Quantum state preparation method and readout system based on coherent light source

Abstract

The invention discloses a quantum state preparation method and a readout system based on a coherent light source, and the method comprises the steps: extracting physical parameters related to the phase and frequency of photons and interference information of an external environment, and carrying out the data preprocessing through combining noise filtering and dimensionless processing. A quantum neural network optimization model is utilized, a steady-state retention coefficient Ssc and a preparation environment suitability coefficient Cenv are combined for fitting to obtain a phase stability index Pst of preparation photons, a phase stability threshold L is set, and environmental noise interference is evaluated by calculating a phase instability rate Pun; if the control range is exceeded, an adjusting instruction is sent out in time; the method effectively solves the problems that the quantum state is susceptible to noise interference and the preparation accuracy and stability are difficult to guarantee, and improves the reliability of quantum state preparation.

Description

Technical Field

[0001] The present invention relates to the field of quantum communication technology, and in particular to a quantum state preparation method and a readout system based on a coherent light source. Background Art

[0002] Quantum state preparation originated from the basic research of quantum mechanics, especially the introduction of quantum superposition principle and entangled state in the 1920s. With the development of quantum computing and quantum communication, quantum state preparation technology has been gradually improved. At the end of the 20th century, quantum state preparation was widely used in photon, superconductor, ion trap and other systems, and became one of the core technologies for realizing quantum information processing, promoting the rapid progress in the field of quantum technology.

[0003] In the field of quantum communication technology, although quantum state preparation is an important step in realizing quantum communication, there are still some technical shortcomings, as follows:

[0004] 1. Quantum states are easily affected by environmental noise: Quantum states are easily affected by environmental noise during transmission, including thermal noise, electromagnetic interference, etc. These noises can cause the decoherence effect of quantum states, causing the original quantum states to deviate or decay, thereby affecting the reliability and accuracy of quantum communication. This is particularly evident in long-distance communications, resulting in reduced transmission efficiency of entangled states or single photons.

[0005] 2. The accuracy and stability of quantum state preparation are difficult to guarantee: During the preparation of quantum states, the system must be controlled with high precision. However, due to the limitations of experimental conditions, equipment accuracy, and external uncertainties, it is often difficult to achieve the desired accuracy in the preparation of quantum states. This instability may lead to problems such as erroneous transmission and decoding difficulties in the communication system, thus affecting the overall communication efficiency. Summary of the invention

[0006] The purpose of the present invention is to provide a quantum state preparation method and a readout system based on a coherent light source to solve the above problems.

[0007] The present invention is achieved through the following technical solutions:

[0008] The method for preparing a quantum state based on a coherent light source comprises the following steps:

[0009] S1. Extract the physical parameters related to the phase and frequency of photons from the coherent light source system in advance and construct an initial photon state data set; then track and record the noise level and temperature changes of the external environment, and finally construct an interference information data set;

[0010] S2, performing data preprocessing on the initial photon state data set and the interference information data set obtained in step S1, including noise filtering and parameter dimensionless processing; then, extracting relevant noise model information prepared by the corresponding quantum state according to the interference information data set;

[0011] S3, extract the initial photon state data set and the interference information data set after preprocessing for calculation, and obtain the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph respectively; obtain and evaluate the steady-state maintenance coefficient Ssc in the preparation process by associating the coherence maintenance time Tco with the interference noise level Nno; according to the evaluation content of the steady-state maintenance coefficient Ssc, fit the ambient temperature change value Thb and the number of photons Nph to further calculate and evaluate the current preparation environment suitability coefficient Cenv and evaluate it; finally, combine the quantum neural network with the relevant noise model information to construct a quantum state preparation optimization model and after training, fit the steady-state maintenance coefficient Ssc with the preparation environment suitability coefficient Cenv through the quantum state preparation optimization model to obtain the phase stability index Pst of the prepared photons;

[0012] S4. Compare the preset phase stability threshold L with the phase stability index Pst to obtain the phase instability rate Pun. By comparing and evaluating the phase instability rate Pun with the phase stability threshold L, and comprehensively judging whether the environmental noise interference in the current quantum state preparation process is within the controllable range based on the evaluation content of the phase instability rate Pun, if it is not within the controllable range, issue a preparation adjustment instruction to the outside and take corresponding adjustment measures.

[0013] Preferably,

[0014] S11, the physical parameters related to the phase and frequency of photons are respectively obtained by monitoring and recording through the phase detection device, the spectrometer and the photon detector; wherein the initial photon state data set includes the phase jitter amplitude Gxd, the photon frequency deviation Gpc, the phase noise spectral density Gxw, the photon emission rate Gfs, the photon detection efficiency Gjc and the attenuation coefficient Gsj;

[0015] S12, the noise level and temperature change of the external environment are collected and obtained by the environmental noise sensor, spectrum analyzer and temperature sensor respectively; wherein the interference information data set includes the environmental background noise intensity Hbj, the electronic noise intensity Hnb inside the device, the optical noise intensity Hgz, the instantaneous temperature Hsw, the temperature change rate Hwb and the internal temperature Hsb of the device;

[0016] Preferably,

[0017] S21, performing noise filtering and outlier processing on the initial photon state data set and the interference information data set, wherein the noise filtering includes removing environmental noise by a low-pass filter or a Kalman filter, and the outlier processing includes correcting sudden abnormal data by an interpolation method or a mean compensation method;

[0018] S22. Perform dimensionless processing on the preprocessed data to eliminate the dimensional differences between different physical quantities, and perform data extraction for analyzing the influence of noise interference in the quantum state preparation process based on the dimensionless interference information data set.

[0019] Preferably,

[0020] S31, extracting the initial photon state data set and the interference information data set, and calculating the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the photon number Nph by the following formulas respectively:

[0021]

[0022] Nno=Hbj+Hnb+Hgz;

[0023]

[0024] Nph = Gfs × Gjc × (1-Gsj);

[0025] Where t represents the time interval.

[0026] Preferably,

[0027] S32, the specific calculation and evaluation contents of the steady-state retention coefficient Ssc are as follows:

[0028]

[0029] By presetting the steady-state holding threshold Q and comparing it with the steady-state holding coefficient Ssc, the following evaluation content is generated:

[0030] When the steady-state maintenance coefficient Ssc ≥ the steady-state maintenance threshold Q, it means that the coherence and steady-state maintenance capabilities in the quantum state preparation process are in compliance. At this time, no additional adjustment is required and the current preparation environment should continue to be evaluated.

[0031] When the steady-state maintenance coefficient Ssc is less than the steady-state maintenance threshold Q, it means that the coherence and steady-state maintenance ability in the quantum state preparation process do not meet the tolerable range of the system. At this time, adjustment measures need to be taken, including adding a shielding layer, improving the noise filtering algorithm, and adjusting the environmental control until the steady-state maintenance coefficient Ssc meets the tolerable range of the system.

[0032] Preferably,

[0033] S33, extracting the ambient temperature change value Thb and the number of photons Nph and calculating the preparation environment suitability coefficient Cenv using the following formula:

[0034]

[0035] The evaluation is performed by presetting the environmental suitability threshold W and the preparation environmental suitability coefficient Cenv. The specific evaluation contents are as follows:

[0036] When the preparation environment suitability coefficient Cenv ≥ the environmental suitability threshold W, it indicates that the current preparation environment is suitable for quantum state preparation; no additional adjustment is required.

[0037] When the preparation environment suitability coefficient Cenv is less than the environmental suitability threshold W, it indicates that the current preparation environment is not suitable for quantum state preparation; the specific reasons include excessive temperature changes or insufficient number of photons; at this time, measures are taken to make adjustments, including adjusting the ambient temperature, reducing interference and increasing the photon emission rate.

[0038] Preferably,

[0039] S34. The specific calculation formula for the phase stability index Pst of the prepared photons is:

[0040] Pst=α·SsC+β·Cenv;

[0041] In the formula, α represents the weight value of the steady-state maintenance coefficient Ssc, β represents the weight value of the preparation environment suitability coefficient Cenv; and α+β=1, 0<α≤1, 0<β≤1.

[0042] Preferably,

[0043] S41, the specific formula for obtaining the phase instability rate Pun is as follows:

[0044]

[0045] Preferably,

[0046] S42. By comparing the phase instability rate Pun with the phase stability threshold L, the environmental noise interference in the current quantum state preparation process is evaluated, and a comprehensive judgment is made as to whether the noise is within a controllable range. The specific evaluation content is:

[0047] If the phase instability rate Pun ≤ the phase stability threshold L, it means that the system noise interference is within the controllable range, the quantum state preparation process is stable, and no intervention is required;

[0048] If the phase instability rate Pun is greater than the phase stability threshold L, it means that the system noise interference is not within the controllable range. At this time, a preparation adjustment instruction is issued and corresponding adjustment measures are taken, including adjusting the physical environment of quantum state preparation, adjusting the noise source and system stability.

[0049] Preferably, the quantum state readout system based on a coherent light source, according to the quantum state preparation method based on a coherent light source according to any one of claims 1 to 9, comprises a data acquisition module, a data preprocessing module, a readout analysis module and a system control module;

[0050] The data acquisition module extracts physical parameters related to the phase and frequency of photons from the coherent light source system in advance to construct an initial photon state data set, and simultaneously tracks and records the noise level and temperature changes of the external environment to construct an interference information data set;

[0051] The data preprocessing module performs data preprocessing on the acquired initial photon state data set and interference information data set, including noise filtering and parameter dimensionless processing;

[0052] The readout analysis module performs feature extraction on the preprocessed initial photon state data set and the interference information data set to respectively obtain the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph; obtains and evaluates the steady-state maintenance coefficient Ssc in the preparation process by associating the coherence maintenance time Tco with the interference noise level Nno; according to the evaluation content of the steady-state maintenance coefficient Ssc, fits the ambient temperature change value Thb and the number of photons Nph to further calculate and evaluate the current preparation environment suitability coefficient Cenv and evaluates it; finally, the quantum neural network is combined with the relevant noise model information to construct a quantum state preparation optimization model and after training, the steady-state maintenance coefficient Ssc is fitted with the environmental suitability coefficient Cenv through the quantum state preparation optimization model to obtain the phase stability index Pst of the prepared photons;

[0053] The system control module pre-sets a phase stability threshold L, and obtains a phase instability rate Pun by comparing the phase stability index Pst of each photon. The phase instability rate Pun is compared and analyzed with the phase stability threshold L to comprehensively determine whether the environmental noise interference in the current quantum state readout process is within a controllable range. If it is not within the controllable range, a readout adjustment instruction is issued to the outside and corresponding adjustment measures are taken.

[0054] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0055] 1. The present invention constructs an initial photon state data set and an interference information data set by extracting physical parameters related to the phase and frequency of photons and interference information of the external environment, and uses noise filtering and parameter dimensionless processing to perform data preprocessing. Finally, the phase stability index Pst of the prepared photons is obtained by fitting the quantum neural network optimization model in combination with the steady-state retention coefficient Ssc and the preparation environment suitability coefficient Cenv; the optimization steps in these processes help solve the problem that the quantum state is easily disturbed by environmental noise, ensuring that the coherence of the quantum state can still be effectively maintained in a high-noise environment, thereby improving the preparation accuracy and stability of the quantum state;

[0056] 2. The present invention sets a phase stability threshold L for comparison with the phase stability index Pst, and calculates the phase instability rate Pun to evaluate whether the environmental noise exceeds the controllable range. If so, an adjustment instruction is issued in time. This method not only improves the dynamic adaptability to the ambient temperature change value Thb and the number of photons Nph during the quantum state preparation process, but also ensures the system's high-precision preparation capability under complex and changeable environmental conditions by evaluating the environmental suitability coefficient Cenv and the steady-state maintenance coefficient Ssc. It effectively solves the technical shortcomings of the difficulty in ensuring the accuracy and stability during the quantum state preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0058] Figure 1 It is a schematic flow chart of the steps of the quantum state preparation method based on coherent light source of the present invention;

[0059] Figure 2 It is a schematic diagram of the framework structure of the quantum state readout system based on coherent light source of the present invention. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and drawings. The schematic implementation modes and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention. It should be noted that the present invention is already in the actual development and use stage.

[0061] Example 1

[0062] like Figure 1 As shown, this embodiment includes a quantum state preparation method based on a coherent light source, characterized in that it includes the following steps:

[0063] S1. Extract the physical parameters related to the phase and frequency of photons from the coherent light source system in advance and construct an initial photon state data set; then track and record the noise level and temperature changes of the external environment, and finally construct an interference information data set;

[0064] S2, performing data preprocessing on the initial photon state data set and the interference information data set obtained in step S1, including noise filtering and parameter dimensionless processing; then, extracting relevant noise model information prepared by the corresponding quantum state according to the interference information data set;

[0065] S3, extract the pre-processed initial photon state data set and the interference information data set for calculation, and respectively obtain the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph; by correlating the coherence maintenance time Tco with the interference noise level Nno, obtain and evaluate the steady-state maintenance coefficient Ssc in the preparation process; then, according to the evaluation content of the steady-state maintenance coefficient Ssc, fit the ambient temperature change value Thb and the number of photons Nph to further calculate and evaluate the current preparation environment suitability coefficient Cenv; finally, combine the quantum neural network with the relevant noise model information to construct a quantum state preparation optimization model and after training, fit the steady-state maintenance coefficient Ssc with the preparation environment suitability coefficient Cenv through the quantum state preparation optimization model to obtain the phase stability index Pst of the prepared photons;

[0066] S4. Compare the preset phase stability threshold L with the phase stability index Pst to obtain the phase instability rate Pun. By comparing and evaluating the phase instability rate Pun with the phase stability threshold L, and comprehensively judging whether the environmental noise interference in the current quantum state preparation process is within the controllable range based on the evaluation content of the phase instability rate Pun, if it is not within the controllable range, issue a preparation adjustment instruction to the outside and take corresponding adjustment measures.

[0067] In this embodiment, step 1 extracts the physical parameters related to the phase and frequency of the photons and constructs an interference information data set, which is helpful to accurately record the photon state and environmental interference information; step 2 performs noise filtering and dimensionless parameter processing to extract the corresponding noise model information, which can effectively eliminate noise interference and unify the dimensional differences of physical parameters to ensure the accuracy and comparability of the data; step 3 first constructs the steady-state holding coefficient Ssc by calculating the coherence holding time Tco and the interference noise level Nno; then, when the steady-state holding coefficient Ssc reaches or exceeds the preset threshold, the ambient temperature change value Thb and the number of photons Nph are extracted to further construct the preparation environment suitability coefficient Cenv; when the preparation environment suitability coefficient Cenv also reaches the preset threshold, the steady-state holding coefficient Ssc and the environmental suitability coefficient Cenv are fitted to obtain the phase stability index Pst, which helps to optimize the environmental regulation and system stability in the quantum state preparation process; step 4 compares the phase stability index Pst with the preset phase stability threshold L to obtain the phase instability rate Pun, evaluate whether the environmental noise is within the controllable range, ensure the phase stability in the quantum state preparation process, and issue adjustment instructions when necessary to maintain the high precision and high stability of the system.

[0068] Example 2

[0069] S11, the physical parameters related to the phase and frequency of photons are respectively obtained by monitoring and recording through the phase detection device, the spectrometer and the photon detector; wherein the initial photon state data set includes the phase jitter amplitude Gxd, the photon frequency deviation Gpc, the phase noise spectral density Gxw, the photon emission rate Gfs, the photon detection efficiency Gjc and the attenuation coefficient Gsj;

[0070] S12, the noise level and temperature change of the external environment are collected and obtained by the environmental noise sensor, spectrum analyzer and temperature sensor respectively; wherein the interference information data set includes the environmental background noise intensity Hbj, the electronic noise intensity Hnb inside the device, the optical noise intensity Hgz, the instantaneous temperature Hsw, the temperature change rate Hwb and the internal temperature Hsb of the device;

[0071] In this embodiment, the phase detection device, spectrometer and photon detector in S11 are used to obtain physical parameters related to the phase and frequency of photons to form an initial photon state data set, including phase jitter amplitude Gxd, photon frequency deviation Gpc, phase noise spectral density Gxw, photon emission rate Gfs, photon detection efficiency Gjc and attenuation coefficient Gsj, ensuring high-precision recording of photon states; these parameters are used to measure the stability, frequency accuracy, signal-to-noise ratio and system efficiency of photons during transmission, respectively; S12 collects the noise level and temperature change of the external environment through an environmental noise sensor, a spectrum analyzer and a temperature sensor to form an interference information data set, including environmental background noise intensity Hbj, electronic noise intensity Hnb inside the device, optical noise intensity Hgz, instantaneous temperature Hsw, temperature change rate Hwb and internal temperature Hsb of the device. These parameters help to fully understand and quantify the impact of the external environment on quantum state preparation, ensuring the effectiveness of environmental control and the accuracy of regulation; by accurately collecting these parameters, the stability and accuracy of quantum state preparation can be optimized, the system's anti-interference ability can be improved, and the successful preparation of quantum states can be ensured.

[0072] Example 3

[0073] S21, performing noise filtering and outlier processing on the initial photon state data set and the interference information data set, wherein the noise filtering includes removing environmental noise by a low-pass filter or a Kalman filter, and the outlier processing includes correcting sudden abnormal data by an interpolation method or a mean compensation method;

[0074] S22. Perform dimensionless processing on the preprocessed data to eliminate the dimensional differences between different physical quantities, and perform data extraction for analyzing the influence of noise interference in the quantum state preparation process based on the dimensionless interference information data set.

[0075] In this embodiment, S21 is used to filter noise and process outliers on the initial photon state data set and the interference information data set, and a low-pass filter or a Kalman filter is used to remove environmental noise to ensure the purity and accuracy of the data. At the same time, the interpolation method or the mean compensation method is used to correct the sudden abnormal data, thereby effectively improving the continuity and reliability of the data; S22 is used to perform dimensionless processing on the preprocessed data, thereby eliminating the dimensional differences between different physical quantities, so that various data can be compared and calculated under a unified standard, and data extraction is performed based on the dimensionless interference information data set to analyze the influence of noise interference in the quantum state preparation process, thereby ensuring that the noise source identification in the quantum state preparation process is more accurate; these steps optimize the data quality and the accuracy of the analysis, improve the stability and noise resistance of the quantum state preparation process, and provide a better data foundation for subsequent quantum state optimization and control.

[0076] Example 4

[0077] S31, extracting the initial photon state data set and the interference information data set, and calculating the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the photon number Nph by the following formulas respectively:

[0078]

[0079] Nno=Hbj+Hnb+Hgz;

[0080]

[0081] Nph = Gfs × Gjc × (1-Gsj);

[0082] Where t represents the time interval.

[0083] S32, the specific calculation and evaluation contents of the steady-state retention coefficient Ssc are as follows:

[0084]

[0085] By presetting the steady-state holding threshold Q and comparing it with the steady-state holding coefficient Ssc, the following evaluation content is generated:

[0086] When the steady-state maintenance coefficient Ssc ≥ the steady-state maintenance threshold Q, it means that the coherence and steady-state maintenance capabilities in the quantum state preparation process are in compliance. At this time, no additional adjustment is required and the current preparation environment should continue to be evaluated.

[0087] When the steady-state maintenance coefficient Ssc is less than the steady-state maintenance threshold Q, it means that the coherence and steady-state maintenance ability in the quantum state preparation process do not meet the tolerable range of the system. At this time, adjustment measures need to be taken, including adding a shielding layer, improving the noise filtering algorithm, and adjusting the environmental control until the steady-state maintenance coefficient Ssc meets the tolerable range of the system.

[0088] S33, extracting the ambient temperature change value Thb and the number of photons Nph and calculating the preparation environment suitability coefficient Cenv using the following formula:

[0089]

[0090] The evaluation is performed by presetting the environmental suitability threshold W and the preparation environmental suitability coefficient Cenv. The specific evaluation contents are as follows:

[0091] When the preparation environment suitability coefficient Cenv ≥ the environmental suitability threshold W, it indicates that the current preparation environment is suitable for quantum state preparation; no additional adjustment is required.

[0092] When the preparation environment suitability coefficient Cenv is less than the environmental suitability threshold W, it indicates that the current preparation environment is not suitable for quantum state preparation; the specific reasons include excessive temperature changes or insufficient number of photons; at this time, measures are taken to make adjustments, including adjusting the ambient temperature, reducing interference and increasing the photon emission rate.

[0093] S34. The specific calculation formula for the phase stability index Pst of the prepared photons is:

[0094] Pst=α·SsC++β·CenV;

[0095] In the formula, α represents the weight value of the steady-state maintenance coefficient Ssc, β represents the weight value of the preparation environment suitability coefficient Cenv; and α+β=1, 0<α≤1, 0<β≤1.

[0096] In this embodiment, a series of steps are used to calculate and evaluate the key parameters in the quantum state preparation process, thereby optimizing the stability and environmental adaptability of the preparation process; S31 extracts the initial photon state data set and the interference information data set to calculate the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph, thereby ensuring the coherence and stability in the quantum state preparation process; S32 further compares the steady-state maintenance coefficient Ssc with the preset steady-state maintenance threshold Q. When the steady-state maintenance coefficient Ssc reaches or exceeds the steady-state maintenance threshold Q, it indicates that the system has good steady-state maintenance ability under noise interference, and then further calculates and evaluates the preparation environment suitability coefficient Cenv; and when the steady-state maintenance coefficient Ssc is less than the steady-state maintenance threshold Q, it is necessary to take adjustment measures such as shielding, filtering and environmental control. This step ensures the long-term stability of the quantum state;

[0097] S33 evaluates the impact of the ambient temperature change value Thb and the number of photons Nph on the preparation environment by calculating the preparation environment suitability coefficient Cenv. If the environmental suitability coefficient Cenv reaches or exceeds the environmental suitability threshold W, no adjustment is required. If it is insufficient, it indicates that the ambient temperature fluctuates or the number of photons is not suitable, and corresponding adjustments are required to ensure the adaptability of the preparation environment; S34 When both the steady-state maintenance coefficient Ssc and the environmental suitability coefficient Cenv reach the preset threshold, the steady-state maintenance coefficient Ssc is fitted with the preparation environment suitability coefficient Cenv again to obtain the phase stability index Pst, which reflects the phase stability of photons under the current environmental conditions and provides a key reference for maintaining high precision and phase stability in the quantum state preparation process.

[0098] Example 5

[0099] S41, the specific formula for obtaining the phase instability rate Pun is as follows:

[0100]

[0101] S42. By comparing the phase instability rate Pun with the phase stability threshold L, the environmental noise interference in the current quantum state preparation process is evaluated, and a comprehensive judgment is made as to whether the noise is within a controllable range. The specific evaluation content is:

[0102] If the phase instability rate Pun ≤ the phase stability threshold L, it means that the system noise interference is within the controllable range, the quantum state preparation process is stable, and no intervention is required;

[0103] If the phase instability rate Pun is greater than the phase stability threshold L, it means that the system noise interference is not within the controllable range. At this time, a preparation adjustment instruction is issued and corresponding adjustment measures are taken, including adjusting the physical environment of quantum state preparation, adjusting the noise source and system stability.

[0104] In this embodiment, by comparing the calculation of the phase instability rate Pun with the phase stability threshold L, the influence of environmental noise on the phase stability during the quantum state preparation process is effectively evaluated; S41 obtains the phase instability rate Pun through formula calculation, which reflects the phase stability of the system under the current environment; S42 compares and evaluates the phase instability rate Pun with the phase stability threshold L to determine whether the noise is within a controllable range. When Pun is less than or equal to L, it means that the system noise interference is small, the quantum state preparation process is stable, and no additional measures are needed. When Pun is greater than L, it indicates that the noise interference exceeds the controllable range. At this time, corresponding adjustment measures need to be taken, including optimizing the physical environment of quantum state preparation, adjusting the noise source or improving the stability of the system. This evaluation and adjustment mechanism can dynamically monitor and control noise interference, ensure the accuracy and phase stability of quantum state preparation, and effectively improve the overall performance and reliability of the system.

[0105] Example 6

[0106] like Figure 2 As shown, the quantum state readout system based on coherent light source includes a data acquisition module, a data preprocessing module, a readout analysis module and a system control module;

[0107] The data acquisition module extracts physical parameters related to the phase and frequency of photons from the coherent light source system in advance to construct an initial photon state data set, and simultaneously tracks and records the noise level and temperature changes of the external environment to construct an interference information data set;

[0108] The data preprocessing module performs data preprocessing on the acquired initial photon state data set and interference information data set, including noise filtering and parameter dimensionless processing;

[0109] The readout analysis module performs feature extraction on the preprocessed initial photon state data set and the interference information data set to respectively obtain the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph; obtains and evaluates the steady-state maintenance coefficient Ssc in the preparation process by associating the coherence maintenance time Tco with the interference noise level Nno; according to the evaluation content of the steady-state maintenance coefficient Ssc, fits the ambient temperature change value Thb and the number of photons Nph to further calculate and evaluate the current preparation environment suitability coefficient Cenv and evaluates it; finally, the quantum neural network is combined with the relevant noise model information to construct a quantum state preparation optimization model and after training, the steady-state maintenance coefficient Ssc is fitted with the environmental suitability coefficient Cenv through the quantum state preparation optimization model to obtain the phase stability index Pst of the prepared photons;

[0110] The system control module pre-sets a phase stability threshold L, and obtains a phase instability rate Pun by comparing the phase stability index Pst of each photon. The phase instability rate Pun is compared and analyzed with the phase stability threshold L to comprehensively determine whether the environmental noise interference in the current quantum state readout process is within a controllable range. If it is not within the controllable range, a readout adjustment instruction is issued to the outside and corresponding adjustment measures are taken.

[0111] In this embodiment, the data acquisition module extracts the physical parameters related to the phase and frequency of the photons, constructs the initial photon state data set, records the noise level and temperature change of the external environment, and constructs the interference information data set, thereby ensuring the data integrity and comprehensive tracking of external interference during the quantum state readout process; the data preprocessing module eliminates noise interference and unit differences of physical quantities through noise filtering and dimensionless parameter processing, thereby ensuring the consistency and accuracy of the data; the readout analysis module obtains the coherence retention time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph through feature extraction, further calculates the steady-state retention coefficient Ssc and the preparation environment suitability coefficient Cenv, and obtains the phase stability index Pst through the quantum state preparation optimization model, thereby optimizing the quantum state readout and analysis process and improving the stability and reliability of the system; the system control module calculates the phase instability rate Pun by comparing the phase stability index Pst with the phase stability threshold L, and evaluates the environmental noise interference according to the comparison result of the phase instability rate Pun with the phase stability threshold L, and issues an adjustment instruction in time when the noise exceeds the controllable range, thereby ensuring the high precision and phase stability of the system during the readout process.

[0112] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A quantum state preparation method based on a coherent light source, characterized in that: The following steps are involved: S1. Extract the physical parameters related to the phase and frequency of photons from the coherent light source system in advance and construct an initial photon state data set; then track and record the noise level and temperature changes of the external environment, and finally construct an interference information data set; S2, performing data preprocessing on the initial photon state data set and the interference information data set obtained in step S1, including noise filtering and parameter dimensionless processing; then, extracting relevant noise model information prepared by the corresponding quantum state according to the interference information data set; S3, extract the initial photon state data set and the interference information data set after preprocessing for calculation, and obtain the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph respectively; obtain and evaluate the steady-state maintenance coefficient Ssc in the preparation process by associating the coherence maintenance time Tco with the interference noise level Nno; according to the evaluation content of the steady-state maintenance coefficient Ssc, fit the ambient temperature change value Thb and the number of photons Nph to further calculate and evaluate the current preparation environment suitability coefficient Cenv and evaluate it; finally, combine the quantum neural network with the relevant noise model information to construct a quantum state preparation optimization model and after training, fit the steady-state maintenance coefficient Ssc with the preparation environment suitability coefficient Cenv through the quantum state preparation optimization model to obtain the phase stability index Pst of the prepared photons; S4. Compare the preset phase stability threshold L with the phase stability index Pst to obtain the phase instability rate Pun. By comparing and evaluating the phase instability rate Pun with the phase stability threshold L, and comprehensively judging whether the environmental noise interference in the current quantum state preparation process is within the controllable range based on the evaluation content of the phase instability rate Pun, if it is not within the controllable range, issue a preparation adjustment instruction to the outside and take corresponding adjustment measures.

2. The method for preparing a quantum state based on a coherent light source according to claim 1, characterized in that: S11, the physical parameters related to the phase and frequency of photons are respectively obtained by monitoring and recording through the phase detection device, the spectrometer and the photon detector; wherein the initial photon state data set includes the phase jitter amplitude Gxd, the photon frequency deviation Gpc, the phase noise spectral density Gxw, the photon emission rate Gfs, the photon detection efficiency Gjc and the attenuation coefficient Gsj; S12, the noise level and temperature change of the external environment are collected by the environmental noise sensor, spectrum analyzer and temperature sensor respectively; The interference information data set includes the environmental background noise intensity Hbj, the electronic noise intensity Hnb inside the device, the optical noise intensity Hgz, the instantaneous temperature Hsw, the temperature change rate Hwb and the internal temperature of the device Hsb.

3. The method for preparing a quantum state based on a coherent light source according to claim 2, characterized in that: S21, performing noise filtering and outlier processing on the initial photon state data set and the interference information data set, wherein the noise filtering includes removing environmental noise by a low-pass filter or a Kalman filter, and the outlier processing includes correcting sudden abnormal data by an interpolation method or a mean compensation method; S22. Dimensionally transforming the preprocessed data, and extracting data for analyzing the influence of noise interference in the quantum state preparation process based on the dimensionally transformed interference information data set.

4. The method for preparing a quantum state based on a coherent light source according to claim 3, characterized in that: S31, extracting the initial photon state data set and the interference information data set, and calculating the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the photon number Nph by the following formulas respectively: Nno=Hbj+Hnb+Hgz; Nph = Gfs × Gjc × (1-Gsj); Where t represents the time interval.

5. The method for preparing a quantum state based on a coherent light source according to claim 4, characterized in that: S32, the specific calculation and evaluation contents of the steady-state retention coefficient Ssc are as follows: By presetting the steady-state holding threshold Q and comparing it with the steady-state holding coefficient Ssc, the following evaluation content is generated: When the steady-state preservation coefficient Ssc ≥ the steady-state preservation threshold Q, it means that the coherence and steady-state preservation capabilities in the quantum state preparation process are in compliance. At this time, no additional adjustment is required and the current preparation environment continues to be evaluated; When the steady-state maintenance coefficient Ssc is less than the steady-state maintenance threshold Q, it means that the coherence and steady-state maintenance ability in the quantum state preparation process do not meet the tolerable range of the system. At this time, adjustment measures need to be taken, including adding a shielding layer, improving the noise filtering algorithm, and adjusting the environmental control until the steady-state maintenance coefficient Ssc meets the tolerable range of the system.

6. The method for preparing a quantum state based on a coherent light source according to claim 5, characterized in that: S33, extracting the ambient temperature change value Thb and the number of photons Nph and calculating the preparation environment suitability coefficient Cenv using the following formula: The evaluation is performed by presetting the environmental suitability threshold W and the preparation environmental suitability coefficient Cenv. The specific evaluation contents are as follows: When the preparation environment suitability coefficient Cenv ≥ the environmental suitability threshold W, it indicates that the current preparation environment is suitable for quantum state preparation and no additional adjustment is required; When the preparation environment suitability coefficient Cenv is less than the environmental suitability threshold W, it indicates that the current preparation environment is not suitable for quantum state preparation. The specific reasons include excessive temperature changes or insufficient number of photons. At this time, measures should be taken to make adjustments, including adjusting the ambient temperature, reducing interference and increasing the photon emission rate.

7. The method for preparing a quantum state based on a coherent light source according to claim 6, characterized in that: S34. The specific calculation formula for the phase stability index Pst of the prepared photons is: Pst = α·Ssc + β·Cenv; In the formula, α represents the weight value of the steady-state maintenance coefficient Ssc, β represents the weight value of the preparation environment suitability coefficient Cenv; and α+β=1, 0<α≤1, 0<β≤1.

8. The method for preparing a quantum state based on a coherent light source according to claim 7, characterized in that: S41, the specific formula for obtaining the phase instability rate Pun is as follows: L is the phase stability threshold.

9. The method for preparing a quantum state based on a coherent light source according to claim 8, characterized in that: S42. By comparing the phase instability rate Pun with the phase stability threshold L, the environmental noise interference in the current quantum state preparation process is evaluated, and a comprehensive judgment is made as to whether the noise is within a controllable range. The specific evaluation content is: If the phase instability rate Pun ≤ the phase stability threshold L, it means that the system noise interference is within the controllable range, the quantum state preparation process is stable, and no intervention is required; If the phase instability rate Pun is greater than the phase stability threshold L, it means that the system noise interference is not within the controllable range. At this time, a preparation adjustment instruction is issued and corresponding adjustment measures are taken, including adjusting the physical environment of quantum state preparation, adjusting the noise source and system stability.

10. A quantum state readout system based on a coherent light source, according to the quantum state preparation method based on a coherent light source according to any one of claims 1 to 9, characterized in that: It includes data acquisition module, data preprocessing module, readout analysis module and system control module; The data acquisition module extracts physical parameters related to the phase and frequency of photons from the coherent light source system in advance to construct an initial photon state data set, and simultaneously tracks and records the noise level and temperature changes of the external environment to construct an interference information data set; The data preprocessing module performs data preprocessing on the acquired initial photon state data set and interference information data set, including noise filtering and parameter dimensionless processing; The readout analysis module performs feature extraction on the preprocessed initial photon state data set and the interference information data set to respectively obtain the coherence maintenance time Tco, the interference noise level Nno, the ambient temperature change value Thb and the number of photons Nph; obtains and evaluates the steady-state maintenance coefficient Ssc in the preparation process by associating the coherence maintenance time Tco with the interference noise level Nno; according to the evaluation content of the steady-state maintenance coefficient Ssc, fits the ambient temperature change value Thb and the number of photons Nph to further calculate and evaluate the current preparation environment suitability coefficient Cenv and evaluates it; finally, the quantum neural network is combined with the relevant noise model information to construct a quantum state preparation optimization model and after training, the steady-state maintenance coefficient Ssc is fitted with the environmental suitability coefficient Cenv through the quantum state preparation optimization model to obtain the phase stability index Pst of the prepared photons; The system control module pre-sets a phase stability threshold L, and obtains a phase instability rate Pun by comparing the phase stability index Pst of each photon. The phase instability rate Pun is compared and analyzed with the phase stability threshold L to comprehensively determine whether the environmental noise interference in the current quantum state readout process is within a controllable range. If it is not within the controllable range, a readout adjustment instruction is issued to the outside and corresponding adjustment measures are taken.

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