measurement device configuration acquisition method provided by the present invention can be directly applied to quantum communication, quantum measurement and related information processing systems. It has high engineering application value and is conducive to improving the device configuration efficiency under multiple measurement settings. Attached Figure Description

[0047] The present invention will now be described in further detail with reference to the accompanying drawings;

[0048] Figure 1This is a flowchart illustrating the method for obtaining the configuration of the CHSH measurement device for setting the maximum even number of violations, 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 one specific embodiment, to obtain the optimal measurement device configuration corresponding to the even-numbered chain CHSH correlation parameters, a parameter optimization method based on population search can be used to maximize the length of the polyline path. This embodiment uses a genetic algorithm as an example to illustrate the configuration acquisition method. Specifically, the 2n endpoint positions in the polyline path, excluding the endpoints of the central symmetry constraint, are used as independent configuration parameters, and a candidate configuration set is generated within a predetermined parameter range. A corresponding polyline path is constructed based on the central symmetry constraint relationship, and the sum of the path segment lengths between adjacent endpoints, excluding the path segment connecting the central symmetry endpoints, is calculated as an evaluation index for the candidate configuration.

[0066] Based on this, the candidate configuration group is iteratively updated through selection, recombination, and parameter perturbation operations, ensuring that candidate configurations with longer path lengths are retained or enhanced in subsequent iterations. This process is repeated until the predetermined number of iterations or convergence criteria are met.

[0067] When the path length reaches its maximum, the corresponding configuration parameters are the configuration scheme for achieving the optimal measurement device for even-numbered chain CHSH correlation parameters.

[0068] It should be noted that the present invention is not limited to using the above-mentioned genetic algorithm for solving the problem. Other parameter optimization methods based on iterative search or heuristic optimization can also be used to implement the configuration acquisition method without departing from the technical concept of the present invention.

[0069] The following section, combining specific mathematical expressions and implementation steps, further explains the optimal measurement configuration of even-numbered CHSH correlation parameters based on ellipsoidal geometry optimization in this embodiment.

[0070] Construction of concurrency degree and correlation matrix for non-maximally entangled states:

[0071] The measurement method in this embodiment is applicable to two-dimensional two-particle pure-state systems. Taking a photonic system as an example, the two-photon orbital angular momentum entangled state prepared by a spontaneous parametric downconversion process can be expressed as: Select a two-dimensional subspace in the system. Its entangled state is represented as:

[0072] (10);

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

[0074] During the measurement process, photon A and photon B are introduced into the measurement module respectively, and the coincidence measurement of the signals output from the two single-mode fibers is performed to obtain the parameters. and Specifically, the parameters and This is determined through the following relationship: ,in, This indicates that the projection of photon A onto the state was measured. Simultaneously, the B particle is projected onto the state. The coincidence count; This indicates that the projection of particle A onto the state is measured. Simultaneously, the B particle is projected onto the state. The coincidence count. According to equation (4), the concurrency degree of the entangled state can be calculated:

[0075] (11);

[0076] The incidence matrix K is defined in diagonal form: This matrix compresses the Bloch sphere into a principal axis. The ellipsoid represents the measurement direction space of the B particle.

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

[0078] In this embodiment, the polygonal path corresponding to the 6-chain measurement structure is considered to have 7 endpoints. The positions of the remaining 6 endpoints of the polygonal path, excluding one of the centrally symmetric endpoints, are used as independent configuration parameters, and the position of the remaining endpoint is determined according to the central symmetry constraint relationship.

[0079] A polyline path is constructed based on the independent configuration parameters, and the sum of the path segment lengths between adjacent endpoints in the polyline path is used as the evaluation index of the association parameter. To obtain the maximum value of the evaluation index, this embodiment employs a population search-based optimization method to iteratively search the independent configuration parameters. Specifically, the independent configuration parameters can be encoded as candidate configuration individuals, and through fitness evaluation, configuration updates, and iterative optimization, the evaluation index is gradually increased until a predetermined termination condition is met.

[0080] By employing the above method, the measurement device configuration corresponding to maximizing the length of the polyline path can be obtained, thereby achieving the optimal measurement of the even-numbered chain CHSH correlation parameter. In this embodiment, the population search optimization method is implemented using a genetic algorithm as an example, but the present invention is not limited to this specific algorithm form.

[0081] Example, assuming the coincidence count measured by the experimental system According to equation (11), the concurrency can be calculated as follows: 0.8, construct the corresponding entangled state, represented as:

[0082] (12);

[0083] Obtained through genetic algorithm (In this embodiment, 2n is taken as 6) The maximum value is 10.8 (classical value ≤ 10), and the corresponding measurement vector is the optimal measurement scheme. According to the literature [Advanced Photonics Research, 2025, :2500105], the optimal measurement vector lies in the same plane containing the Z-axis; therefore, the maximum broken line path lies between the ellipsoid and this plane ( On the intersection of the ellipse (face), such as Figure 4 As shown in (a). Specifically, selected in The optimal measurement configuration for the surface, such as Figure 4 As shown in (b), the specific measurement vector is as follows: By mapping the measurement vector back to the orbital angular momentum measurement state, the optimal measurement state can be obtained as follows:

[0084] (13);

[0085] Based on the above measurement state configuration, the experimenter can directly perform the following: Figure 3 The corresponding measurement mode is set on the spatial light modulator shown, and joint projection measurement is performed on particle A and particle B. The expected values ​​of each term in the correlation function are statistically obtained and summed to complete the measurement of the even-numbered chain CHSH correlation parameters.

[0086] like Figure 5 As shown, the present invention also discloses a configuration acquisition system for implementing a CHSH measurement device for maximum violation of even numbers, comprising:

[0087] The correlation parameter acquisition module 501 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.

[0088] The spatial mapping module 502 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.

[0089] The polyline path construction module 503 is used to take 2n+1 points on the ellipsoidal surface located 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 polyline path including 2n line segments; the length formula of the polyline path is equivalent to the maximum value formula of the 2n-set CHSH inequality correlation function for particles A and B;

[0090] The iteration module 504 is used to take any endpoint in the endpoint pair and form 2n endpoints with other endpoints; iterate and search the positions of the 2n endpoints with the length of the polyline path as the objective function to obtain the maximum value of the length of the polyline path; and obtain the maximum value of the corresponding correlation function maximum value formula.

[0091] The measurement configuration acquisition module 505 is used to map the corresponding endpoint positions when the maximum length of the polyline path is obtained to the measurement direction configuration of particle A and particle B.

[0092] Measurement module 506 is configured to set up a quantum measurement device according to the measurement direction, and 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.

[0093] The specific implementation of the configuration acquisition system for the CHSH measurement device with the maximum even number violation setting is the same as the configuration acquisition method for the CHSH measurement device with the maximum even number violation setting, and will not be described again in this embodiment.

[0094] The above are merely specific embodiments of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial modifications made to the present invention using this concept shall be considered as infringing upon the protection scope of the present invention.

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, map the endpoint positions corresponding to the maximum length of the broken line path to the measurement direction configuration of particle A and particle B; S6, configure the 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; 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; 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.

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 measurement vector of particle A is represented as: ， ， ， ， ； in, This indicates taking the modulus.

6. 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.

7. A configuration acquisition system for a CHSH measurement device that realizes the maximum violation of even number settings, 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 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. 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 perform joint measurement on particle A and particle B to obtain the measurement value used to verify the quantum violation behavior of the 2n-set CHSH inequality. 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; 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.

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