A method, device and equipment for calibrating quantum bit operating frequency

Abstract

The present invention proposes a method, device and equipment for calibrating the working frequency of a quantum bit. The method includes the following steps: setting the offset of the current applied signal strength of the quantum bit and the termination condition of the working frequency calibration; in response to reaching the condition for calibrating the working frequency of the quantum bit, calculating the offset working frequency of the quantum bit under the offset, and obtaining the rate of change of the working frequency based on the offset working frequency and the offset; iteratively updating the rate of change of the working frequency and the current applied signal strength by the gradient ascent method until the rate of change of the working frequency is less than the termination condition, and completing the adjustment of the working frequency of the quantum bit to the maximum value of the working frequency under the new applied signal strength. The scheme disclosed in the present invention does not need to test the working frequency of the quantum bit under a large number of flux-controlled DC intensities, saving time and resources.

Description

Technical Field

[0001] The present invention relates to the field of computer technology, and in particular to a method, device and equipment for calibrating the operating frequency of a quantum bit. Background Art

[0002] The frequency-adjustable quantum bit based on the superconducting quantum interference structure (SQUID) is a common superconducting quantum bit design scheme at present. The quantum bit with this structure has the characteristic of adjustable frequency. By changing the DC signal strength added to the flux control line in the quantum bit chip, the size of the magnetic flux passing through the SQUID loop can be changed. By adjusting the size of the magnetic flux, the characteristic operating frequency of the quantum bit can be adjusted within a certain range. This quantum bit design scheme brings more flexibility to the control method of the quantum bit. In the prior art, this method of flux control introduces additional control freedom, making the quantum bit more susceptible to the influence of external electromagnetic noise, thereby resulting in a reduction in the coherence time of the quantum bit decoherence. In order to reduce this interference factor and take into account that the curve of the quantum bit adjusted by the flux signal presents a trigonometric function shape in a single cycle, the DC signal strength added to the flux control line is often adjusted to the maximum point of the quantum bit operating frequency (also known as the "sweet spot", Sweet point, i.e. SP point) in the prior art.

[0003] Due to changes in the external electromagnetic environment, the working frequency of the qubit often deviates from the SP point after working for a period of time. The common way to solve this problem in the prior art is to recalibrate the curve of the qubit working frequency modulated by the DC signal on the magnetic flux line. This method requires testing the working frequency of a large number of qubits under the DC intensity of magnetic flux control, which requires a lot of time and resources. Summary of the invention

[0004] In view of this, the present invention proposes a method, device and equipment for calibrating the operating frequency of a quantum bit. Among them, the method for calibrating the operating frequency of a quantum bit proposed by the present invention adjusts the operating frequency of the quantum bit based on the gradient ascent method after determining that the decoherence time of the quantum bit at the operating frequency maximum point (i.e., SP point) has degraded, so that the operating frequency of the quantum bit returns to the operating frequency maximum point.

[0005] Based on the above purpose, one aspect of an embodiment of the present invention provides a method for calibrating the operating frequency of a quantum bit, the method comprising the following steps: setting the offset of the current applied signal strength of the quantum bit and the termination condition of the operating frequency calibration; in response to reaching the condition for calibrating the operating frequency of the quantum bit, calculating the offset operating frequency of the quantum bit under the offset, and obtaining the operating frequency change rate based on the offset operating frequency and the offset; iteratively updating the operating frequency change rate and the current applied signal strength by a gradient ascent method until the operating frequency change rate is less than the termination condition, thereby completing the adjustment of the operating frequency of the quantum bit to the operating frequency maximum value under the new applied signal strength.

[0006] In some embodiments, the method further includes: in response to detecting that the working performance of the quantum bit has decreased, obtaining the current decoherence time of the quantum bit and calculating the difference with the initial decoherence time corresponding to the maximum working frequency of the quantum bit under the current applied signal strength.

[0007] In some embodiments, the method further includes: setting a degradation time threshold corresponding to the initial decoherence time; and judging whether the conditions for calibrating the operating frequency of the quantum bit are met based on the difference and the degradation time threshold.

[0008] In some embodiments, judging whether the condition for calibrating the operating frequency of the quantum bit is met based on the difference and the size of the degradation time threshold corresponding to the initial decoherence time includes: in response to the difference being greater than the degradation time threshold, confirming that the condition for calibrating the operating frequency of the quantum bit is met.

[0009] In some embodiments, in response to meeting the condition for calibrating the operating frequency of the quantum bit, calculating the offset operating frequency of the quantum bit at the offset, and obtaining the operating frequency change rate based on the offset operating frequency and the offset includes: in response to meeting the condition for calibrating the operating frequency of the quantum bit, calculating the positive offset signal strength and the negative offset signal strength according to the offset, and obtaining the corresponding positive offset operating frequency and negative offset operating frequency based on the positive offset signal strength and the negative signal strength.

[0010] In some embodiments, the operating frequency change rate and the current applied signal strength are iteratively updated by the gradient ascent method until the operating frequency change rate is less than the termination condition, and completing the adjustment of the operating frequency of the quantum bit to the operating frequency maximum value under the new applied signal strength includes: updating the current applied signal strength according to the operating frequency change rate and the set learning rate.

[0011] In some embodiments, the operating frequency change rate and the current applied signal strength are iteratively updated by the gradient ascent method until the operating frequency change rate is less than the termination condition, and completing the adjustment of the operating frequency of the quantum bit to the operating frequency maximum value under the new applied signal strength also includes: iteratively updating the operating frequency change rate obtained by each update value of the current applied signal strength by the gradient ascent method until the operating frequency change rate is less than the termination condition.

[0012] In some embodiments, the termination condition is a preset value not greater than 10 -2 A positive number.

[0013] According to another aspect of an embodiment of the present invention, a device for calibrating the operating frequency of a quantum bit is provided, the device comprising: a first module, configured to set the offset of the current applied signal strength of the quantum bit and the termination condition of the operating frequency calibration; a second module, configured to calculate the offset operating frequency of the quantum bit under the offset in response to the condition for calibrating the operating frequency of the quantum bit being met, and obtain the operating frequency change rate based on the offset operating frequency and the offset; a third module, configured to iteratively update the operating frequency change rate and the current applied signal strength by a gradient ascent method until the operating frequency change rate is less than the termination condition, thereby completing the adjustment of the operating frequency of the quantum bit to the maximum operating frequency under the new applied signal strength.

[0014] In some embodiments, the device also includes a fourth module, configured to obtain the current decoherence time of the quantum bit in response to detecting a decrease in the working performance of the quantum bit and calculate the difference with the initial decoherence time corresponding to the maximum working frequency of the quantum bit under the current applied signal strength.

[0015] In some embodiments, the device also includes a fifth module, configured to set a degradation time threshold corresponding to the initial decoherence time; and determine whether the conditions for calibrating the operating frequency of the quantum bit are met based on the difference and the degradation time threshold.

[0016] In some embodiments, the fifth module is further configured to confirm that a condition for calibrating the operating frequency of the quantum bit is met in response to the difference being greater than the degradation time threshold.

[0017] In some embodiments, the second module is further configured to calculate the positive offset signal strength and the negative offset signal strength according to the offset in response to meeting the condition for calibrating the operating frequency of the quantum bit, and obtain the corresponding positive offset operating frequency and negative offset operating frequency based on the positive offset signal strength and the negative signal strength.

[0018] In some embodiments, the third module is further configured to update the current applied signal strength according to the operating frequency change rate and a set learning rate.

[0019] In some embodiments, the third module is further configured to iteratively update the operating frequency change rate obtained by each update value of the current applied signal strength through the gradient ascent method until the operating frequency change rate is less than the termination condition.

[0020] In some embodiments, the termination condition is a preset value not greater than 10 -2 A positive number.

[0021] Another aspect of an embodiment of the present invention provides a computer device, comprising at least one processor; and a memory, wherein the memory stores computer instructions executable on the processor, and the instructions implement the steps of any of the above methods when executed by the processor.

[0022] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is provided, which stores a computer program that implements any of the above method steps when executed by a processor.

[0023] The present invention has at least the following beneficial effects: The present invention proposes a method, device and equipment for calibrating the working frequency of a quantum bit, wherein the method for calibrating the working frequency of a quantum bit proposed by the present invention determines whether the quantum bit has currently deviated from the optimal working point according to the degree of degradation of the decoherence time of the quantum bit, and then adjusts the working frequency of the quantum bit that deviates from the optimal working point back to the optimal working point based on the gradient ascent method. The method proposed in the present application does not introduce additional control degrees of freedom, thereby reducing the influence of external electromagnetic noise on the quantum bit, and this calibration method does not require testing the working frequency of the quantum bit under a large number of flux-controlled DC intensities, thereby saving time and resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic diagram showing an embodiment of a method for calibrating a quantum bit operating frequency provided by the present invention;

[0026] Figure 2 The characteristic curve diagram of the quantum bit operating frequency provided by the present invention being regulated by the magnetic flux signal is shown;

[0027] Figure 3 A schematic diagram showing an embodiment of a device for calibrating a quantum bit operating frequency provided by the present invention is shown;

[0028] Figure 4 A schematic diagram showing an embodiment of a computer device provided by the present invention;

[0029] Figure 5 A schematic diagram showing an embodiment of a computer-readable storage medium provided by the present invention is shown. DETAILED DESCRIPTION

[0030] The following describes embodiments of the present invention. However, it should be understood that the disclosed embodiments are merely examples and other embodiments can take various alternative forms.

[0031] Furthermore, it should be noted that the terms "includes," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a series of elements includes not only those elements, but may also include elements not explicitly listed or inherent to these processes, methods, articles, or apparatuses.

[0032] One or more embodiments of the present application will be described below with reference to the accompanying drawings.

[0033] Based on the above objectives, a first aspect of an embodiment of the present invention provides an embodiment of a method for calibrating the operating frequency of a quantum bit. Figure 1 FIG. 1 is a schematic diagram of an embodiment of a method for calibrating the working frequency of a quantum bit provided by the present invention. Figure 1 As shown, a method for calibrating the quantum bit operating frequency according to an embodiment of the present invention includes performing the following steps at the server:

[0034] S1. Setting the offset of the current added signal strength of the quantum bit and the termination condition of the working frequency calibration;

[0035] S2. In response to reaching a condition for calibrating the operating frequency of the qubit, calculating the offset operating frequency of the qubit under the offset, and obtaining an operating frequency change rate based on the offset operating frequency and the offset;

[0036] S3. Iteratively update the operating frequency change rate and the current applied signal strength by using a gradient ascent method until the operating frequency change rate is less than the termination condition, thereby completing the adjustment of the operating frequency of the quantum bit to the maximum operating frequency under the new applied signal strength.

[0037] According to some embodiments of the present invention, the method also includes: in response to detecting that the working performance of the quantum bit has decreased, obtaining the current decoherence time of the quantum bit and calculating the difference with the initial decoherence time corresponding to the maximum working frequency of the quantum bit under the current applied signal strength.

[0038] According to several embodiments of the present invention, the method further includes: setting a degradation time threshold corresponding to the initial decoherence time; and judging whether the conditions for calibrating the working frequency of the quantum bit are met based on the difference and the degradation time threshold.

[0039] According to some embodiments of the present invention, judging whether the conditions for calibrating the operating frequency of the quantum bit are met based on the difference and the size of the degradation time threshold corresponding to the initial decoherence time includes: in response to the difference being greater than the degradation time threshold, confirming that the conditions for calibrating the operating frequency of the quantum bit are met.

[0040] According to several embodiments of the present invention, in response to the condition of calibrating the operating frequency of the quantum bit being met, the offset operating frequency of the quantum bit under the offset is calculated, and the operating frequency change rate is obtained based on the offset operating frequency and the offset, including: in response to the condition of calibrating the operating frequency of the quantum bit being met, the positive offset signal strength and the negative offset signal strength are calculated according to the offset, and the corresponding positive offset operating frequency and negative offset operating frequency are obtained based on the positive offset signal strength and the negative offset signal strength.

[0041] According to several embodiments of the present invention, the operating frequency change rate and the current applied signal strength are iteratively updated by the gradient ascent method until the operating frequency change rate is less than the termination condition, and the operating frequency of the quantum bit is adjusted to the maximum operating frequency under the new applied signal strength, including: updating the current applied signal strength according to the operating frequency change rate and the set learning rate.

[0042] According to some embodiments of the present invention, the operating frequency change rate and the current applied signal strength are iteratively updated by the gradient ascent method until the operating frequency change rate is less than the termination condition, and completing the adjustment of the operating frequency of the quantum bit to the operating frequency maximum value under the new applied signal strength also includes: iteratively updating the operating frequency change rate obtained by each update value of the current applied signal strength by the gradient ascent method until the operating frequency change rate is less than the termination condition.

[0043] According to some embodiments of the present invention, the termination condition is a preset value not greater than 10 -2 A positive number.

[0044] The following is another embodiment of a method for calibrating the operating frequency of a quantum bit provided by the present invention.

[0045] Figure 2 The characteristic curve diagram of the quantum bit operating frequency provided by the present invention being adjusted by the magnetic flux signal is shown in FIG. Figure 2 As shown, in this embodiment, the de-correlation time corresponding to the maximum value of the working frequency of the qubit (i.e., the SP point) under the condition that the DC signal strength on the magnetic flux control line is A is T1. After the qubit has worked for a period of time, when it is detected that the working performance of the qubit has decreased, it is necessary to determine whether the working frequency of the qubit needs to be calibrated and how to calibrate it. The decoherence time of the qubit is calibrated and compared with the decoherence time of the qubit that previously worked at the SP point. When the degradation time of the current decoherence time reaches a certain degree, it is considered that the working frequency of the qubit at the SP point has shifted to a certain extent, and the working frequency of the qubit needs to be adjusted.

[0046] The degradation threshold δ of the decoherence time of the quantum bit at the SP point, the learning rate φ (φ is a positive number), the offset a and the termination condition ρ (ρ is a positive number close to 0) are preset, and the DC signal strength on the current flux control line is A.

[0047] When the working performance of the qubit is detected to be degraded, the current decoherence time of the qubit is calibrated, and the measured result is T2, and the relationship between the difference between T1 and T2 and the degradation threshold δ is determined. If the difference between T1 and T2 is less than the degradation threshold δ, it means that the working frequency of the qubit does not need to be calibrated at this time; if the difference between T1 and T2 is greater than the degradation threshold δ, it means that the working frequency of the qubit needs to be calibrated at this time.

[0048] If the working frequency of the quantum bit needs to be calibrated, first adjust the DC signal strength on the flux control line to A+a, and calibrate the working frequency f+ corresponding to the quantum bit at this time; then adjust the DC signal strength on the flux control line to Aa, and calibrate the working frequency f- corresponding to the quantum bit at this time. The slope of the DC signal strength point A is calculated by the working frequency f+ corresponding to the DC signal strength A+a and the working frequency f- corresponding to the DC signal strength Aa (f+-f-) / (2a), that is, the rate of change of the working frequency at the point where the DC signal strength is A is (f+-f-) / (2a), and the DC signal strength is updated according to the change rate and the set learning rate, that is, updated to:

[0049]

[0050] Repeat the above steps until the change rate (f+-f-) / (2a) is less than the termination condition ρ, which means that the calibration of the quantum bit operating frequency is completed, and the quantum bit operating frequency returns to the maximum operating frequency position corresponding to the SP point.

[0051] According to a second aspect of an embodiment of the present invention, a device for calibrating the operating frequency of a quantum bit is proposed. Figure 3 FIG. 1 is a schematic diagram of an embodiment of a device for calibrating the working frequency of a quantum bit provided by the present invention. Figure 3 As shown, a device for calibrating the working frequency of a quantum bit provided by the present invention includes: a first module 011, configured to set the offset of the current applied signal strength of the quantum bit and the termination condition of the working frequency calibration; a second module 012, configured to calculate the offset working frequency of the quantum bit under the offset in response to the condition of calibrating the working frequency of the quantum bit, and obtain the working frequency change rate based on the offset working frequency and the offset; a third module 013, configured to iteratively update the working frequency change rate and the current applied signal strength by a gradient ascent method until the working frequency change rate is less than the termination condition, thereby completing the adjustment of the working frequency of the quantum bit to the maximum working frequency under the new applied signal strength.

[0052] According to some embodiments of the present invention, the device also includes a fourth module, which is configured to obtain the current decoherence time of the quantum bit in response to detecting that the working performance of the quantum bit has decreased, and calculate the difference with the initial decoherence time corresponding to the maximum working frequency of the quantum bit under the current applied signal strength.

[0053] According to some embodiments of the present invention, the device also includes a fifth module, which is configured to set a degradation time threshold corresponding to the initial decoherence time; and determine whether the conditions for calibrating the operating frequency of the quantum bit are met based on the size of the difference and the degradation time threshold.

[0054] According to some embodiments of the present invention, the fifth module is further configured to confirm that a condition for calibrating the operating frequency of the quantum bit is met in response to the difference being greater than the degradation time threshold.

[0055] According to some embodiments of the present invention, the second module is further configured to calculate the positive offset signal strength and the negative offset signal strength according to the offset in response to meeting the condition for calibrating the operating frequency of the quantum bit, and obtain the corresponding positive offset operating frequency and negative offset operating frequency based on the positive offset signal strength and the negative offset signal strength.

[0056] According to some embodiments of the present invention, the third module is further configured to update the current applied signal strength according to the operating frequency change rate and a set learning rate.

[0057] According to some embodiments of the present invention, the third module is further configured to iteratively update the operating frequency change rate obtained by each update value of the current applied signal strength through the gradient ascent method until the operating frequency change rate is less than the termination condition.

[0058] According to some embodiments of the present invention, the termination condition is a preset value not greater than 10 -2 A positive number.

[0059] Based on the above objectives, a third aspect of an embodiment of the present invention provides a computer device, Figure 4 FIG. 2 is a schematic diagram of an embodiment of a computer device provided by the present invention. Figure 4 As shown, an embodiment of a computer device provided by the present invention includes the following modules: at least one processor 021; and a memory 022, the memory 022 stores computer instructions 023 that can be run on the processor 021, and the computer instructions 023 are executed by the processor 021 to implement the steps of the method as described above, wherein the method for executing the steps includes: setting the offset of the current applied signal strength of the quantum bit and the termination condition of the operating frequency calibration; in response to reaching the condition for calibrating the operating frequency of the quantum bit, calculating the offset operating frequency of the quantum bit under the offset, and obtaining the operating frequency change rate based on the offset operating frequency and the offset; iteratively updating the operating frequency change rate and the current applied signal strength by the gradient ascent method until the operating frequency change rate is less than the termination condition, thereby completing the adjustment of the operating frequency of the quantum bit to the maximum operating frequency under the new applied signal strength.

[0060] According to some embodiments of the present invention, the method also includes: in response to detecting that the working performance of the quantum bit has decreased, obtaining the current decoherence time of the quantum bit and calculating the difference with the initial decoherence time corresponding to the maximum working frequency of the quantum bit under the current applied signal strength.

[0061] According to several embodiments of the present invention, the method further includes: setting a degradation time threshold corresponding to the initial decoherence time; and judging whether the conditions for calibrating the working frequency of the quantum bit are met based on the difference and the degradation time threshold.

[0062] According to some embodiments of the present invention, judging whether the conditions for calibrating the operating frequency of the quantum bit are met based on the difference and the size of the degradation time threshold corresponding to the initial decoherence time includes: in response to the difference being greater than the degradation time threshold, confirming that the conditions for calibrating the operating frequency of the quantum bit are met.

[0063] According to several embodiments of the present invention, in response to the condition of calibrating the operating frequency of the quantum bit being met, the offset operating frequency of the quantum bit under the offset is calculated, and the operating frequency change rate is obtained based on the offset operating frequency and the offset, including: in response to the condition of calibrating the operating frequency of the quantum bit being met, the positive offset signal strength and the negative offset signal strength are calculated according to the offset, and the corresponding positive offset operating frequency and negative offset operating frequency are obtained based on the positive offset signal strength and the negative offset signal strength.

[0064] According to several embodiments of the present invention, the operating frequency change rate and the current applied signal strength are iteratively updated by the gradient ascent method until the operating frequency change rate is less than the termination condition, and the operating frequency of the quantum bit is adjusted to the maximum operating frequency under the new applied signal strength, including: updating the current applied signal strength according to the operating frequency change rate and the set learning rate.

[0065] According to some embodiments of the present invention, the operating frequency change rate and the current applied signal strength are iteratively updated by the gradient ascent method until the operating frequency change rate is less than the termination condition, and completing the adjustment of the operating frequency of the quantum bit to the operating frequency maximum value under the new applied signal strength also includes: iteratively updating the operating frequency change rate obtained by each update value of the current applied signal strength by the gradient ascent method until the operating frequency change rate is less than the termination condition.

[0066] According to some embodiments of the present invention, the termination condition is a preset value not greater than 10 -2 A positive number.

[0067] The present invention also provides a computer-readable storage medium. Figure 5 FIG. 2 is a schematic diagram of an embodiment of a computer-readable storage medium provided by the present invention. Figure 5 As shown, the computer readable storage medium 031 stores a computer program 032 that performs the following steps when executed by a processor.

[0068] Finally, it should be noted that a person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program of the method for setting system parameters can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium of the program can be a disk, an optical disk, a read-only storage memory (ROM) or a random access memory (RAM), etc. The above-mentioned computer program embodiments can achieve the same or similar effects as the corresponding above-mentioned arbitrary method embodiments.

[0069] In addition, the method disclosed in the embodiment of the present invention can also be implemented as a computer program executed by a processor, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the above functions defined in the method disclosed in the embodiment of the present invention are performed.

[0070] In addition, the above method steps and system units may also be implemented using a controller and a computer-readable storage medium for storing a computer program that enables the controller to implement the above steps or unit functions.

[0071] It will also be appreciated by those skilled in the art that various exemplary logic blocks, modules, circuits and algorithm steps described in conjunction with the disclosure herein can be implemented as electronic hardware, computer software or a combination of the two. In order to clearly illustrate this interchangeability of hardware and software, a general description has been given to the functions of various schematic components, blocks, modules, circuits and steps. Whether this function is implemented as software or hardware depends on specific applications and the design constraints imposed on the entire system. Those skilled in the art can implement the function in various ways for each specific application, but this implementation decision should not be interpreted as causing a departure from the disclosed scope of the embodiments of the present invention.

[0072] In one or more exemplary designs, the function can be implemented in hardware, software, firmware or any combination thereof. If implemented in software, the function can be stored on a computer-readable medium or transmitted by a computer-readable medium as one or more instructions or codes. Computer-readable media include computer storage media and communication media, and the communication media include any media that helps to transmit a computer program from one location to another. The storage medium can be any available medium that can be accessed by a general or special computer. As an example and not limiting, the computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other medium that can be used to carry or store the required program code in the form of an instruction or data structure and can be accessed by a general or special computer or a general or special processor. In addition, any connection can be appropriately referred to as a computer-readable medium. For example, if a coaxial cable, optical fiber cable, twisted pair, digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwaves are used to send software from a website, server or other remote source, the above-mentioned coaxial cable, optical fiber cable, twisted pair, DOL or wireless technologies such as infrared, radio and microwaves are all included in the definition of the medium. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, Blu-ray disc, wherein disks usually reproduce data magnetically, while optical discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0073] The above are exemplary embodiments disclosed in the present invention, but it should be noted that various changes and modifications may be made without departing from the scope disclosed in the embodiments of the present invention as defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

[0074] It should be understood that, as used herein, the singular forms "a", "an" are intended to include the plural forms as well, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations including one or more of the associated listed items.

[0075] The serial numbers of the embodiments disclosed in the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0076] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0077] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for calibrating the operating frequency of a quantum bit, characterized in that: include: Set the offset of the current added signal strength of the quantum bit and the termination condition of the working frequency calibration; In response to reaching a condition for calibrating the operating frequency of the qubit, calculating the offset operating frequency of the qubit at the offset, and obtaining an operating frequency change rate based on the offset operating frequency and the offset; Iteratively updating the operating frequency change rate and the current applied signal strength by a gradient ascent method until the operating frequency change rate is less than the termination condition, thereby completing the adjustment of the operating frequency of the quantum bit to the maximum operating frequency under the new applied signal strength; In response to detecting that the working performance of the qubit has decreased, obtaining a current decoherence time of the qubit and calculating a difference with an initial decoherence time corresponding to a maximum working frequency of the qubit at the current applied signal strength; Setting a degradation time threshold corresponding to the initial decoherence time; Determining whether a condition for calibrating the operating frequency of the quantum bit is met according to the difference and the degradation time threshold; The determining whether the condition for calibrating the operating frequency of the quantum bit is met according to the difference and the degeneration time threshold corresponding to the initial decoherence time includes: In response to the difference being greater than the degradation time threshold, it is confirmed that a condition for calibrating the operating frequency of the quantum bit is met.

2. The method according to claim 1, characterized in that In response to reaching a condition for calibrating the operating frequency of the quantum bit, calculating the offset operating frequency of the quantum bit under the offset, and obtaining the operating frequency change rate based on the offset operating frequency and the offset includes: In response to reaching a condition for calibrating the operating frequency of the quantum bit, a positive offset signal strength and a negative offset signal strength are calculated according to the offset, and a corresponding positive offset operating frequency and a negative offset operating frequency are obtained based on the positive offset signal strength and the negative offset signal strength.

3. The method according to claim 1, characterized in that The iterative updating of the operating frequency change rate and the current applied signal strength by the gradient ascent method until the operating frequency change rate is less than the termination condition, and completing the adjustment of the operating frequency of the quantum bit to the maximum operating frequency under the new applied signal strength includes: The currently applied signal strength is updated according to the operating frequency change rate and the set learning rate.

4. The method according to claim 3, characterized in that The iterative updating of the operating frequency change rate and the current applied signal strength by the gradient ascent method until the operating frequency change rate is less than the termination condition, and completing the adjustment of the operating frequency of the quantum bit to the maximum operating frequency under the new applied signal strength also includes: The operating frequency change rate obtained by each updated value of the current applied signal strength is iteratively updated by the gradient ascent method until the operating frequency change rate is less than the termination condition.

5. The method according to claim 1, characterized in that The termination condition is a preset value of no more than 10 -2 A positive number.

6. A device for calibrating the working frequency of a quantum bit, characterized in that: The device comprises: The first module is configured to set the offset of the current applied signal strength of the quantum bit and the termination condition of the working frequency calibration; A second module is configured to calculate the offset operating frequency of the qubit under the offset in response to reaching a condition for calibrating the operating frequency of the qubit, and obtain an operating frequency change rate based on the offset operating frequency and the offset; The third module is configured to iteratively update the operating frequency change rate and the current added signal strength by a gradient ascent method until the operating frequency change rate is less than the termination condition, thereby completing the adjustment of the operating frequency of the quantum bit to the maximum operating frequency under the new added signal strength; And modules that perform the following functions: In response to detecting that the working performance of the qubit has decreased, obtaining a current decoherence time of the qubit and calculating a difference with an initial decoherence time corresponding to a maximum working frequency of the qubit at the current applied signal strength; Setting a degradation time threshold corresponding to the initial decoherence time; Determining whether a condition for calibrating the operating frequency of the quantum bit is met according to the difference and the degradation time threshold; In response to the difference being greater than the degradation time threshold, it is confirmed that a condition for calibrating the operating frequency of the quantum bit is met.

7. A computer device, characterized in that: include: at least one processor; as well as A memory storing computer instructions executable on the processor, wherein the instructions, when executed by the processor, implement the steps of the method according to any one of claims 1 to 5.

Images