Method and device for testing quantum bit frequency parameters, and quantum computer

Abstract

The application discloses a kind of quantum bit frequency parameter test method and device, quantum computer, the test method first obtains the physical model of the frequency parameter of to-be-measured quantum bit, the physical model is used for the theoretical expected value of the frequency parameter. Then first experiment is carried out to the to-be-measured quantum bit, and the first frequency spectrum of the to-be-measured quantum bit is obtained, wherein the first frequency spectrum is used to obtain the frequency parameter of the to-be-measured quantum bit. Finally, whether the frequency parameter of the to-be-measured quantum bit meets the requirements is judged based on the physical model and the first frequency spectrum. The test method of quantum bit frequency parameter based on the application tests quantum bit parameter, the whole test process does not need manual intervention, can realize quickly judging whether quantum bit parameter meets the requirements, improves the execution efficiency of quantum chip test process to a certain extent.

Description

Technical Field

[0001] This invention relates to the field of quantum computing, and in particular to a method and apparatus for testing the frequency parameters of qubits, and a quantum computer. Background Technology

[0002] Quantum computing and quantum information is an interdisciplinary field that uses the principles of quantum mechanics to perform computational and information processing tasks. It is closely related to quantum physics, computer science, and informatics. It has experienced rapid development in the last two decades. Quantum algorithms based on quantum computers have demonstrated performance far exceeding that of existing classical computer-based algorithms in scenarios such as factorization and unstructured search, leading to expectations that this field will surpass current computing capabilities. Because quantum computing has the potential to far exceed the performance of classical computers in solving specific problems, realizing a quantum computer requires a quantum chip containing a sufficient number and quality of qubits, and the ability to perform extremely high-fidelity quantum logic gate operations and readouts of these qubits.

[0003] A quantum chip is to a quantum computer what a CPU is to a traditional computer; it's the core component of a quantum computer, acting as the processor to perform quantum calculations. A quantum chip integrates multiple qubits and other devices. Before each quantum chip is officially put into use, its various parameters need to be tested and characterized, with frequency parameters being a crucial component. Frequency parameters include, but are not limited to, the transition frequencies of the qubits, which are the frequencies required for a qubit to transition from its ground state to an excited state. During the testing phase, a drive signal is applied to the qubit, and its amplitude is scanned within a set frequency range to obtain its spectrum. The frequency parameters of the qubit can then be derived from the spectrum. Current technologies for testing qubit frequency parameters typically rely on manual judgment by staff based on past experience and test results. This approach is inefficient and significantly impacts the efficiency of the testing process.

[0004] Therefore, proposing a solution to improve the testing efficiency of quantum chips has become an 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 intended only to enhance the understanding of the general background of this application, and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a method and apparatus for testing the frequency parameters of qubits, as well as a quantum computer, to solve the problem of low testing efficiency in existing technologies.

[0007] To address the above technical problems, this invention proposes a method for testing the frequency parameters of quantum bits, comprising:

[0008] A physical model is obtained for the frequency parameters of the sub-bit to be measured, and the physical model is used for the theoretical expected value of the frequency parameters;

[0009] A first experiment is performed on the sub-bit to be measured to obtain a first spectrum of the sub-bit to be measured, wherein the first spectrum is used to obtain the frequency parameters of the sub-bit to be measured;

[0010] Based on the physical model and the first spectrum diagram, it is determined whether the frequency parameters of the sub-bit to be measured meet the requirements.

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

[0012] The spectral curve containing both frequency and amplitude satisfies:

[0013]

[0014] A=κπ(y max -y min )

[0015] Where x is the frequency, y is the amplitude, к is the half-width at half-maximum (WHM) of the spectrum of the theoretically expected value, and y max Let y be the maximum value. min Let C be the minimum value of y, and let C be the average value of y.

[0016] Optionally, the first experiment includes:

[0017] The power of the driving signal applied to the sub-bit to be measured is adjusted so that a resonance peak exists in the second spectrum of the sub-bit to be measured.

[0018] Based on the second spectrum, the frequency range of the drive signal scan is adjusted to obtain the first spectrum.

[0019] Optionally, adjusting the power of the driving signal applied to the sub-bit to be measured so that the second spectrum of the acquired sub-bit to be measured has a resonance peak includes:

[0020] Determine the initial power of the drive signal;

[0021] The driving signal is applied to the sub-bit to be measured, and it is determined whether there is a resonance peak in the second spectrum.

[0022] If so, output the second spectrogram;

[0023] If not, the current power of the driving signal is increased by the set value, and the process returns to applying the driving signal to the sub-bit to be measured, and it is determined whether there is a resonance peak in the second spectrum.

[0024] Optionally, the step of adjusting the frequency range of the driving signal scan based on the second spectrum to obtain the first spectrum includes:

[0025] The frequency range of the driving signal scan is adjusted based on the position of the resonant peak in the second spectrum.

[0026] The first spectrum is obtained based on the adjusted driving signal.

[0027] Optionally, adjusting the frequency range of the driving signal scan based on the position of the resonant peak in the second spectrum includes:

[0028] Based on the frequency corresponding to the resonant peak in the second spectrum, the frequency range of the driving signal scan is narrowed.

[0029] Optionally, determining whether the frequency parameters of the sub-bit to be measured meet the requirements based on the physical model and the first spectrogram includes:

[0030] The theoretical expected value of the frequency parameter is obtained using the physical model.

[0031] Based on the theoretical expected value, the deviation of the frequency parameter of the sub-bit to be measured in the first spectrum is obtained;

[0032] Based on the degree of deviation, it is determined whether the frequency parameters of the sub-bit to be measured meet the requirements.

[0033] Optionally, obtaining the deviation of the frequency parameter of the sub-bit to be measured in the first spectrum based on the theoretical expected value includes:

[0034] The degree of offset is obtained by using the goodness of fit to the theoretical expected value and the frequency parameters of the sub-bit to be measured in the first spectrum.

[0035] Optionally, obtaining the offset degree using goodness of fit on the theoretical expected value and the frequency parameters of the sub-bit to be measured in the first spectrum includes:

[0036] Construct the first formula, which is:

[0037]

[0038] Among them, R 2 For the degree of offset, y fit For the theoretical expected value, yraw The frequency parameter of the sub-bit to be measured in the first spectrum diagram. The average value of the frequency parameters of the sub-bit to be measured in the first spectrum diagram;

[0039] The degree of offset is obtained using the first formula.

[0040] Optionally, determining whether the frequency parameter of the sub-bit to be measured meets the requirements based on the degree of deviation includes:

[0041] Determine the R 2 Is it greater than 0.6?

[0042] If not, then the frequency parameter of the sub-bit to be measured is determined to be non-compliant.

[0043] If so, determine whether the resonance peak in the first spectrum diagram undergoes Rabi oscillation;

[0044] If not, the frequency parameter of the sub-bit to be measured is determined to be non-compliant.

[0045] If so, then determine the number of resonance peaks in the first spectrum.

[0046] If the number of resonance peaks in the first spectrum is one, then the frequency parameters of the sub-bit to be measured are determined to meet the requirements.

[0047] If there are two resonant peaks in the first spectrum, then determine whether the distance between the two resonant peaks is within the set range;

[0048] If so, then the frequency parameters of the sub-bit to be measured are determined to meet the requirements;

[0049] If not, then the frequency parameters of the sub-bit to be measured are determined to be non-compliant.

[0050] Based on the same inventive concept, this invention also proposes a device for testing the frequency parameters of quantum bits, comprising:

[0051] A physical model acquisition module is configured to acquire a physical model of the frequency parameters of the sub-bit to be measured, the physical model being used for the theoretical expected value of the frequency parameters;

[0052] A spectrum acquisition module is configured to perform a first experiment on the sub-bit to be measured and acquire a first spectrum of the sub-bit to be measured, wherein the first spectrum is used to acquire the frequency parameters of the sub-bit to be measured;

[0053] The judgment module is configured to determine whether the frequency parameters of the sub-bit to be measured meet the requirements based on the physical model and the first spectrum diagram.

[0054] Based on the same inventive concept, the present invention also proposes a quantum control system, which uses the test method for the quantum bit frequency parameter described in any one of the above-described features to determine the quantum bit frequency parameter, or includes the test device for the quantum bit frequency parameter described in the above-described features.

[0055] Based on the same inventive concept, the present invention also proposes a quantum computer, including the quantum control system described in the above feature description.

[0056] Based on the same inventive concept, the present invention also proposes a readable storage medium storing a computer program thereon, which, when executed by a processor, can implement the method for testing the frequency parameters of the quantum bits as described in any of the above-described features.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] This invention proposes a method for testing the frequency parameters of a qubit. First, a physical model of the frequency parameters of the qubit to be measured is obtained, whereby the physical model represents the theoretical expected value of the frequency parameters. Next, a first experiment is performed on the qubit to be measured, obtaining a first spectrum of the qubit, whereby the first spectrum is used to determine the frequency parameters of the qubit to be measured. Finally, based on the physical model and the first spectrum, it is determined whether the frequency parameters of the qubit to be measured meet the requirements. This method for testing the frequency parameters of qubits eliminates the need for manual intervention throughout the testing process, enabling rapid determination of whether the qubit parameters meet the requirements and improving the efficiency of quantum chip testing to a certain extent.

[0059] The quantum bit frequency parameter testing device, quantum control system, quantum computer, and readable storage medium proposed in this invention belong to the same inventive concept as the quantum bit frequency parameter testing method, and therefore have the same beneficial effects, which will not be elaborated here. Attached Figure Description

[0060] Figure 1 This is a flowchart illustrating a method for testing the frequency parameters of a quantum bit according to an embodiment of the present invention.

[0061] Figure 2 This is a schematic diagram of the first type of spectrum diagram exemplified in the embodiments of the present invention;

[0062] Figure 3 This is a schematic diagram of the second type of spectrum diagram exemplified in an embodiment of the present invention;

[0063] Figure 4 This is a schematic diagram of the third type of spectrum diagram exemplified in the embodiments of the present invention;

[0064] Figure 5 This is a schematic diagram of the fourth type of spectrum diagram exemplified in the embodiments of the present invention;

[0065] Figure 6 This is a schematic diagram of the fifth type of spectrum diagram exemplified in the embodiments of the present invention;

[0066] Figure 7 This is a schematic diagram of a test device for quantum bit frequency parameters according to another embodiment of the present invention. Detailed Implementation

[0067] The specific embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0068] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0070] Please refer to Figure 1 This invention provides a method for testing the frequency parameters of a quantum bit, comprising:

[0071] S10: Obtain a physical model of the frequency parameters of the sub-bit to be measured, wherein the physical model is used for the theoretical expected value of the frequency parameters;

[0072] S20: Perform a first experiment on the sub-bit to be measured to obtain a first spectrum of the sub-bit to be measured, wherein the first spectrum is used to obtain the frequency parameters of the sub-bit to be measured;

[0073] S30: Based on the physical model and the first spectrum diagram, determine whether the frequency parameters of the sub-bit to be measured meet the requirements.

[0074] Unlike existing technologies, this embodiment proposes a method for testing the frequency parameters of a qubit. First, a physical model of the frequency parameters of the qubit to be measured is obtained, whereby the physical model represents the theoretical expected value of the frequency parameters. Next, a first experiment is performed on the qubit to be measured, obtaining a first spectrum of the qubit. This first spectrum is used to determine the frequency parameters of the qubit. Finally, based on the physical model and the first spectrum, it is determined whether the frequency parameters of the qubit meet the requirements. This method for testing the frequency parameters of qubits eliminates the need for manual intervention throughout the testing process, enabling rapid determination of whether the qubit parameters meet the requirements and improving the efficiency of quantum chip testing to a certain extent.

[0075] Those skilled in the art will understand that the first experiment refers to an energy spectrum experiment, and the driving signal refers to the driving signal applied to the corresponding qubit in the energy spectrum experiment. The energy spectrum experiment of a qubit refers to applying a continuous frequency f to a qubit. d The driving signal causes the qubit to transition from the ground state to the excited state. After the driving signal ends, a readout pulse signal is applied to the qubit to obtain the probability distribution P1(f) of the excited state of the qubit. d With the frequency f of the driving signal d The relationship between the frequency f of the driving signal and the frequency f. d When the frequency f0 of the qubit is very close, the qubit can be effectively excited, resulting in an excited state distribution P1(f0) of the qubit. d The frequency of the driving signal increases. However, when the frequency of the driving signal is far from the true frequency of the quantum bit, P1(f) increases. d () approaches 0.

[0076] Because of the inherent noise in quantum chips, if the initial power setting is not appropriate, the experimental results will be buried in the noise fluctuations, making it impossible to obtain the desired spectral curve. Therefore, when conducting the first energy spectrum experiment on the sub-bit to be measured, a higher power driving signal and a wider frequency scanning range are selected. For example, the frequency scanning range is set to [4000MHz, 6000MHz], the resolution is set to 5MHz, and the power of the driving signal is set to -29dB.

[0077] Specifically, the applicant has established a physical model of the frequency parameters. This physical model primarily reflects the spectral curve of the qubit under theoretical conditions. Those skilled in the art will understand that the frequency parameters of the qubit can be obtained from its spectral curve. In this embodiment, the frequency parameters refer to the frequency of the qubit under test transitioning from the |0> state to the |1> state, i.e., f.01 The physical model for the frequency parameters includes:

[0078] The spectral curve containing both frequency and amplitude satisfies:

[0079]

[0080] A=κπ(y max -y min );

[0081] Where x is the frequency, y is the amplitude, к is the half-width at half-maximum (WHM) of the spectrum of the theoretically expected value, and y max Let y be the maximum value. min Let C be the minimum value of y, and let C be the average value of y.

[0082] Specifically, in this embodiment, the first experiment includes:

[0083] Step 1: Adjust the power of the driving signal applied to the sub-bit to be measured so that the second spectrum of the sub-bit to be measured has a resonance peak;

[0084] Step 2: Adjust the frequency range of the drive signal scan based on the second spectrum diagram to obtain the first spectrum diagram.

[0085] When performing an energy spectrum experiment on the sub-bit to be measured, a relatively wide initial frequency scanning range is used to more easily obtain the resonance peak in the spectrum. However, this results in poor accuracy of the frequency read at the resonance peak. Therefore, after obtaining the spectrum with the resonance peak for the first time, we need to adjust the frequency range of the driving signal scan using the roughly read frequency to obtain a first spectrum with higher frequency accuracy or resolution. Specifically, adjusting the power of the driving signal applied to the sub-bit to be measured so that the second spectrum of the sub-bit to be measured contains a resonance peak includes:

[0086] Determine the initial power of the drive signal;

[0087] The driving signal is applied to the sub-bit to be measured, and it is determined whether there is a resonance peak in the second spectrum.

[0088] If so, output the second spectrogram;

[0089] If not, the current power of the driving signal is increased by the set value, and the process returns to applying the driving signal to the sub-bit to be measured, and it is determined whether there is a resonance peak in the second spectrum.

[0090] In this embodiment, as described above, in order to improve the frequency accuracy or resolution of the spectrum, further, adjusting the frequency range of the driving signal scan based on the second spectrum to obtain the first spectrum includes:

[0091] The frequency range of the driving signal scan is adjusted based on the position of the resonant peak in the second spectrum.

[0092] The first spectrum is obtained based on the adjusted driving signal.

[0093] Specifically, adjusting the frequency range of the driving signal scan based on the position of the resonant peak in the second spectrum includes:

[0094] Based on the frequency corresponding to the resonant peak in the second spectrum, the frequency range of the driving signal scan is narrowed.

[0095] The step of determining whether the frequency parameters of the sub-bit to be measured meet the requirements based on the physical model and the first spectrum includes:

[0096] The theoretical expected value of the frequency parameter is obtained using the physical model.

[0097] Based on the theoretical expected value, the deviation of the frequency parameter of the sub-bit to be measured in the first spectrum is obtained;

[0098] Based on the degree of deviation, it is determined whether the frequency parameters of the sub-bit to be measured meet the requirements.

[0099] It should be noted that, in this embodiment, the degree of offset refers to the degree of deviation between the first spectrogram and the physical model, for example... Figure 2 curves A1 and A2, Figure 3 curves B1 and B2, Figure 4 Curves C1 and C2 in the diagram, Figure 5 D1 and D2 in the middle, and Figure 6 In the equations E1 and E2, A1, B1, C1, D1, and E1 are all results of the physical model of the frequency parameters, and A2, B2, C2, D2, and E2 are the first spectrograms of the frequency parameters. However, it should be noted that in practical applications, to filter out noise in the experimental results, the first spectrogram is smoothed, that is, A2, B2, C2, D2, and E2 are smoothed to obtain A3, B3, C3, D3, and E3 respectively. Therefore, what we ultimately need to compare are A1, B1, C1, D1, E1 and A3, B3, C3, D3, E3.

[0100] Different application scenarios have different requirements for the degree of offset. For some nodes with low accuracy requirements, experimental results that deviate from a certain range may be acceptable. In this case, the threshold for the degree of offset can be set relatively large. However, for some nodes with high accuracy requirements, the results of energy spectrum experiments need to be very close to the physical model. In this case, the threshold for the degree of offset needs to be set relatively small.

[0101] To obtain the degree of deviation of the results of the first experiment, the applicant proposes to use goodness of fit, which refers to how well the regression line fits the observed values. This mainly involves using the coefficient of determination and the regression standard deviation to test the model's fit to the sample observations. When the explanatory variables are multivariate, an adjusted goodness of fit should be used to address the impact of increased variable elements on the goodness of fit. Assuming a population can be divided into r classes, a sample is obtained from this population—this is a batch of categorical data. We need to use this categorical data to determine whether the probability of each class in the population occurs matches the known probability. For example, to test whether a die is fair, the die can be rolled several times, and the number of times each face appears can be recorded. Based on this data, we can test whether the probability of each face appearing is always 1 / 6. The goodness of fit test is used to test whether the distribution of the population from which a batch of categorical data comes is consistent with a certain theoretical distribution. Specifically, based on the theoretical expected value, obtaining the degree of deviation of the frequency parameters of the sub-bit to be measured in the first spectrum includes:

[0102] The degree of offset is obtained by using the goodness of fit to the theoretical expected value and the frequency parameters of the sub-bit to be measured in the first spectrum.

[0103] Specifically, in this embodiment, obtaining the offset degree using goodness of fit for the theoretical expected value and the frequency parameters of the sub-bit to be measured in the first spectrum includes:

[0104] Construct the first formula, which is:

[0105]

[0106] Among them, R 2 For the degree of offset, y fit For the theoretical expected value, y raw The frequency parameter of the sub-bit to be measured in the first spectrum diagram. The average value of the frequency parameters of the sub-bit to be measured in the first spectrum diagram;

[0107] The degree of offset is obtained using the first formula.

[0108] Furthermore, in this embodiment, determining whether the frequency parameter of the sub-bit to be measured meets the requirements based on the degree of deviation includes:

[0109] Determine the R 2 Is it greater than 0.6?

[0110] If not, then the frequency parameter of the sub-bit to be measured is determined to be non-compliant.

[0111] If so, determine whether the resonance peak in the first spectrum diagram undergoes Rabi oscillation;

[0112] If not, the frequency parameter of the sub-bit to be measured is determined to be non-compliant.

[0113] If so, then determine the number of resonance peaks in the first spectrum.

[0114] If the number of resonance peaks in the first spectrum is one, then the frequency parameters of the sub-bit to be measured are determined to meet the requirements.

[0115] If there are two resonant peaks in the first spectrum, then determine whether the distance between the two resonant peaks is within the set range;

[0116] If so, then the frequency parameters of the sub-bit to be measured are determined to meet the requirements;

[0117] If not, then the frequency parameters of the sub-bit to be measured are determined to be non-compliant.

[0118] In this embodiment, the R 2 The closer the result is to 1, the closer the result of the first spectrum is to the physical model of the frequency parameters. In this embodiment... Figures 2 to 6 For example, Figure 2 In the above, compared with A1, A3 has a different R value. 2 It is 0.964; Figure 3 In the middle, compared with B1, B3 has R 2 It is 0.831; Figure 4 In the above, compared with C1, C3 has a higher R value. 2 It is 0.691; Figure 5 In the above, compared with D1, D3 has a higher R value. 2 It is 0.668; Figure 6 In the middle, compared with E1, E3 has R 2 It is 0.146. Therefore, in this embodiment, Figure 2 , Figure 3 , Figure 4 as well as Figure 5 The frequency parameters shown are satisfactory. Figure 6 The frequency parameters in the code do not meet the requirements.

[0119] Please refer to Figure 7 Based on the same inventive concept, embodiments of this application also propose a testing device for quantum bit frequency parameters, comprising:

[0120] A physical model acquisition module is configured to acquire a physical model of the frequency parameters of the sub-bit to be measured, the physical model being used for the theoretical expected value of the frequency parameters;

[0121] A spectrum acquisition module is configured to perform a first experiment on the sub-bit to be measured and acquire a first spectrum of the sub-bit to be measured, wherein the first spectrum is used to acquire the frequency parameters of the sub-bit to be measured;

[0122] The judgment module is configured to determine whether the frequency parameters of the sub-bit to be measured meet the requirements based on the physical model and the first spectrum diagram.

[0123] It is understood that the physical model acquisition module 100, the spectrum acquisition module 200, and the judgment module 300 can be implemented in a single device, or any one of these modules can be split into multiple sub-modules. Alternatively, at least some of the functions of one or more of the physical model acquisition module 100, the spectrum acquisition module 200, and the judgment module 300 can be combined with at least some of the functions of other modules and implemented in a single functional module. According to embodiments of the present invention, at least one of the physical model acquisition module 100, the spectrum acquisition module 200, and the judgment module 300 can be at least partially implemented as hardware circuitry, 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-package, an application-specific integrated circuit (ASIC), or can be implemented in hardware or firmware in any other reasonable manner by integrating or packaging the circuitry, or in a suitable combination of software, hardware, and firmware implementations. Alternatively, at least one of the physical model acquisition module 100, the spectrum acquisition module 200, and the judgment module 300 can be at least partially implemented as a computer program module, which can perform the functions of the corresponding module when the program is run by a computer.

[0124] Based on the same inventive concept, this application also proposes a quantum control system that uses the quantum bit frequency parameter testing method described in any of the above-described features to determine the quantum bit frequency parameter, or includes the quantum bit frequency parameter testing device described in the above-described features.

[0125] Based on the same inventive concept, embodiments of this application also propose a quantum computer, including the quantum control system described in the above feature description.

[0126] Based on the same inventive concept, embodiments of this application also propose a readable storage medium storing a computer program thereon, which, when executed by a processor, can implement the method for testing the frequency parameters of the quantum bits as described in any of the above-described features.

[0127] The readable storage medium can be a tangible device capable of holding and storing instructions for use by an instruction execution device, such as, but not limited to, electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof. The computer programs described herein can be downloaded from the readable storage medium to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network can include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. Each computing / processing device's network adapter card or network interface receives the computer program from the network and forwards it for storage in a readable storage medium within the respective computing / processing device. The computer program used to perform the operations of this invention can be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status 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 languages. The computer program can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuits, such as programmable logic circuits, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), are personalized by utilizing state information from a computer program. These electronic circuits can execute computer-readable program instructions, thereby realizing various aspects of the present invention.

[0128] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, systems, and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by a computer program. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams. These computer programs can also be stored in a readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the readable storage medium storing the computer program comprises an article of manufacture including instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams.

[0129] A computer program may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the computer program executing on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0130] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," or "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions 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. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0131] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. A method for testing the frequency parameters of a quantum bit, characterized in that, include: A physical model is obtained for the frequency parameters of the sub-bit to be measured, and the physical model is used for the theoretical expected value of the frequency parameters; A first experiment is performed on the sub-bit to be measured to obtain a first spectrum of the sub-bit to be measured, wherein the first spectrum is used to obtain the frequency parameters of the sub-bit to be measured; Based on the physical model and the first spectrum diagram, determine whether the frequency parameters of the sub-bit to be measured meet the requirements; The first experiment includes: The power of the driving signal applied to the sub-bit to be measured is adjusted so that the second spectrum of the sub-bit to be measured has a resonance peak. The power of the driving signal and the frequency range of the driving signal are relatively large so that the second spectrum is not buried in the background noise jitter. Based on the frequency corresponding to the resonant peak in the second spectrum, the frequency range of the driving signal scan is narrowed; Based on the adjusted driving signal, the first spectrum is obtained, wherein the frequency accuracy or resolution of the second spectrum is lower than that of the first spectrum.

2. The method for testing the frequency parameters of a quantum bit as described in claim 1, characterized in that, The physical model of the frequency parameters includes: The spectral curve containing both frequency and amplitude satisfies: Where x is the frequency, y is the amplitude, к is the half-width at half-maximum (WHM) of the spectrum of the theoretically expected value, and y max Let y be the maximum value. min Let C be the minimum value of y, and let C be the average value of y.

3. The method for testing the frequency parameters of a quantum bit as described in claim 1, characterized in that, The adjustment of the power of the driving signal applied to the sub-bit to be measured, so that the second spectrum of the acquired sub-bit to be measured has a resonance peak, includes: Determine the initial power of the drive signal; The driving signal is applied to the sub-bit to be measured, and it is determined whether there is a resonance peak in the second spectrum. If so, output the second spectrogram; If not, the current power of the driving signal is increased by the set value, and the process returns to applying the driving signal to the sub-bit to be measured, and it is determined whether there is a resonance peak in the second spectrum.

4. The method for testing the frequency parameters of a quantum bit as described in claim 1, characterized in that, The step of determining whether the frequency parameters of the sub-bit to be measured meet the requirements based on the physical model and the first spectrum includes: The theoretical expected value of the frequency parameter is obtained using the physical model. Based on the theoretical expected value, the deviation of the frequency parameter of the sub-bit to be measured in the first spectrum is obtained; Based on the degree of deviation, it is determined whether the frequency parameters of the sub-bit to be measured meet the requirements.

5. The method for testing the frequency parameters of a quantum bit as described in claim 4, characterized in that, The step of obtaining the deviation of the frequency parameter of the sub-bit to be measured in the first spectrum based on the theoretical expected value includes: The degree of deviation is obtained by using goodness of fit to the theoretical expected value and the frequency parameters of the sub-bit to be measured in the first spectrum.

6. The method for testing the frequency parameters of a quantum bit as described in claim 5, characterized in that, The step of obtaining the degree of deviation from the theoretical expected value and the frequency parameters of the sub-bit to be measured in the first spectrum using goodness of fit includes: Construct the first formula, which is: Among them, R 2 y represents the degree of deviation. fit For the theoretical expected value, y raw The frequency parameter of the sub-bit to be measured in the first spectrum diagram. The average value of the frequency parameters of the sub-bit to be measured in the first spectrum diagram; The degree of deviation is obtained using the first formula.

7. The method for testing the frequency parameters of a quantum bit as described in claim 6, characterized in that, The step of determining whether the frequency parameters of the sub-bit to be measured meet the requirements based on the degree of deviation includes: Determine the R 2 Is it greater than 0.6? If not, then the frequency parameter of the sub-bit to be measured is determined to be non-compliant. If so, determine whether the resonance peak in the first spectrum diagram undergoes Rabi oscillation; If not, the frequency parameter of the sub-bit to be measured is determined to be non-compliant. If so, then determine the number of resonance peaks in the first spectrum. If the number of resonance peaks in the first spectrum is one, then the frequency parameters of the sub-bit to be measured are determined to meet the requirements. If there are two resonant peaks in the first spectrum, then determine whether the distance between the two resonant peaks is within the set range; If so, then the frequency parameters of the sub-bit to be measured are determined to meet the requirements; If not, then the frequency parameters of the sub-bit to be measured are determined to be non-compliant.

8. A device for testing the frequency parameters of a quantum bit, characterized in that, include: A physical model acquisition module is configured to acquire a physical model of the frequency parameters of the sub-bit to be measured, the physical model being used for the theoretical expected value of the frequency parameters; A spectrum acquisition module is configured to perform a first experiment on the sub-bit to be measured and acquire a first spectrum of the sub-bit to be measured, wherein the first spectrum is used to acquire the frequency parameters of the sub-bit to be measured; The judgment module is configured to determine whether the frequency parameters of the sub-bit to be measured meet the requirements based on the physical model and the first spectrum diagram. The first experiment includes: The power of the driving signal applied to the sub-bit to be measured is adjusted so that the second spectrum of the sub-bit to be measured has a resonance peak. The power of the driving signal and the frequency range of the driving signal are relatively large so that the second spectrum is not buried in the background noise jitter. Based on the frequency corresponding to the resonant peak in the second spectrum, the frequency range of the driving signal scan is narrowed; Based on the adjusted driving signal, the first spectrum is obtained, wherein the frequency accuracy or resolution of the second spectrum is lower than that of the first spectrum.

9. A quantum control system, characterized in that, The frequency parameters of a quantum bit are determined using the testing method for quantum bit frequency parameters as described in any one of claims 1-7, or the testing device for quantum bit frequency parameters as described in claim 8.

10. A quantum computer, characterized in that, Including the quantum control system as described in claim 9.

11. 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 method for testing the frequency parameters of the qubits as described in any one of claims 1 to 7.

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