Test method and device for reading cavity parameters and quantum computer

Abstract

The application discloses a test method and device for reading cavity parameters and a quantum computer. A physical model for reading cavity parameters is acquired, wherein the physical model is used to acquire a theoretical expected value of the reading cavity parameters, then a modulation condition of a bias voltage signal of a to-be-tested quantum bit on a frequency of the reading cavity is acquired, and finally it is determined whether the reading cavity parameters meet the requirements based on the theoretical expected value and the modulation condition. The test method for reading cavity parameters provided in the application tests the reading cavity parameters, and the whole test does not need manual intervention, can quickly determine whether the reading cavity parameters meet the requirements, and improves the execution efficiency of a quantum chip test process to a certain extent.

Description

Technical Field

[0001] The present invention relates to the field of quantum computing, and in particular to a test method and device for reading cavity parameters, and a quantum computer. Background Art

[0002] Quantum computing and quantum information are interdisciplinary fields that use the principles of quantum mechanics to achieve computational and information processing tasks. They are closely connected to disciplines such as quantum physics, computer science, and informatics. They have experienced rapid development over the past two decades. Quantum algorithms based on quantum computers, for tasks such as factorization and unstructured search, have demonstrated performance far exceeding that of existing algorithms based on classical computers, leading to expectations that this field will surpass current computing capabilities. Quantum computing has the potential to significantly surpass the performance of classical computers in solving specific problems. To realize a quantum computer, it is necessary to obtain a quantum chip containing a sufficient number and quality of quantum bits (qubits), capable of performing and reading quantum logic gates with extremely high fidelity.

[0003] A quantum chip is to a quantum computer what a CPU is to a traditional computer. The quantum chip is the core component of a quantum computer and the processor that performs quantum computations. It integrates multiple, one-to-one, coupled quantum bits and readout cavities. The section of each readout cavity away from the corresponding quantum bit is connected to a readout signal transmission line integrated on the quantum chip. Each quantum bit is coupled to an XY signal transmission line and a Z signal transmission line. The XY signal transmission line is used to receive quantum state control signals, while the Z signal transmission line is used to receive magnetic flux control signals. The magnetic flux control signals include bias voltage signals and / or pulse bias control signals, both of which can control the frequency of the quantum bit. The readout signal transmission line is used to receive readout detection signals and transmit readout feedback signals. Before each quantum chip is officially put into operation, various parameters of the quantum chip must be tested and characterized. The read cavity parameters are a key component. The read cavity parameters include the modulation of the read cavity by the bias voltage signal. During the testing phase, the modulation of the read cavity by the bias voltage signal can be tested to determine the coupling state between the quantum bit and the read cavity. The test results need to be used to determine whether the read cavity parameters meet the requirements. The existing technology to address this problem usually relies on manual judgment based on past experience and test results. This solution is inefficient and greatly affects the execution efficiency of the testing process.

[0004] Therefore, proposing a solution that can improve the efficiency of quantum chip testing is becoming an increasingly urgent problem to be solved in this field.

[0005] It should be noted that the information disclosed in the background section of this application is only intended to deepen the understanding of the general background of the application and should not be regarded as acknowledging or implying in any form that the information constitutes prior art known to those skilled in the art. SUMMARY

[0006] The purpose of the present application is to provide a test method, device and quantum computer for reading cavity parameters, which can solve the problem of low efficiency in the test process of quantum chips in the prior art.

[0007] In order to solve the above technical problems, the present application provides a test method for reading cavity parameters, which is used in a quantum bit system including a reading cavity and a quantum bit to be tested coupled with the reading cavity, and the test method includes:

[0008] Obtaining a physical model of the reading cavity parameters, wherein the physical model is used to obtain a theoretically expected value of the reading cavity parameters;

[0009] Obtaining a modulation condition of a bias voltage signal of the quantum bit to be tested on the frequency of the reading cavity;

[0010] Judging whether the reading cavity parameters meet the requirements based on the theoretically expected value and the modulation condition.

[0011] Optionally, the physical model of the reading cavity parameters includes:

[0012] The modulation of the bias voltage signal on the reading cavity f r (v) satisfies:

[0013]

[0014] Wherein, f q (v) represents the modulation of the bias voltage signal on the quantum bit frequency, g represents the coupling strength of the reading cavity and the quantum bit, δ represents the difference of the detuning amount of the quantum bit and the reading cavity, f c represents the anharmonicity of the quantum bit.

[0015] Optionally, the obtaining of the modulation condition of the bias voltage signal of the quantum bit to be tested on the frequency of the reading cavity includes:

[0016] Scanning the bias voltage signal within a pre-configured first range;

[0017] Obtaining the frequency variation condition of the reading cavity within the first range;

[0018] Obtaining the modulation condition based on the frequency variation condition of the reading cavity within the first range.

[0019] Optionally, acquiring the modulation condition based on the frequency change of the reading cavity within the first range includes:

[0020] Fitting processing is performed on the frequency change of the reading cavity within the first range to obtain the modulation condition.

[0021] Optionally, judging whether the reading cavity parameters meet requirements based on the theoretical expected value and the modulation condition includes:

[0022] Obtaining theoretical expected values ​​of the reading cavity parameters using the physical model;

[0023] Based on the theoretical expected value, obtaining a deviation degree of the modulation condition;

[0024] It is determined whether the reading cavity parameters meet the requirements based on the degree of deviation.

[0025] Optionally, obtaining the degree of deviation of the modulation condition based on the theoretical expected value includes:

[0026] The degree of deviation is obtained by using goodness of fit for the theoretical expected value and the modulation condition.

[0027] Optionally, obtaining the degree of deviation by using goodness of fit for the theoretical expected value and the modulation condition includes:

[0028] Construct a first formula, which is:

[0029]

[0030] Among them, R 2 is the degree of deviation, y fit is the theoretical expected value, y raw For the modulation situation, is the average value of the modulation condition;

[0031] The deviation degree is obtained using the first formula.

[0032] Optionally, judging whether the reading chamber parameters meet the requirements based on the deviation degree includes:

[0033] In the R 2 When it is greater than 0.95, it is determined that the reading cavity parameters meet the requirements.

[0034] Optionally, judging whether the reading chamber parameters meet the requirements based on the deviation degree further includes:

[0035] In the R 2 When it is less than or equal to 0.95, the R 2Is it greater than 0.9?

[0036] If not, it is determined that the reading cavity parameters do not meet the requirements;

[0037] If so, determining whether there is an extreme point in the modulation condition;

[0038] If so, it is determined that the reading cavity parameters do not meet the requirements;

[0039] If not, the scanning range of the bias voltage signal is adjusted, and the process returns to executing the modulation condition of the frequency of the reading cavity by the bias voltage signal of the sub-bit to be measured.

[0040] Optionally, adjusting the scanning range of the bias voltage signal includes:

[0041] Increase the scanning range of the bias voltage signal.

[0042] Based on the same inventive concept, the present application also proposes a test device for reading cavity parameters, which is used in a quantum bit system. The quantum bit system includes a reading cavity and a quantum bit to be measured coupled to the reading cavity. The test device includes:

[0043] a physical model acquisition module, configured to acquire a physical model of a reading cavity parameter, wherein the physical model is used to acquire a theoretical expected value of the reading cavity parameter;

[0044] a modulation condition acquisition module, configured to acquire a modulation condition of the frequency of the reading cavity caused by the bias voltage signal of the sub-bit to be measured;

[0045] A judgment module is configured to judge whether the reading cavity parameters meet the requirements based on the theoretical expected value and the modulation condition.

[0046] Based on the same inventive concept, the present application also proposes a quantum control system, which uses the test method for reading cavity parameters described in any one of the above characteristic descriptions to judge the reading cavity parameters, or includes a test device for reading cavity parameters described in the above characteristic descriptions.

[0047] Based on the same inventive concept, the present application also proposes a quantum computer, including the quantum control system described in the above feature description.

[0048] Based on the same inventive concept, the present application further proposes a readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for testing the reading cavity parameters described in any one of the above-mentioned feature descriptions can be implemented.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The present invention proposes a method for testing reading cavity parameters. This method obtains a physical model of the reading cavity parameters, wherein the physical model is used to obtain theoretical expected values ​​of the reading cavity parameters. The modulation of the reading cavity frequency by the bias voltage signal of the quantum bit to be measured is then determined. Ultimately, based on the theoretical expected values ​​and the modulation, the reading cavity parameters are determined to be qualified. This method, based on the reading cavity parameter testing method proposed in this application, tests the reading cavity parameters without requiring human intervention, enabling rapid determination of qualified reading cavity parameters, thereby improving the efficiency of quantum chip testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic flow chart of a test method for reading cavity parameters proposed in an embodiment of the present invention;

[0052] Figure 2 1 is a modulation curve of the frequency of the reading cavity by the first bias voltage signal exemplified in an embodiment of the present invention;

[0053] Figure 3 1 is a modulation curve of the frequency of the reading cavity by the second bias voltage signal exemplified in an embodiment of the present invention;

[0054] Figure 4 1 is a modulation curve of the frequency of the reading cavity by the third bias voltage signal exemplified in an embodiment of the present invention;

[0055] Figure 5 This is a schematic structural diagram of a testing device for reading cavity parameters according to another embodiment of the present invention. DETAILED DESCRIPTION

[0056] The following describes a specific embodiment of the present invention in more detail with reference to schematic diagrams. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the drawings are greatly simplified and not to exact scale, and are intended solely to facilitate and clearly illustrate the embodiments of the present invention.

[0057] In the description of the present invention, it should be understood that the terms "center", "up", "down", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0058] In addition, the terms "first", "second", etc. are used only for descriptive purposes and should not be construed as implying or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality" is at least two, for example, two, three, etc., unless otherwise explicitly specified.

[0059] Those skilled in the art should understand that in a quantum computer, the quantum chip is a processor for performing quantum computation, a plurality of one-to-one corresponding and mutually coupled quantum bits and read cavities are integrated on the quantum chip, each read cavity is connected to a read signal transmission line integrated on the quantum chip away from a corresponding quantum bit, and each quantum bit is coupled and connected with an XY signal transmission line and a Z signal transmission line. The XY signal transmission line is used to receive a quantum state control signal, the Z signal transmission line is used to receive a magnetic flux control signal, the magnetic flux control signal includes a bias voltage signal (DC voltage) and / or a pulse bias control signal, and the bias voltage signal and the pulse bias control signal can control the frequency of the quantum bit, and the read signal transmission line is used to receive a read detection signal and emit a read feedback signal.

[0060] In addition, it should be noted that the execution process of quantum computation can be briefly described as follows: the frequency of the quantum bit is adjusted to the working frequency by the magnetic flux control signal on the Z signal transmission line, at this time the quantum state control signal is applied to the quantum bit in the initial state through the XY signal transmission line, and the quantum state of the quantum bit after control is read by the read cavity. Specifically, a read detection signal, usually referred to as a read detection signal, is applied through the read signal transmission line, which is usually a microwave signal with a frequency of 4-8GHz, and the quantum state of the quantum bit is determined by analyzing the read feedback signal output by the read signal transmission line. The fundamental reason why the read cavity can read the quantum state of the quantum bit is that different quantum states of the quantum bit produce different dispersion shifts on the read cavity, so that different quantum states of the quantum bit have different responses to the read detection signal applied to the read cavity, and the response signal is called the read feedback signal. Only when the carrier frequency of the read detection signal of the quantum bit is very close to the inherent frequency (also called the resonance frequency) of the read cavity, the read cavity will have a significant difference in response to the read detection signal due to the different quantum states of the quantum bit, that is, the read feedback signal has the maximum distinguishability.

[0061] Please refer to Figure 1 The embodiment of the present application proposes a read cavity parameter test method, which is used for a quantum bit system including a read cavity and a quantum bit to be measured coupled and connected with the read cavity, and the test method includes:

[0062] S10: Acquire a physical model of the reading cavity parameters, wherein the physical model is used to obtain theoretical expected values ​​of the reading cavity parameters;

[0063] S20: Acquire a modulation condition of the frequency of the reading cavity by the bias voltage signal of the sub-bit to be measured;

[0064] S30: judging whether the reading cavity parameters meet the requirements based on the theoretical expected values ​​and the modulation conditions.

[0065] This embodiment differs from the prior art in that it proposes a method for testing reading cavity parameters, which obtains a physical model of the reading cavity parameters. This physical model is used to obtain theoretical expected values ​​of the reading cavity parameters. The modulation of the reading cavity frequency by the bias voltage signal of the quantum bit to be measured is then determined, ultimately determining whether the reading cavity parameters meet requirements based on the theoretical expected values ​​and the modulation. This method, based on the reading cavity parameter testing method proposed in this embodiment, tests the reading cavity parameters without manual intervention, allowing for rapid determination of whether the reading cavity parameters meet requirements, significantly improving the efficiency of the quantum chip testing process.

[0066] Specifically, the applicant established a physical model of the reading cavity parameters. The physical model of the reading cavity parameters mainly reflects the modulation of the reading cavity by the bias voltage signal under theoretical conditions. The physical model of the reading cavity parameters includes:

[0067] The bias voltage signal modulates the reading cavity f r (v) Satisfy:

[0068]

[0069] Among them, f q (v) represents the modulation of the qubit frequency by the bias voltage signal, g represents the coupling strength between the reading cavity and the qubit, δ represents the difference in detuning between the qubit and the reading cavity, and f c represents the anharmonicity of the quantum bit.

[0070] It should be noted that in the embodiment of the present invention, the physical model of the reading cavity refers to the modulation of the reading cavity by the bias voltage signal under theoretical conditions. In fact, there is not only this one type of reading cavity parameters for the quantum chip. For example, there are also intrinsic frequency, internal quality factor, external quality factor, etc. These parameters need to be tested and characterized during the testing process of the quantum chip, but these parameters are not the focus of the protection requested in this application, so they will not be described here one by one.

[0071] In the embodiment of the present application, obtaining the modulation condition of the frequency of the reading cavity by the bias voltage signal of the sub-bit to be measured includes:

[0072] Sweeping the bias voltage signal within a preconfigured first range;

[0073] Acquire frequency variation of the reading cavity within the first range;

[0074] The modulation condition is obtained based on a frequency change condition of the reading cavity within the first range.

[0075] The first range is a pre-configured parameter used to set the scanning range of the bias voltage signal. For example, the bias voltage signal can be set to [-1v, 1v] or [-1.5v, 1.5v]. After setting the scanning range of the bias voltage signal, the frequency variation of the reading cavity within the first range is obtained, and the fitting result is used to draw a modulation curve of the bias voltage signal on the frequency of the reading cavity. Figure 2 Curve A in Figure 3 Curve C in , and Figure 4 Curve E in FIG. 1 is a modulation curve of the bias voltage signal on the frequency of the reading cavity after fitting processing.

[0076] Specifically, in this embodiment, obtaining the modulation condition based on the frequency change of the reading cavity within the first range includes:

[0077] Fitting processing is performed on the frequency change of the reading cavity within the first range to obtain the modulation condition.

[0078] In the embodiment of the present application, judging whether the reading cavity parameters meet the requirements based on the theoretical expected value and the modulation condition includes:

[0079] Obtaining theoretical expected values ​​of the reading cavity parameters using the physical model;

[0080] Based on the theoretical expected value, obtaining a deviation degree of the modulation condition;

[0081] It is determined whether the reading cavity parameters meet the requirements based on the degree of deviation.

[0082] It should be noted that, in this embodiment, the deviation degree refers to the deviation degree between the experimental results and the physical model, for example Figure 2 In the middle curve A and curve B, Figure 3 Curves C and D, and Figure 4 Curve E and curve F in.

[0083] Different application scenarios have different requirements for the degree of deviation. Some nodes with low precision requirements may be able to accept experimental results that deviate within a certain range. In this case, the threshold of the degree of deviation can be set larger. However, for some nodes with higher precision requirements, the experimental results need to be very close to the physical model. In this case, the threshold of the degree of deviation needs to be set smaller.

[0084] In order to obtain the degree of deviation of the experimental results, the applicant proposed to use the goodness of fit to achieve it. The goodness of fit refers to the degree of fit of the regression line to the observed values. It is mainly to use the coefficient of determination and the regression standard deviation to test the degree of fit of the model to the sample observations. When the explanatory variable is multivariate, the adjusted goodness of fit should be used to solve the impact of the increase in variable elements on the goodness of fit. Assume that a population can be divided into r categories, and now a sample is obtained from the population - this is a batch of classified data. We need to start from these classified data to judge whether the probability of each category of the population appearing is consistent with the known probability. For example, if you want to test whether a dice is uniform, you can throw the dice several times and record the number of times each side appears. Starting from these data, you can test whether the probability of each side appearing is 1 / 6. The goodness of fit test is used to test whether the distribution of the population from which a batch of classified data comes is consistent with a certain theoretical distribution. Specifically, the degree of deviation of the modulation situation obtained based on the theoretical expected value includes:

[0085] The degree of deviation is obtained by using goodness of fit for the theoretical expected value and the modulation condition.

[0086] Specifically, in the embodiment of the present application, obtaining the degree of deviation by using goodness of fit for the theoretical expected value and the modulation condition includes:

[0087] Construct a first formula, which is:

[0088]

[0089] Among them, R 2 is the degree of deviation, y fit is the theoretical expected value, y raw For the modulation situation, is the average value of the modulation condition;

[0090] The deviation degree is obtained using the first formula.

[0091] Specifically, in the embodiment of the present application, judging whether the reading cavity parameters meet the requirements based on the deviation degree includes:

[0092] In the R 2When it is greater than 0.95, it is determined that the reading cavity parameters meet the requirements.

[0093] Furthermore, judging whether the reading chamber parameters meet the requirements based on the deviation degree further includes:

[0094] In the R 2 When it is less than or equal to 0.95, the R 2 Is it greater than 0.9?

[0095] If not, it is determined that the reading cavity parameters do not meet the requirements;

[0096] If so, determining whether there is an extreme point in the modulation condition;

[0097] If so, it is determined that the reading cavity parameters do not meet the requirements;

[0098] If not, the scanning range of the bias voltage signal is adjusted, and the process returns to executing the modulation condition of the frequency of the reading cavity by the bias voltage signal of the sub-bit to be measured.

[0099] Specifically, in the embodiment of the present application, adjusting the scanning range of the bias voltage signal includes:

[0100] Increase the scanning range of the bias voltage signal.

[0101] In this embodiment, the R 2 The closer it is to 1, the smaller the degree to which the modulation situation deviates from the theoretical expected value of the physical model, such as Figure 2 Compared with curve A and curve B, its R 2 The value is 0.9993, which perfectly matches the expected physical model. Figure 3 Compared with curve C and curve D, its R 2 The value is 0.9551. This set of data is consistent with the expected physical model, but there may still be jitter in the data. In some situations where the precision requirements are not high, this set of data can be considered to meet the requirements. However, in some situations where the precision requirements are very high, it may not meet the requirements. Figure 4 Compared with curve E and curve F, its R 2 The value is 0.936. This group of data obviously deviates too much from the physical model. Therefore, it can be determined that the reading cavity parameters do not meet the requirements.

[0102] Based on the same invention concept, please refer to Figure 5 The present application also provides a test device for reading cavity parameters, which is used in a quantum bit system. The quantum bit system includes a reading cavity and a quantum bit to be measured coupled to the reading cavity. The test device includes:

[0103] a physical model acquisition module, configured to acquire a physical model of a reading cavity parameter, wherein the physical model is used to acquire a theoretical expected value of the reading cavity parameter;

[0104] a modulation condition acquisition module, configured to acquire a modulation condition of the frequency of the reading cavity caused by the bias voltage signal of the sub-bit to be measured;

[0105] A judgment module is configured to judge whether the reading cavity parameters meet the requirements based on the theoretical expected value and the modulation condition.

[0106] It is understood that the physical model acquisition module 100, the modulation condition acquisition module 200, and the judgment module 300 can be implemented in a single device, or any one of the modules can be split into multiple sub-modules, or at least part of the functionality of one or more of the physical model acquisition module 100, the modulation condition acquisition module 200, and the judgment module 300 can be combined with at least part of the functionality of other modules and implemented in a single functional module. According to an embodiment of the present invention, at least one of the physical model acquisition module 100, the modulation condition acquisition module 200, and the judgment module 300 can be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), a system on a chip, a system on a substrate, a system on a package, an application-specific integrated circuit (ASIC), or can be implemented in hardware or firmware in any other reasonable manner for integrating or packaging circuits, or in an appropriate combination of software, hardware, and firmware. Alternatively, at least one of the physical model acquisition module 100, the modulation condition acquisition module 200 and the judgment module 300 may be at least partially implemented as a computer program module, and when the program is run by a computer, the function of the corresponding module may be executed.

[0107] Based on the same inventive concept, an embodiment of the present application further proposes a quantum control system, which uses the test method for reading cavity parameters described in any one of the above characteristic descriptions to judge the reading cavity parameters, or includes a test device for reading cavity parameters described in the above characteristic descriptions.

[0108] Based on the same inventive concept, an embodiment of the present application also proposes a quantum computer, including the quantum control system described in the above feature description.

[0109] Based on the same inventive concept, an embodiment of the present application further provides a readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it can implement the method for testing the reading cavity parameters described in any one of the above-mentioned feature descriptions.

[0110] The readable storage medium can be a tangible device that can keep and store the instruction used by the instruction execution device, such as, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device or any suitable combination thereof. The more specific example (non-exhaustive list) of readable storage medium includes: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a convex structure in a groove having instructions stored thereon, and any suitable combination thereof. The computer program described herein can be downloaded to each computing / processing device from the readable storage medium, or downloaded to an external computer or external storage device by a network, such as the Internet, a local area network, a wide area network and / or a wireless network. The network can include copper transmission cables, optical fiber transmission, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer program from the network and forwards the computer program for storage in a readable storage medium in each computing / processing device. The computer program for performing the operations of the present invention can be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The computer program can be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (for example, through the Internet using an Internet service provider). In some embodiments, various aspects of the present invention are implemented by utilizing state information of a computer program to personalize an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), which can execute computer-readable program instructions.

[0111] Various aspects of the present invention are described herein with reference to the flowcharts and / or block diagrams of the methods, systems, and computer program products according to embodiments of the present invention. It should be understood that each block of the flowcharts and / or block diagrams, as well as the combination of blocks in the flowcharts and / or block diagrams, can be implemented by computer programs. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine such that when these programs are executed by the processor of the computer or other programmable data processing device, a device is generated that implements the functions / actions specified in one or more blocks in the flowcharts and / or block diagrams. These computer programs can also be stored in a readable storage medium, which causes the computer, programmable data processing device, and / or other device to operate in a specific manner, so that the readable storage medium storing the computer program comprises an article of manufacture comprising instructions for implementing various aspects of the functions / actions specified in one or more blocks in the flowcharts and / or block diagrams.

[0112] The computer program may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operational steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the computer program executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more blocks in the flowchart and / or block diagram.

[0113] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "example," or "specific example" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments. Furthermore, those skilled in the art may combine and reconcile different embodiments or examples described in this specification.

[0114] The above description is merely a preferred embodiment of the present invention and does not limit the present invention in any way. Any person skilled in the art who, without departing from the scope of the present invention, makes any equivalent substitution, modification, or other changes to the technical solution and technical content disclosed in the present invention shall be deemed to be within the scope of the present invention and still fall within the scope of protection of the present invention.

Claims

1. A test method for reading cavity parameters, characterized in that: For a quantum bit system, the quantum bit system includes a reading cavity and a quantum bit to be measured coupled to the reading cavity, the testing method including: Obtaining a physical model of a reading cavity parameter, wherein the physical model is used to obtain a theoretical expected value of the reading cavity parameter; Acquiring a modulation condition of the frequency of the reading cavity by the bias voltage signal of the sub-bit to be measured; It is determined whether the reading cavity parameters meet the requirements based on the theoretical expected values ​​and the modulation condition.

2. The method for reading cavity parameters according to claim 1, wherein: The physical model for reading cavity parameters includes: The bias voltage signal modulates the reading cavity f r (v) Satisfy: Among them, f q (v) represents the modulation of the qubit frequency by the bias voltage signal, g represents the coupling strength between the reading cavity and the qubit, δ represents the difference in detuning between the qubit and the reading cavity, and f c represents the anharmonicity of the quantum bit.

3. The method for testing cavity parameters according to claim 1, wherein: The obtaining of a modulation condition of the frequency of the reading cavity by the bias voltage signal of the sub-bit to be measured includes: Sweeping the bias voltage signal within a preconfigured first range; Acquire frequency variation of the reading cavity within the first range; The modulation condition is obtained based on a frequency change condition of the reading cavity within the first range.

4. The method for testing cavity parameters according to claim 3, wherein: The acquiring the modulation condition based on the frequency change of the reading cavity within the first range includes: A fitting process is performed on the frequency variation of the reading cavity within the first range to obtain the modulation condition.

5. The method for testing cavity parameters according to claim 1, wherein: The determining whether the reading cavity parameters meet the requirements based on the theoretical expected value and the modulation condition includes: Obtaining theoretical expected values ​​of the reading cavity parameters using the physical model; Based on the theoretical expected value, obtaining a deviation degree of the modulation condition; It is determined whether the reading cavity parameters meet the requirements based on the degree of deviation.

6. The method for testing cavity parameters according to claim 5, wherein: The obtaining, based on the theoretical expected value, a degree of deviation of the modulation condition, includes: The degree of deviation is obtained by using goodness of fit for the theoretical expected value and the modulation condition.

7. The method for testing cavity parameters according to claim 6, wherein: The obtaining the degree of deviation by using goodness of fit for the theoretical expected value and the modulation condition includes: Construct a first formula, which is: Among them, R 2 is the degree of deviation, y fit is the theoretical expected value, y raw For the modulation situation, is the average value of the modulation condition; The deviation degree is obtained using the first formula.

8. The method for testing cavity parameters according to claim 7, wherein: The determining whether the reading cavity parameters meet the requirements based on the deviation degree includes: In the R 2 When it is greater than 0.95, it is determined that the reading cavity parameters meet the requirements.

9. The method for testing cavity parameters according to claim 8, wherein: The determining whether the reading chamber parameters meet the requirements based on the deviation degree further includes: In the R 2 When it is less than or equal to 0.95, the R 2 Is it greater than 0.9? If not, it is determined that the reading cavity parameters do not meet the requirements; If so, determining whether there is an extreme value point in the modulation condition; If so, it is determined that the reading cavity parameters do not meet the requirements; If not, the scanning range of the bias voltage signal is adjusted, and the process returns to executing the modulation condition of the frequency of the reading cavity by the bias voltage signal of the sub-bit to be measured.

10. The method for testing cavity parameters according to claim 9, wherein: The adjusting the scanning range of the bias voltage signal includes: Increase the scanning range of the bias voltage signal.

11. A test device for reading cavity parameters, characterized in that: For a quantum bit system, the quantum bit system includes a reading cavity and a quantum bit to be measured coupled to the reading cavity, and the testing device includes: a physical model acquisition module, configured to acquire a physical model of a reading cavity parameter, wherein the physical model is used to acquire a theoretical expected value of the reading cavity parameter; a modulation condition acquisition module, configured to acquire a modulation condition of the frequency of the reading cavity caused by the bias voltage signal of the sub-bit to be measured; A judgment module is configured to judge whether the reading cavity parameters meet the requirements based on the theoretical expected value and the modulation condition.

12. A quantum control system, characterized in that: The reading cavity parameters are judged by using the test method for reading cavity parameters according to any one of claims 1 to 10, or the test device for reading cavity parameters according to claim 11.

13. A quantum computer, characterized in that: Comprising the quantum control system as claimed in claim 12.

14. A readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, it can implement the test method for reading cavity parameters according to any one of claims 1 to 10.

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