WO2024041361A1

WO2024041361A1 - Test characterization method and apparatus for adjustable coupler of quantum chip, and quantum computer

Info

Publication number: WO2024041361A1
Application number: PCT/CN2023/111508
Authority: WO
Inventors: 邓星; 孔伟成
Original assignee: 本源量子计算科技（合肥）股份有限公司
Priority date: 2022-08-22
Filing date: 2023-08-07
Publication date: 2024-02-29
Also published as: CN115470923A; CN115470923B; WO2024041361A9

Abstract

A test characterization method and apparatus for an adjustable coupler of a quantum chip, and a quantum computer. The method comprises: firstly carrying out a first experiment on an adjustable coupler and a first quantum bit, the first experiment being used for acquiring the change condition of a first amplitude of the first quantum bit along with a direct-current (DC) voltage and the frequency of a control signal, wherein the adjustable coupler is coupled to the first quantum bit, the first amplitude is an amplitude of a first signal carrying quantum state information in a reading cavity of the first quantum bit, the DC voltage is a DC working voltage of the adjustable coupler, and the control signal is a signal for adjusting a quantum state of the first quantum bit; and then acquiring a DC spectrum of the adjustable coupler on the basis of the change condition. On the basis of the solution of the present application, the DC spectrum of the adjustable coupler can be indirectly acquired by cooperating with the quantum bit coupled to the adjustable coupler, thereby completing the test characterization of performance parameters of a quantum chip, and filling the technical gap.

Description

Quantum chip adjustable coupler test characterization method, device, quantum computer

This application claims the priority of the Chinese patent application filed with the China Patent Office on August 22, 2022, with the application number 202211007594. The contents are incorporated into this application by reference.

Technical field

The present application relates to the field of quantum computing technology, and in particular to a quantum chip adjustable coupler test characterization method, device, and quantum computer.

Background technique

Quantum computing and quantum information is an interdisciplinary subject that implements computing and information processing tasks based on the principles of quantum mechanics. It is closely related to quantum physics, computer science, information science and other disciplines. There has been rapid development in the past two decades. Quantum algorithms based on quantum computers in scenarios such as factorization and unstructured search have demonstrated performance that far exceeds existing algorithms based on classical computers, and this direction has also placed expectations on surpassing existing computing capabilities. Since quantum computing has the potential to far exceed the performance of classical computers in solving specific problems, in order to realize a quantum computer, it is necessary to obtain a quantum chip containing a sufficient number and quality of qubits, and to be able to perform extremely high fidelity on the qubits. Quantum logic gate operation and reading. Quantum chips are to quantum computers what CPUs are to traditional computers. Quantum chips are the core components of quantum computers, and quantum chips are processors that perform quantum calculations. Before each quantum chip is officially put into use, the relevant parameters of the qubits in the quantum chip need to be tested and characterized.

In the qubit expansion architecture based on adjustable couplers, coupling between two qubits can be achieved through a fixed capacitive coupling and an adjustable coupler that can adjust the coupling coefficient. The adjustable coupler has a similar structure to the qubit. However, since the tunable coupler does not have a resonant cavity that can directly read information, the frequency of the tunable coupler cannot be directly obtained when testing and characterizing the performance parameters of the quantum chip, which leads to the DC ( Direct Current (DC) spectrum or AC (Alternating Current, AC) spectrum cannot be obtained.

Therefore, how to test and characterize adjustable couplers has become an urgent problem in this field.

It should be noted that the information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or any form of implication that the information constitutes what is already known to those skilled in the art. current technology.

Contents of the invention

The purpose of this application is to provide a quantum chip adjustable coupler test and characterization method, device, and quantum computer to solve the problem in the prior art that the adjustable coupler cannot be tested and characterized.

In order to solve the above technical problems, this application proposes a quantum chip adjustable coupler test and characterization method, including:

A first experiment is performed on the tunable coupler and the first qubit, and the first experiment is used to obtain the variation of the first amplitude of the first qubit with the DC voltage and the frequency of the control signal, wherein, The adjustable coupler is coupled to the first qubit, the first amplitude is the amplitude of the first signal carrying quantum state information in the reading cavity of the first qubit, and the DC voltage is the The DC operating voltage of the adjustable coupler, the control signal is a signal used to adjust the quantum state of the first qubit;

The DC spectrum of the adjustable coupler is obtained based on the change.

Optionally, performing a first experiment on the tunable coupler and the first qubit includes:

Configuring the traversal range of the DC voltage as a first range;

Configuring the traversal range of the frequency of the control signal to be a second range;

Traverse the DC voltage within the first range, and traverse the frequency of the control signal applied to the first qubit within the second range each time the DC voltage is traversed;

Obtain the change of the first amplitude of the first qubit with the DC voltage and the frequency of the control signal.

Optionally, the DC voltage is traversed according to a first step in the first range, wherein the first step is preconfigured.

Optionally, the frequency of the control signal is traversed in the second range according to a second step size, wherein the second step size is preconfigured.

Optionally, obtaining the DC spectrum of the adjustable coupler based on the change includes:

Obtain coordinate information of several points located at the energy level split based on the change, where the coordinate information includes the value of the DC voltage and the corresponding value of the frequency of the control signal;

The DC spectrum of the adjustable coupler is obtained based on the coordinate information.

Optionally, obtaining the DC spectrum of the adjustable coupler based on the coordinate information includes:

Perform fitting processing on the data contained in the coordinate information to obtain the DC spectrum of the adjustable coupler.

Optionally, the data contained in the coordinate information is fitted according to the following fitting function:

Where, x is the DC voltage, y is the frequency of the control signal, and A, B, d, m, and δ are parameters of the fitting function.

Based on the same inventive concept, this application also proposes a quantum chip adjustable coupler test and characterization device, including:

A first experiment execution unit configured to perform a first experiment on the tunable coupler and the first qubit, the first experiment being used to obtain the first amplitude of the first qubit as a function of the DC voltage and the control signal changes in frequency, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the first signal carrying quantum state information in the reading cavity of the first qubit. The amplitude of the DC voltage is the DC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

A spectrum acquisition unit configured to acquire the DC spectrum of the adjustable coupler based on the changing conditions.

Based on the same inventive concept, this application also proposes a quantum chip adjustable coupler test and characterization method, including:

A first experiment is performed on the tunable coupler and the first qubit, and the first experiment is used to obtain the variation of the first amplitude of the first qubit with the AC voltage and the frequency of the control signal, wherein, The adjustable coupler is coupled to the first qubit, the first amplitude is the amplitude of the first signal carrying quantum state information in the reading cavity of the first qubit, and the AC voltage is the The AC operating voltage of the adjustable coupler, the control signal is a signal used to adjust the quantum state of the first qubit;

The AC spectrum of the adjustable coupler is obtained based on the change.

A first experiment execution unit configured to perform a first experiment on the tunable coupler and the first qubit, the first experiment being used to obtain the first amplitude of the first qubit as a function of the AC voltage and the control signal changes in frequency, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the first amplitude of the quantum state information carried in the reading cavity of the first qubit. The amplitude of the signal, the AC voltage is the AC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

A spectrum acquisition unit configured to acquire the AC spectrum of the adjustable coupler based on the changing conditions.

Based on the same inventive concept, this application also proposes a quantum control system that utilizes the quantum chip tunable coupler test characterization method described in any of the above characterizations, or includes the quantum chip tunable coupling described in the above characterizations. Device testing and characterization equipment.

Based on the same inventive concept, this application also proposes a quantum computer, including the quantum control system described in the above description.

Based on the same inventive concept, this application also proposes a readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it can realize the adjustable coupling of the quantum chip described in any one of the above descriptions. Device test characterization methods.

Based on the same inventive concept, this application also proposes a computer program product containing instructions that, when run on a computer, causes the computer to execute the quantum chip adjustable coupler test characterization method described in any one of the above descriptions.

Compared with the existing technology, this application has the following beneficial effects:

The quantum chip tunable coupler testing and characterization method proposed in this application first performs a first experiment on the tunable coupler and the first qubit. The first experiment is used to obtain the first amplitude of the first qubit over time. Changes in DC voltage and frequency of the control signal, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the quantum state carried in the reading cavity of the first qubit. The amplitude of the first signal of information, the DC voltage is the DC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit; then based on the change Situation Obtain the DC spectrum of the adjustable coupler. Based on the solution of this application, the DC spectrum of the adjustable coupler can be indirectly obtained through the cooperation of the qubits coupled to the adjustable coupler, thereby completing the test and characterization of the performance parameters of the quantum chip, filling the technical gap.

This application also proposes a quantum chip adjustable coupler test and characterization device, a quantum control system, a quantum computer and a readable storage medium, which belong to the same inventive concept as the quantum chip adjustable coupler test and characterization method, and therefore have the same The beneficial effects will not be described in detail here.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present application, and constitute a part of the present application. However, the illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation of the present application.

Figure 1 is a schematic flow chart of a quantum chip adjustable coupler test and characterization method proposed by this application;

Figure 2 is a schematic diagram 1 of the results obtained after performing the first experiment on the adjustable coupler and the first qubit in an embodiment;

Figure 3 is a schematic diagram 2 of the results obtained after performing the first experiment on the adjustable coupler and the first qubit in an embodiment;

Figure 4 is a schematic diagram of the DC spectrum obtained after fitting the results of the first experiment;

Figure 5 is a schematic structural diagram of a quantum chip adjustable coupler test and characterization device proposed in an embodiment of the present application;

Figure 6 is a schematic flow chart of a quantum chip adjustable coupler test and characterization method proposed in an embodiment of the present application;

Figure 7 is a schematic structural diagram of a quantum chip adjustable coupler test and characterization device proposed in an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solutions, and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and examples. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art fall within the scope of protection of this application.

In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings. , is only for the convenience of describing the present application and simplifying the description, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present application.

In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

Please refer to Figure 1. This embodiment of the present application proposes a test and characterization method for a quantum chip adjustable coupler, including:

S10: Perform a first experiment on the adjustable coupler and the first qubit, the first experiment is used to obtain the change of the first amplitude of the first qubit with the DC voltage and the frequency of the control signal, wherein, The adjustable coupler is coupled to the first qubit, the first amplitude is the amplitude of the first signal carrying quantum state information in the reading cavity of the first qubit, and the DC voltage is the DC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

S20: Obtain the DC spectrum of the adjustable coupler based on the change.

The difference from the existing technology is that the quantum chip tunable coupler testing and characterization method proposed in the embodiment of this application first performs a first experiment on the tunable coupler and the first qubit, and the first experiment is used to obtain the The first amplitude of the first qubit changes with the frequency of the DC voltage and the control signal, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the change of the first qubit. The amplitude of the first signal carrying quantum state information in the reading cavity of a qubit, the DC voltage is the DC operating voltage of the adjustable coupler, and the control signal is used to adjust the first qubit The signal of the quantum state; and then obtain the DC spectrum of the adjustable coupler based on the change. Based on the solution of this application, the DC spectrum of the adjustable coupler can be indirectly obtained through the cooperation of the qubits coupled to the adjustable coupler, thereby completing the test and characterization of the performance parameters of the quantum chip, filling the technical gap.

The experimental results of the first experiment can be referred to Figures 2 and 3. Figures 2 and 3 are the results obtained after performing the first experiment on the adjustable coupler and the first qubit in a certain embodiment. Figures 2 and Figure 3 are three-dimensional diagrams. The abscissa is the DC voltage, and the ordinate is the frequency of the control signal. The changes in color represent different amplitude changes. The amplitude here is the reading of the first qubit. The amplitude of the signal carrying quantum state information in the cavity.

A qubit and an adjustable coupler can form a three-level system. The three-level system includes three basis vectors |00>, |01> and |10>, where |αβ> represents the qubit occupation as |α> and the adjustable coupler occupy |β>. In the three-level system, applying a periodic drive to the qubit can couple |00> and |10>. In addition, the coupling strength between |01> and |10> is g. The frequencies of these three energy levels are ω ₀₀ , ω ₁₀ and ω ₀₁ respectively. Here ω ₀₀ =0, ω ₁₀ =f ₁₀ , ω ₀₁ =f ₀₁ , Among them, f ₁₀ is the frequency of the qubit, and f ₀₁ is the frequency of the adjustable coupler.

The Hamiltonian composed of |10> and |01> subspaces is:

The two eigenstates of the three-level system are:

The corresponding two eigenvalues are:

Among them, Δ=ω ₀₁ -ω ₁₀ , when the energy between |01> and |10> is equal, Δ=0, that is, the resonance state of the qubit and the adjustable coupler, at this time When ω=ω ₁₀ , the three-level system cannot be excited from |00> to |10>, and when ω=E _+(-) =ω ₁₀ +(-)g, the three-level system can be excited by |00> is excited to |+>(|—>) respectively; when the energy between |01> and |10> is far detuned, that is, the qubit and the adjustable coupler are in a non-resonant state, such as Δ>>0, Then |φ> ₊ ≈|10>,|φ> _- ≈|01>), then the three-level system can be excited from |00> to |10> through ω=ω ₁₀ -g ² /Δ. ω represents the frequency of the control signal of the quantum state of the qubit.

Based on the above description, it can be seen that when the frequency of the qubit and the adjustable coupler does not resonate, if the qubit is excited, there can only be one excitation frequency (that is, the frequency of the control signal of the quantum state of the qubit), ω = ω ₁₀ - g ² /Δ can excite the qubit. The essential reason is that only one of the corresponding eigenstates contains a large |10>, so at this time, no energy level splitting can be observed in the experimental results of the first experiment. cracking phenomenon. When the frequency of the qubit and the adjustable coupler are equal, that is, when resonance occurs, the qubit is excited at this time. Bit excitation can be achieved at different excitation frequencies, so it can be observed in the experimental results of the first experiment There is an energy level splitting phenomenon, the essence of which is that both eigenstates contain larger |10>. The area in the dotted box in Figure 2 and Figure 3 is the area where energy level splitting occurs. At several points in this area, the frequency of the qubit is equal to the frequency of the adjustable coupler. Using this This principle can indirectly obtain the frequency of the adjustable coupler and the corresponding DC voltage.

In this embodiment, the first experiment is performed on the tunable coupler and the first qubit, including:

Configuring the traversal range of the DC voltage as a first range;

For example, you can select a value in the first range (that is, the voltage value, which can be called the first voltage value), and then select a value in the second range (that is, the frequency value, which can be called the first frequency value), and then , apply a DC voltage to the adjustable coupler according to the first voltage value, and apply a control signal to the first qubit according to the first frequency value, and then obtain the signal carrying quantum state information in the reading cavity of the first qubit at this time. amplitude.

You can also select a different value in the second range (which can be called a second frequency value), apply a DC voltage to the adjustable coupler according to the first voltage value, and apply control to the first qubit according to the second frequency value. signal, and further, the amplitude of the signal carrying quantum state information in the reading cavity of the first qubit at this time is obtained.

After the frequency values in the second range are traversed, a different voltage value can be selected, and according to the above logic, the frequency values in the second range are traversed again to obtain the first qubit's reading cavity carrying quantum state information. The amplitude of the signal.

In this way, the amplitude of the signal carrying quantum state information in the reading cavity of the first qubit under different DC voltages and different frequency control signals can be obtained. That is, it can be obtained that the amplitude of the signal carrying quantum state information in the reading cavity of the first qubit changes as the DC voltage of the adjustable coupler and the frequency of the control signal change.

Specifically, in this embodiment, the DC voltage is traversed in the first range according to a first step, wherein the first step is preconfigured. In addition, the frequency of the control signal is traversed in the second range according to a second step size, wherein the second step size is preconfigured.

Specifically, in the embodiment of the present application, obtaining the DC spectrum of the adjustable coupler based on the change includes:

Based on the changes, the coordinate information of several points located at the energy level splitting point is obtained. The target information includes the value of the DC voltage and the corresponding value of the frequency of the control signal;

Please refer to Figures 2 to 4. Several coordinates in area A and area B in Figure 4 are obtained from the energy level splitting points in Figures 2 and 3. Among them, based on the energy level splitting point in Figure 2, the A region of Figure 4 can be obtained, and based on the energy level splitting point in Figure 3, the B region of Figure 4 can be obtained. After obtaining these coordinates, further, obtaining the DC spectrum of the adjustable coupler based on the coordinate information includes:

In this embodiment, after obtaining several coordinate information from the energy level splitting points in Figures 2 and 3, these coordinate information are fitted and the curve of the entire DC spectrum can be fitted. For details, please refer to Figure 4.

Furthermore, in order to more accurately fit the DC spectrum of the adjustable coupler, the applicant proposed to fit the coordinate information through a fitting function. Specifically, to fit the coordinate information contained in the coordinate information The data is fitted according to the following fitting function:

For example, you can obtain multiple DC voltages at the energy level splitting point and the frequency of the corresponding control signal. Then, substitute the obtained data into the above fitting function to obtain multiple DC voltages containing A, B, d, m, δ. By using the equation of the parameters, the specific values of the parameters A, B, d, m, and δ can be solved, and then the curve represented by the fitting function can be determined, that is, the DC spectrum of the adjustable coupler can be obtained.

Based on the same inventive concept, please refer to Figure 5. The embodiment of the present application also proposes a quantum chip adjustable coupler test and characterization device, including:

A first experiment execution unit 10 configured to perform a first experiment on the tunable coupler and the first qubit, the first experiment being used to obtain the first amplitude of the first qubit as a function of DC voltage and control Changes in the frequency of the signal, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the first amplitude of the quantum state information carried in the reading cavity of the first qubit. The amplitude of the signal, the DC voltage is the DC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

Spectrum acquisition unit 20 is configured to acquire the DC spectrum of the adjustable coupler based on the changing conditions.

It can be understood that the first experiment execution unit 10 and the spectrum acquisition unit 20 can be combined and implemented in one device, or any one of the modules can be split into multiple sub-modules, or the first experiment At least part of the functions of one or more modules in the execution unit 10 and the spectrum acquisition unit 20 may be combined with at least part of the functions of other modules and implemented in one functional module. According to embodiments of the present application, at least one of the first experiment execution unit 10 and the spectrum acquisition unit 20 may be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), system on a chip, system on a substrate, system on a package, application specific integrated circuit (ASIC), or any other reasonable way to integrate or package circuits, such as hardware or firmware, or in software, This is achieved by an appropriate combination of hardware and firmware implementation methods. Alternatively, at least one of the first experiment execution unit 10 and the spectrum acquisition unit 20 may be at least partially implemented as a computer program module, and when the program is run by a computer, the functions of the corresponding modules may be executed.

Based on the same inventive concept, please refer to Figure 6. The embodiment of this application also proposes a quantum chip adjustable coupler test and characterization method, including:

S100: Perform a first experiment on the adjustable coupler and the first qubit, the first experiment is used to obtain the change of the first amplitude of the first qubit with the AC voltage and the frequency of the control signal, wherein, The adjustable coupler is coupled to the first qubit, the first amplitude is the amplitude of the first signal carrying quantum state information in the reading cavity of the first qubit, and the AC voltage is the AC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

S200: Obtain the AC spectrum of the adjustable coupler based on the change.

Similar to the way of acquiring the DC spectrum of the adjustable coupler in the above embodiment, when acquiring the AC spectrum, the first qubit can also be obtained by configuring the traversal range of the AC voltage and the traversal range of the frequency of the control signal. The change of the first amplitude value with the AC voltage and the frequency of the control signal.

In the same way, the coordinate information of several points located at the energy level splitting can be obtained according to the changes, and the AC spectrum of the tunable coupler can be obtained. Similarly, during processing, the coordinate information can also be fitted according to the fitting function in the above embodiment to obtain the AC spectrum.

Based on the same inventive concept, please refer to Figure 7. The embodiment of the present application also proposes a quantum chip adjustable coupler test and characterization device, including:

A first experiment execution unit 100 configured to perform a first experiment on the tunable coupler and the first qubit, the first experiment being used to obtain the first amplitude of the first qubit as a function of AC voltage and control Changes in the frequency of the signal, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the first amplitude of the quantum state information carried in the reading cavity of the first qubit. The amplitude of the signal, the AC voltage is the AC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

Spectrum acquisition unit 200 is configured to acquire the AC spectrum of the adjustable coupler based on the changing conditions.

It can be understood that the first experiment execution unit 100 and the spectrum acquisition unit 200 can be combined and implemented in one device, or any one of the modules can be split into multiple sub-modules, or the first experiment At least part of the functions of one or more modules in the execution unit 100 and the spectrum acquisition unit 200 may be combined with at least part of the functions of other modules and implemented in one functional module. According to embodiments of the present application, at least one of the first experiment execution unit 100 and the spectrum acquisition unit 200 may be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), system on a chip, system on a substrate, system on a package, application specific integrated circuit (ASIC), or any other reasonable way to integrate or package circuits, such as hardware or firmware, or in software, This is achieved by an appropriate combination of hardware and firmware implementation methods. Alternatively, at least one of the first experiment execution unit 100 and the spectrum acquisition unit 200 may be at least partially implemented as a computer program module, and when the program is run by a computer, the functions of the corresponding modules may be executed.

Based on the same inventive concept, embodiments of the present application also propose a quantum control system that utilizes the quantum chip adjustable coupler test characterization method described in any of the above descriptions, or includes the quantum chip adjustable coupler described in the above descriptions. Adjustable coupler test characterization device.

Based on the same inventive concept, embodiments of the present application also provide a quantum computer, including the quantum control system described in the above description.

Based on the same inventive concept, embodiments of the present application also propose a readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it can realize the quantum chip described in any of the above descriptions. Adjustable coupler test characterization methods.

Based on the same inventive concept, embodiments of the present application also propose a computer program product containing instructions, which when run on a computer causes the computer to execute the quantum chip adjustable coupler test characterization method described in any one of the above descriptions. .

The readable storage medium may be a tangible device that can hold and store instructions 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 the above. any suitable combination. More specific examples (non-exhaustive list) of readable storage media 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), Compact Disk Read Only Memory (CD-ROM), Digital Versatile Disk (DVD), Memory Stick, Floppy Disk, Mechanically encoded device, such as a punch hole with instructions stored on it The protruding structure in the card or groove, and any suitable combination of the above. The computer programs described herein may be downloaded from a readable storage medium to various computing/processing devices, or to an external computer or external storage device over a network, such as the Internet, a local area network, a wide area network, and/or a wireless network. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and/or edge servers. A 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 on a readable storage medium in the respective computing/processing device. A computer program used to perform the operations of this application may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or any other programming language in one or more programming languages. A combination of source code or object code written in programming languages including object-oriented programming languages—such as Smalltalk, C++, etc., and conventional procedural programming languages—such as the “C” language or similar programming languages. The computer program may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server . In situations involving remote computers, the remote computer can be connected to the user's computer through any kind of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (such as an Internet service provider through the Internet). connect). In some embodiments, electronic circuits are personalized by utilizing state information from a computer program, For example, a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), the electronic circuit can execute computer readable program instructions, thereby implementing various aspects of the present application.

Various aspects of the present application are described herein with reference to flowchart illustrations and/or block diagrams of methods, systems and computer program products according to embodiments of the present application. It will 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 may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, thereby producing a machine such that the programs, when executed by the processor of the computer or other programmable data processing apparatus, produce A device that implements the functions/actions specified in one or more blocks in the flowchart and/or block diagram. These computer programs can also be stored in readable storage media. These computer programs cause computers, programmable data processing devices and/or other devices to work in specific ways. Therefore, the readable storage medium storing the computer program includes a An article of manufacture that includes instructions for implementing various aspects of the functions/acts specified in one or more blocks of the flowcharts and/or block diagrams.

A computer program may also be loaded onto a computer, other programmable data processing apparatus, or other equipment, such that a series of operational steps are performed on the computer, other programmable data processing apparatus, or other equipment to produce a computer-implemented process, such that A computer program executing on a computer, other programmable data processing apparatus, or other device implements the functions/acts specified in one or more blocks of the flowcharts and/or block diagrams.

In the description of this specification, reference to the terms "one embodiment," "some embodiments," "examples," or "specific examples" or the like means that a particular feature, structure, material, or characteristic is described in connection with the embodiment or example. Included in at least one embodiment or example of this application. In this specification, the schematic expressions of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments. Furthermore, those skilled in the art may join and combine the different embodiments or examples described in this specification.

The above are only preferred embodiments of the present application and do not limit the present application in any way. Any person skilled in the technical field who makes any form of equivalent substitution or modification to the technical solutions and technical contents disclosed in this application without departing from the scope of the technical solutions of this application shall be deemed to have done so without departing from the technical solutions of this application. The content still falls within the protection scope of this application.

Claims

A quantum chip adjustable coupler testing and characterization method, which is characterized by including:

A first experiment is performed on the tunable coupler and the first qubit, and the first experiment is used to obtain the variation of the first amplitude of the first qubit with the DC voltage and the frequency of the control signal, wherein, The adjustable coupler is coupled to the first qubit, the first amplitude is the amplitude of the first signal carrying quantum state information in the reading cavity of the first qubit, and the DC voltage is the The DC operating voltage of the adjustable coupler, the control signal is a signal used to adjust the quantum state of the first qubit;

The DC spectrum of the adjustable coupler is obtained based on the change.
The method of claim 1, wherein performing a first experiment on the tunable coupler and the first qubit includes:

Configuring the traversal range of the DC voltage as a first range;

Configuring the traversal range of the frequency of the control signal to be a second range;

Traverse the DC voltage within the first range, and traverse the frequency of the control signal applied to the first qubit within the second range each time the DC voltage is traversed;

Obtain the change of the first amplitude of the first qubit with the DC voltage and the frequency of the control signal.
The method of claim 2, wherein the DC voltage is traversed in the first range according to a first step, wherein the first step is preconfigured.
The method of claim 2, wherein the frequency of the control signal is traversed in the second range according to a second step size, wherein the second step size is preconfigured.
The method of claim 1, wherein said obtaining the DC spectrum of the adjustable coupler based on the change includes:

Obtain coordinate information of several points located at the energy level split based on the change, where the coordinate information includes the value of the DC voltage and the corresponding value of the frequency of the control signal;

The DC spectrum of the adjustable coupler is obtained based on the coordinate information.
The method of claim 5, wherein said obtaining the DC spectrum of the adjustable coupler based on the coordinate information includes:

Perform fitting processing on the data contained in the coordinate information to obtain the DC spectrum of the adjustable coupler.
The method according to claim 6, characterized in that the data contained in the coordinate information is fitted according to the following fitting function:

Where, x is the DC voltage, y is the frequency of the control signal, and A, B, d, m, and δ are parameters of the fitting function.
A quantum chip adjustable coupler testing and characterization device, which is characterized by including:

A first experiment execution unit configured to perform a first experiment on the tunable coupler and the first qubit, the first experiment being used to obtain the first amplitude of the first qubit as a function of the DC voltage and the control signal changes in frequency, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the first signal carrying quantum state information in the reading cavity of the first qubit. The amplitude of the DC voltage is the DC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

A spectrum acquisition unit configured to acquire the DC spectrum of the adjustable coupler based on the changing conditions.
A quantum chip adjustable coupler testing and characterization method, which is characterized by including:

A first experiment is performed on the tunable coupler and the first qubit, and the first experiment is used to obtain the variation of the first amplitude of the first qubit with the AC voltage and the frequency of the control signal, wherein, The adjustable coupler is coupled to the first qubit, the first amplitude is the amplitude of the first signal carrying quantum state information in the reading cavity of the first qubit, and the AC voltage is the The AC operating voltage of the adjustable coupler, the control signal is a signal used to adjust the quantum state of the first qubit;

The AC spectrum of the adjustable coupler is obtained based on the change.
A quantum chip adjustable coupler testing and characterization device, which is characterized by including:

A first experiment execution unit configured to perform a first experiment on the tunable coupler and the first qubit, the first experiment being used to obtain the first amplitude of the first qubit as a function of the AC voltage and the control signal changes in frequency, wherein the adjustable coupler is coupled to the first qubit, and the first amplitude is the first signal carrying quantum state information in the reading cavity of the first qubit. The amplitude of the AC voltage is the AC operating voltage of the adjustable coupler, and the control signal is a signal used to adjust the quantum state of the first qubit;

A spectrum acquisition unit configured to acquire the AC spectrum of the adjustable coupler based on the changing conditions.
A quantum control system, characterized by utilizing the quantum chip adjustable coupler test and characterization method described in any one of claims 1 to 7, or utilizing the quantum chip adjustable coupler test and characterization method described in claim 9 , or include the quantum chip adjustable coupler test and characterization device according to claim 8, or include the quantum chip adjustable coupler test and characterization device according to claim 10.
A quantum computer, characterized by comprising the quantum control system according to claim 11.
A readable storage medium with a computer program stored thereon, characterized in that, when executed by a processor, the computer program can implement the quantum chip adjustable coupler test characterization described in any one of claims 1-7 method, or implement the quantum chip tunable coupler test and characterization method described in claim 9.