Method and apparatus for determining a superconducting impedance transformation parametric amplifier, a superconducting impedance transformation parametric amplifier, electronic equipment, and computer program

Abstract

The present application provides a method and apparatus for determining a superconducting impedance transformation parametric amplifier, a superconducting impedance transformation parametric amplifier, an electronic device, a computer program product, and a computer-readable storage medium, and the method for determining a superconducting impedance transformation parametric amplifier includes the steps of: calculating an impedance value of an impedance transformation line of a superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier based on a wavelength parameter, a gain parameter, and a bandwidth parameter; calculating a linewidth size of a coplanar waveguide of the superconducting impedance transformation parametric amplifier based on the impedance value of the impedance transformation line; calculating a stub size of the superconducting impedance transformation parametric amplifier based on the impedance value of the impedance transformation line and the capacitance value of the amplifier; and determining a structural parameter of the superconducting impedance transformation parametric amplifier based on the linewidth size and the stub size.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application is filed based on and claims priority from a Chinese patent application having application number 202210815436.0 and filing date July 8, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to signal processing technology, and in particular to a method and apparatus for determining a superconducting impedance transparametric amplifier, a superconducting impedance transparametric amplifier, an electronic device, a computer program product, and a computer-readable storage medium. [Background technology]

[0003] A quantum bit (qubit) on a superconducting chip is a quantum state carrier that conveys quantum information. Superconducting quantum computing has the advantage of fast operating speed and is widely applied. During use, the superconducting quantum chip is in an extremely low-temperature (<30 mK) environment, which is significantly affected by noise. Therefore, the signal output from the superconducting quantum chip is very weak. Therefore, a multi-stage amplifier must generally be added after the output terminal to increase the signal strength. Related Technology: Commercial cryogenic amplifiers generally operate at a temperature of 4 K, resulting in significant thermal noise. However, Josephson parametric amplifiers, which operate at the same temperature as the superconducting quantum chip, have excellent characteristics, such as maximum gain and no additional noise. Therefore, Josephson parametric amplifiers are essential devices for superconducting quantum computing. At the same time, an impedance converter can be used to achieve a more gradual transition between the environment impedance and the amplifier impedance using an additional circuit, enabling a wider spectral range of coupling between the environment and the parametric oscillator circuit. However, due to the complex structure of the Josephson parametric amplifier and the impedance converter, the combined impedance-converting Josephson parametric amplifier has a low yield during the processing, which increases the manufacturing cost of the quantum chip. At the same time, the impedance-converting Josephson parametric amplifier is sensitive to parameters, requires a large capacitance, and has a large insertion loss of the dielectric capacitance, which results in insufficient performance improvement of the impedance-converting Josephson parametric amplifier and excessively high power consumption. Summary of the Invention

[0004] The embodiments of the present application provide a method and apparatus for determining a superconducting impedance transparametric amplifier, a superconducting impedance transparametric amplifier, an electronic device, a computer program product, and a computer-readable storage medium, which can effectively improve the performance of the superconducting impedance transparametric amplifier, reduce the loss of the superconducting impedance transparametric amplifier, and at the same time, improve the manufacturing yield of the superconducting impedance transparametric amplifier.

[0005] The technical solution of the embodiments of the present application is realized as follows:

[0006] An embodiment of the present application provides a method for determining a superconducting impedance transparametric amplifier, which is performed by an electronic device, and the method for determining a superconducting impedance transparametric amplifier includes: determining a center wavelength parameter, a gain parameter, and a bandwidth parameter of the superconducting transimpedance parametric amplifier based on the usage environment parameters of the quantum chip; calculating an impedance value of an impedance transformation line of the superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier based on the center wavelength parameter, the gain parameter, and the bandwidth parameter; calculating a line width size of the coplanar waveguide of the superconducting impedance transformation parametric amplifier based on the impedance value of the impedance transformation line; calculating a stub size of the superconducting transimpedance parametric amplifier based on the impedance value of the impedance transformation line and the capacitance value of the amplifier; and determining structural parameters of the superconducting transimpedance parametric amplifier based on the line width size and the stub size.

[0007] An embodiment of the present application further provides a determination device for a superconducting impedance transparametric amplifier, the determination device for a superconducting impedance transparametric amplifier comprising: a signal transmission module configured to determine a center wavelength parameter, a gain parameter, and a bandwidth parameter of the superconducting transimpedance parametric amplifier based on the usage environment parameters of the quantum chip; a simulation design module configured to calculate an impedance value of an impedance transformation line of the superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier based on the center wavelength parameter, the gain parameter, and the bandwidth parameter; The simulation design module is configured to calculate a line width size of a coplanar waveguide of the superconducting impedance transformation parametric amplifier based on an impedance value of the impedance transformation line; the simulation design module is configured to calculate a stub size of the superconducting impedance transformation parametric amplifier based on an impedance value of the impedance transformation line and a capacitance value of the amplifier; The simulation design module is configured to determine structural parameters of the superconducting transimpedance parametric amplifier based on the linewidth size and the stub size.

[0008] An embodiment of the present application further provides a superconducting transimpedance parametric amplifier, the superconducting transimpedance parametric amplifier comprising: an impedance converter and a Josephson parametric amplifier, the impedance converter and the Josephson parametric amplifier being integrated on the same quantum chip; the impedance transformer includes a coplanar waveguide, the length of the coplanar waveguide being 1 / 2 wavelength of a center frequency; The Josephson parametric amplifier includes a stub, the length of the stub matching the capacitance value of the superconducting transimpedance parametric amplifier.

[0009] An embodiment of the present application provides an electronic device, the electronic device comprising: a memory for storing computer-executable instructions; and a processor that, when executing computer-executable instructions stored in the memory, implements the superconducting impedance transparametric amplifier determination method provided by the embodiments of the present application.

[0010] An embodiment of the present application provides a computer program product, which includes computer-executable instructions that, when executed by a processor, implement a determination method for a superconducting impedance transforming parametric amplifier provided by an embodiment of the present application.

[0011] An embodiment of the present application further provides a computer-readable storage medium, which stores computer-executable instructions, which, when executed by a processor, realize the determination method for a superconducting impedance transforming parametric amplifier provided by the embodiment of the present application.

[0012] The embodiments of the present application have the following beneficial effects:

[0013] In the present application, the center wavelength parameters, gain parameters, and bandwidth parameters of the superconducting impedance transparametric amplifier are determined based on the usage environment parameters of the quantum chip; the impedance value of the impedance transformation line of the superconducting impedance transparametric amplifier and the capacitance value of the amplifier are calculated based on the wavelength parameters, gain parameters, and bandwidth parameters; the linewidth size of the coplanar waveguide of the superconducting impedance transparametric amplifier is calculated based on the impedance value of the impedance transformation line; the stub size of the superconducting impedance transparametric amplifier is calculated based on the impedance value of the impedance transformation line and the capacitance value of the amplifier; and the structure of the superconducting impedance transparametric amplifier is determined based on the linewidth size and stub size. In this way, the method for determining the superconducting impedance transparametric amplifier provided by the present application can not only better improve the performance of the superconducting impedance transparametric amplifier and reduce the loss of the superconducting impedance transparametric amplifier, but also utilize the structure of the superconducting impedance transparametric amplifier to improve the yield and reduce the manufacturing cost in the production of superconducting impedance transparametric amplifiers, which is favorable for the large-scale popularization of superconducting quantum chips. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram of a usage scene of a method for determining a superconducting impedance transparametric amplifier according to an embodiment of the present application; [Figure 2] 1 is a schematic diagram of the structure of a determination device for a superconducting impedance transparametric amplifier according to an embodiment of the present application; [Figure 3] 1 is a schematic diagram of an alternative configuration of a parametric amplifier in an embodiment of the present application; [Figure 4] 1 is a schematic diagram of an alternative configuration of a parametric amplifier in an embodiment of the present application; [Figure 5A]1 is a schematic diagram of an optional process of a determination method for a superconducting impedance transparametric amplifier in an embodiment of the present application. [Figure 5B] 1 is a schematic diagram of an optional process of a determination method for a superconducting impedance transparametric amplifier in an embodiment of the present application. [Figure 6] 1 is a schematic diagram of the structure of a superconducting transimpedance parametric amplifier in an embodiment of the present application; [Figure 7A] FIG. 1 is a schematic diagram of a capacitance used in a quantum parametric amplifier in the related art. [Figure 7B] FIG. 2 is a schematic diagram illustrating the principle of stub capacitance in an embodiment of the present application. [Figure 7C] FIG. 2 is a cross-sectional schematic diagram of a stub capacitance in an embodiment of the present application. [Figure 8] FIG. 1 is a schematic diagram illustrating the use of a superconducting transimpedance parametric amplifier in an embodiment of the present application. [Figure 9] 1 is a schematic diagram of the test effect of a superconducting impedance transparametric amplifier in an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0015] In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be described in more detail below with reference to the drawings, and the described embodiments should not be considered as limitations on the present application. All other embodiments that can be obtained by those skilled in the art without any creative efforts fall within the scope of protection of the present application.

[0016] With respect to "some embodiments" described below, a subset of all possible embodiments is described, but it is understood that "some embodiments" may be the same or different subsets of all possible embodiments, and may be combined with each other if not inconsistent.

[0017] Before describing the embodiments of the present application in more detail, the nouns and terms used in the embodiments of the present application will be explained. The nouns and terms used in the embodiments of the present application are interpreted as follows.

[0018] 1) Layout: Also known as a circuit layout, this is a blueprint that describes how components in a circuit are located, arranged, and connected; it is a two-dimensional geometric description of the physical situation of the actual circuit.

[0019] 2) Superconducting qubit: A superconducting qubit is a superconducting quantum circuit formed using a Josephson junction.

[0020] 3) Superconducting Quantum Chip: A superconducting quantum chip is the central processor of a superconducting quantum computer. A quantum computer is a machine that performs calculations using the principles of quantum mechanics. Based on the principles of superposition and quantum entanglement in quantum mechanics, quantum computers have relatively strong parallel processing capabilities and can solve problems that are difficult to calculate with some classical computers. Due to the zero-resistance characteristics of superconducting qubits and a manufacturing process that is close to that of integrated circuits, quantum computing systems built using superconducting qubits are one of the most promising systems in related technologies for realizing practical quantum computing.

[0021] 4) Coplanar Waveguide (CPW): A microwave planar transmission line with excellent performance and easy processing, used to transmit microwave signals. A central conductor strip is created on one side of a dielectric substrate, and conductor planes are created on both sides close to the central conductor strip, thus forming a coplanar waveguide (also known as a coplanar microwave transmission line). Coplanar waveguides propagate TEM waves and have no cutoff frequency. Because the central conductor and conductor planes are located in the same plane, it is very convenient to mount components in parallel on the coplanar waveguide, which can be used to create monolithic microwave integrated circuits with the transmission line and elements on the same side. Coplanar waveguide technology is widely used in superconducting quantum chips.

[0022] 5) Etching / Wet Etching: This is photolithography etching, an important step in semiconductor processing, and a patterning technique that selectively corrodes (etches) and peels off the surface of a semiconductor substrate according to a layout design. Etching is a process that uses chemical or physical methods to selectively remove unwanted material from the surface of a silicon sheet, and its basic goal is to accurately replicate the mask pattern on the coated silicon sheet. Wet etching is an etching method in which the etching material is immersed in a corrosive liquid to corrode it, and has the advantages of good selectivity and reproducibility, high production efficiency, simple equipment, and low cost.

[0023] 6) Micro-nano processing: Micro-nano manufacturing technology refers to the design, processing, assembly, integration and application technology of parts or systems composed of specific elements, where the specific elements are elements with sizes at the sub-millimeter, micron or nanometer level.

[0024] 7) Component: A general term for elements and devices, such as resistors, capacitances, and inductances, which are electronic parts and components in a circuit.

[0025] 8) Amplifier: A microwave power amplification device.

[0026] 9) Josephson Parametric Amplifier (JPA): Usually consists of one capacitance and a pair of Josephson junctions connected in parallel. The amplification process of a Josephson parametric amplifier uses a nonlinear parametric process to amplify the input microwave signal. The nonlinear parametric process is the nonlinear parametric process of the Josephson junction under external magnetic flux modulation.

[0027] 10) Input Signal: The input signal is the microwave signal to be amplified that is input to the amplifier.

[0028] 11) Pump Signal: The pump signal is a microwave that is provided to the amplifier through the pump port to effect energy conversion and amplification of the input signal.

[0029] 12) Idler Signal: The idler signal is a non-demand microwave power that is automatically generated by a hybrid non-linear process.

[0030] 13) Impedance Matching: Impedance matching is used to solve the matching between microwave transmission lines and microwave devices. By using an additional circuit to perform impedance matching, a more gradual transition can be achieved between the environment impedance and the amplifier impedance, and a wider spectral range of coupling can be achieved between the environment and the parametric oscillator circuit.

[0031] 14) Impedance Matched Josephson Parametric Amplifier (IMPA): An impedance matched Josephson parametric amplifier is obtained by integrating an impedance matched module into a Josephson parametric amplifier, which can realize parametric amplification over a wider bandwidth range.

[0032] 15) Stub Capacitance: A stub is a transmission line or waveguide for connection. A stub is used as a capacitance in the range below the target frequency and is called stub capacitance. A stub uses a waveguide structure whose length is less than 1 / 4 wavelength of the target frequency and is connected to an open-circuit load.

[0033] 16) Dielectric Capacitance: By using an insulating dielectric material such as SiOx or AlOx between the lower and uppermost metal layers of the chip, the lower and uppermost metal layers of the chip are separated by tens to hundreds of nanometers to form a lumped capacitance, and the formed capacitance is a dielectric capacitance.

[0034] 18) Photolithography: Also known as optical planographic lithography or ultraviolet lithography, this is a precision machining process for patterning components and is a key step in semiconductor manufacturing.

[0035] The following describes a method for processing a frequency control signal for a quantum bit according to an embodiment of the present application. FIG. 1 is a schematic diagram of a usage scenario of the method for processing a frequency control signal for a quantum bit according to an embodiment of the present application. Referring to FIG. 1, a superconducting quantum computer is an electronic device that performs general-purpose calculations using quantum logic. Superconducting quantum computers have attracted widespread attention because they can significantly improve computational efficiency when solving certain specific problems compared to conventional computers. Superconducting quantum chips can achieve large-scale integration using related semiconductor process technologies. At the same time, superconducting quantum bits exhibit superior performance to other physical systems in key aspects of quantum computing, such as interaction control, selective manipulation, and error correction, making them one of the most promising platforms for realizing a superconducting quantum computer. Specifically, a superconducting quantum computer mainly includes a superconducting quantum chip and a hardware system for chip control and measurement. The hardware system mainly includes various microwave frequency band signal generators and various microwave frequency band devices, including but not limited to filters, amplifiers, and isolators, as well as a dilution refrigerator equipped with a microwave transmission line. The key technology for superconducting quantum computers is precise control and accurate measurement of the qubit states on superconducting quantum chips. The intrinsic energy of superconducting qubits is in the gigahertz (GHz) microwave band. To operate quantum gates and read their quantum states, pulsed microwave signals with specific phases, amplitudes, and durations must be applied to the superconducting qubits. Therefore, superconducting quantum computers require a large number of GHz microwave frequency band signal sources and GHz sampling rate arbitrary waveform signal modulation. Furthermore, to maintain the coherent state of superconducting qubits for long periods of time, the superconducting qubits must be maintained at millikelvin temperatures to reduce thermal noise. A dilution refrigerator is typically used to provide a low-temperature environment for the superconducting quantum chip. The dilution refrigerator must include a microwave transmission line to transmit microwave signals generated at room temperature to the cryogenic superconducting qubits.As shown in Figure 1, the control subsystem controls the qubit state to perform quantum computations such as single-bit logic gate calculations and two-bit logic gate calculations. The superconducting quantum chip is used to transport the quantum computation information. The measurement subsystem reads the qubit's final state and obtains the quantum computation result. The superconducting quantum chip is placed in a cryogenic environment. The control subsystem generates a pulse-modulated signal according to the quantum computation operation demands, inputs a series of microwave pulse sequences into the superconducting quantum chip, and performs operations on the qubit's quantum state. After all operations are completed, the measurement system outputs a measurement pulse signal to the superconducting quantum chip. The change in the returned signal obtains the qubit's state information and ultimately the computation result. During the measurement process, commercial cryogenic amplifiers generally operate at a temperature of 4K, resulting in significant thermal noise. However, Josephson parametric amplifiers, which operate at the same temperature as the superconducting quantum chip, have excellent characteristics such as significant gain and no additional noise. Therefore, Josephson parametric amplifiers are essential for superconducting quantum computing. At the same time, the impedance converter allows for a more gradual transition between the environment impedance and the amplifier impedance using an additional circuit, achieving a wider spectral range of coupling between the environment and the parametric oscillator circuit. However, due to the complex structure of the Josephson parametric amplifier and the impedance converter, the combined impedance-transforming Josephson parametric amplifier suffers from low processing yields, increasing the manufacturing costs of quantum chips. It is also sensitive to parameters, requires a large capacitance, and has a large dielectric capacitance insertion loss, resulting in insufficient performance improvement and excessive power consumption. Therefore, a new superconducting impedance-transforming parametric amplifier structure is needed to ensure the high yield rate of superconducting impedance-transforming parametric amplifiers with large bandwidth and low insertion loss, approaching the quantum limit noise, and to meet the large-scale use of quantum chips.

[0036] The structure of the superconducting impedance transparametric amplifier determining device of the embodiment of the present application will be described in detail below, but the superconducting impedance transparametric amplifier determining device can be implemented in various forms, such as a superconducting quantum chip with a superconducting impedance transparametric amplifier determining device processing function, such as the superconducting quantum chip 200 in Figure 1, or an integrated chip with a superconducting impedance transparametric amplifier determining device processing function. Figure 2 is a schematic diagram of the structure of the superconducting impedance transparametric amplifier determining device according to the embodiment of the present application, and it can be understood that Figure 2 only shows an exemplary structure of the superconducting impedance transparametric amplifier determining device, and does not show the entire structure, and some or all of the structure shown in Figure 2 can be implemented as needed.

[0037] The apparatus for determining a superconducting impedance transformation parametric amplifier provided by the embodiment of the present application includes at least one processor 201, a memory 202, a user interface 203, and at least one network interface 204. The components in the apparatus for determining a superconducting impedance transformation parametric amplifier are coupled via a bus system 205. It can be understood that the bus system 205 is used to realize connection and communication between these components. The bus system 205 includes a power bus, a control bus, and a status signal bus in addition to a data bus. However, for the sake of clarity, various buses are referred to as the bus system 205 in FIG. 2.

[0038] Here, the user interface 203 may include a display, a keyboard, a mouse, a trackball, a click wheel, keys, buttons, a touchpad or a touch screen, or the like.

[0039] It can be understood that memory 202 may be volatile or nonvolatile memory, or may include both volatile and nonvolatile memory. In the embodiment of the present application, memory 202 can store data to support operations on the superconducting quantum chip in the terminal. Examples of this data include any computer programs, such as an operating system and application programs, for running on the superconducting quantum chip of the terminal. Here, the operating system includes various system programs, such as a framework layer, a core library layer, and a driver layer, and is used to realize various basic services and process hardware-based tasks. The application programs can include various application programs.

[0040] In some embodiments, the superconducting impedance transformation parametric amplifier determining apparatus provided by the embodiments of the present application may be realized by adopting a combination of software and hardware, for example, the superconducting impedance transformation parametric amplifier determining apparatus provided by the embodiments of the present application may be a processor in the form of a hardware decoder processor programmed to execute the superconducting impedance transformation parametric amplifier determining method provided by the embodiments of the present application. For example, the processor in the form of a hardware decoder processor may adopt one or more application specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), or other electronic elements.

[0041] As an example of the superconducting impedance transformation parametric amplifier determination device provided by the embodiments of the present application being implemented by adopting a combination of software and hardware, the superconducting impedance transformation parametric amplifier determination device provided by the embodiments of the present application may be directly embodied as a combination of software modules executed by the processor 201, the software modules may be located in a storage medium, the storage medium is located in the memory 202, the processor 201 reads the executable instructions included in the software modules in the memory 202, and combines the necessary hardware (e.g., including the processor 201 and other components connected to the bus 205) to complete the superconducting impedance transformation parametric amplifier determination method provided by the embodiments of the present application.

[0042] By way of example, processor 201 may be a superconducting electronic chip with signal processing capabilities, such as a general-purpose processor, a digital signal processor (DSP), or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, etc. Here, a general-purpose processor may be a microprocessor or any conventional processor, etc.

[0043] As an example of the superconducting impedance transformation parametric amplifier determination apparatus provided by the embodiments of the present application being implemented using hardware, the apparatus provided by the embodiments of the present application can be directly implemented using a processor 201 in the form of a hardware decoder processor, for example, implemented by one or more application specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs) or other electronic elements to realize the superconducting impedance transformation parametric amplifier determination method provided by the embodiments of the present application.

[0044] The memory 202 in the embodiment of the present application is used to store various types of data to support the operation of the superconducting impedance transparametric amplifier determiner. Examples of these data include any executable instructions for operating on the superconducting impedance transparametric amplifier determiner, such as executable instructions, and a program implementing the superconducting impedance transparametric amplifier determination method of the embodiment of the present application may be included in the executable instructions.

[0045] In some embodiments, the superconducting impedance transparametric amplifier determination device provided by the embodiments of the present application may be realized in a software manner. FIG. 2 shows the superconducting impedance transparametric amplifier determination device stored in memory 202, which may be a program and plug-in type software and includes a series of modules. An example of a program stored in memory 202 may include the superconducting impedance transparametric amplifier determination device. The superconducting impedance transparametric amplifier determination device includes a signal transmission module 2081 and a simulation design module 2082. The signal transmission module 2081 and the simulation design module 2082 may form simulation design software for a microwave generation method to calculate structural parameters of the superconducting impedance transparametric amplifier. When the software modules in the superconducting impedance transparametric amplifier determination device are read into random access memory (RAM) and executed by the processor 201, the method for determining a superconducting impedance transparametric amplifier provided by the embodiments of the present application is realized. The functions of each software module in the superconducting impedance transparametric amplifier determination device are as follows: a signal transmission module 2081 configured to determine a center wavelength parameter, a gain parameter, and a bandwidth parameter of the superconducting transimpedance parametric amplifier based on the usage environment parameters of the quantum chip; and a simulation design module 2082 configured to determine an impedance value of an impedance transformation line of the superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier using the wavelength parameter, the gain parameter, and the bandwidth parameter as constraints.

[0046] The simulation design module 2082 is further configured to calculate a line width size of the coplanar waveguide of the superconducting impedance transformation parametric amplifier based on the impedance value of the impedance transformation line.

[0047] The simulation design module 2082 is further configured to calculate a stub size of the superconducting transimpedance parametric amplifier based on an impedance value of the impedance transformation line and a capacitance value of the amplifier.

[0048] The simulation design module 2082 is further configured to determine structural parameters of the superconducting transimpedance parametric amplifier based on the linewidth size and the stub size.

[0049] The present application further provides a computer program product, the computer program product including computer-executable instructions, the computer-executable instructions being stored in a computer-readable storage medium, a processor of an electronic device reading the computer instructions from the computer-readable storage medium, the processor executing the computer instructions, and causing the electronic device to perform different embodiments and combinations of embodiments provided in various selectable implementation forms of the above-mentioned method for determining a superconducting impedance transparametric amplifier.

[0050] Before introducing the method for determining the superconducting impedance transformation parametric amplifier proposed in this application, we will first introduce the superconducting impedance transformation parametric amplifier of the related art. Specifically, referring to Figure 3, Figure 3 is a schematic diagram of an optional structure of the parametric amplifier in the embodiment of this application. In the related art, a superconducting Josephson junction loop is used as a nonlinear element to form a superconducting parametric resonator circuit through a parallel connection with a dielectric capacitance. To increase the bandwidth, the related art uses impedance transformation technology, specifically an impedance matching structure consisting of a waveguide when the center frequency is at the center of the amplification bandwidth, where the waveguide has a structure in which one 1 / 4 wavelength waveguide and one 1 / 2 wavelength waveguide are connected in series. Amplification is achieved by applying a drive and DC bias at approximately twice the amplification center frequency through a coplanar waveguide near the Josephson junction loop. As shown in Figure 3, a parametric amplifier is typically driven by a resonant circuit (typically a resonant circuit with inductance-capacitance connected in parallel), a tunable nonlinear element (semiconductors typically use variable capacitance, while superconducting circuits typically use adjustable inductance created by a Josephson junction), and an externally applied pump that doubles the resonant frequency.

[0051] Referring to Figure 4, Figure 4 is a schematic diagram of a selectable structure of a parametric amplifier in an embodiment of the present application. As a typical superconducting nonlinear device, a superconducting Josephson junction plays a central role in a superconducting parametric amplifier. Due to the flux quantization effect in the Josephson junction loop, the loop behaves like an inductor that can be modulated by an externally applied magnetic flux under low-current conditions. Low-current is an industry abbreviation for a low-current grounding line selector. It is suitable for single-phase grounding line selection in systems with an ungrounded neutral point (3 kV to 66 kV) or a grounded neutral point via a resistor or arc-suppressing coil. Furthermore, due to the properties of superconductivity, its resistance loss can be ignored in ideal cases. When a flux pump approximately twice the input signal is applied to the superconducting loop, the input signal can be effectively amplified. A superconducting parametric amplifier is essentially a nonlinear resonator, and it is the superconducting phase that oscillates here. Superconductivity is a typical macroquantum phenomenon, in which a large number of conduction electrons couple and condense into Cooper pairs through a certain mechanism, forming a collective-mode quantum state. Superconducting condensation opens an energy gap in the energy band. The energy gap corresponds to an energy scale, and the energy scale corresponds to interactions. Superconducting condensation can eliminate all interactions below this energy gap, providing excellent protection for the system and achieving the desired effects for many applications: zero resistance and perfect diamagnetism. Superconductivity is a macroscopic quantum effect, and despite the macroscopic number of participating particles, only the phase is expressed. Circuit noise typically originates from uncontrollable degrees of freedom. In superconducting parametric amplifiers, only this single participating degree of freedom is present; the other related degrees of freedom are frozen by the protection of the superconducting energy gap, resulting in extremely low spontaneous noise. This is commonly referred to as quantum-limited noise in superconducting parametric amplifiers. Nonlinearity correlates the amplifier's oscillation frequency with the amplitude; for JPAs, the larger the amplitude, the lower the resonant frequency. As the amplitude approaches a critical value, even very weak perturbations can cause significant changes in the system's response characteristics.JPA requires first driving the system close to this critical state using a relatively high-power pump signal. Then, when an input signal is introduced, it corresponds to this perturbation, changing the response characteristics and resulting in a change in output power. During this process, there is a fixed phase relationship between the perturbation (signal) and the pump. When the signal and pump frequencies match, significant amplification occurs only when they are in phase. However, when they are out of phase by 90 degrees, the output power is reduced. This theoretically satisfies the aforementioned condition for "exceeding the quantum limit." Exceeding the quantum limit requires a strict condition: it can only occur when the signal frequency matches the pump frequency. If there is a deviation between the two, the signal light can always be decomposed into two components, one half in phase with the pump light and the other half 90 degrees out of phase with the pump light, based on the trigonometric relationship. Therefore, the overall gain is independent of the initial phase; that is, the minimum additive noise is half a photon.

[0052] However, this amplifier also suffers from a problem of too narrow a bandwidth frequency. This is particularly true when multiplexed readout for superconducting quantum computing places a bandwidth requirement on the bandwidth of superconducting parametric amplifiers. To solve this technical problem, related technologies use impedance converters. The impedance converter reduces the impedance difference between the superconducting parametric amplifier and the 50 ohm (Ω) environment, making the coupling between them smoother. By reducing the impedance difference between the environment and the amplified resonant circuit, a narrow bandwidth of approximately 10 megahertz (MHz) can be amplified and extended to the required range of several hundred megahertz. However, this process requires controlling the strength of the impedance conversion. A bandwidth that is too large can result in a reduction in overall gain. Ultimately, the goal is achieved by trading greater bandwidth for some gain.

[0053] All of the solutions for superconducting impedance transformation parametric amplifiers provided by the related art use a structure in which one quarter-wavelength waveguide and one half-wavelength waveguide are connected in series. Here, the quarter-wavelength waveguide plays the role of impedance transformation. The half-wavelength waveguide introduces an auxiliary resonant mode, which can equivalently increase the bandwidth by introducing a second resonant point. However, the applicant has discovered that the quarter-wavelength waveguide in the related art cannot effectively improve the overall performance of the amplifier and may even increase the sensitivity of the entire circuit of the superconducting impedance transformation parametric amplifier to fluctuations in processing parameters. At the same time, because the impedance transformer and parametric amplifier used in the superconducting impedance transformation parametric amplifier do not have the same planar structure, defects with low yield rates exist during the manufacturing process of the impedance transformation parametric amplifier, which increases the manufacturing cost of the impedance transformation parametric amplifier.

[0054] In order to overcome the above-mentioned deficiencies, an embodiment of the present application provides a superconducting impedance transformation parametric amplifier that can improve performance. Referring to FIG. 5A, FIG. 5A is a schematic diagram of an optional process of a determination method for a superconducting impedance transformation parametric amplifier in an embodiment of the present application, which can be performed by the above-mentioned electronic device, specifically including the following steps 501 to 505:

[0055] In step 501, the center wavelength parameter, the gain parameter and the bandwidth parameter of the superconducting transimpedance parametric amplifier are determined based on the usage environment parameters of the quantum chip.

[0056] For example, the usage environment parameters of the superconducting quantum chip include a maximum read frequency, a minimum read frequency, and a read frequency bandwidth range, where the read frequency bandwidth range is obtained by reading the cavity bandwidth range from the superconducting quantum chip, where the maximum read frequency is the maximum value among the multiple frequencies obtained after reading the cavity frequency multiple times with the superconducting quantum chip, and the minimum read frequency is the minimum value among the multiple frequencies obtained after reading the cavity frequency multiple times with the superconducting quantum chip. The central wavelength parameter and the bandwidth parameter satisfy the following matching conditions with the usage environment parameters: the bandwidth parameter is less than or equal to the read frequency bandwidth range, the central wavelength parameter is the ratio of the speed of light to the central frequency parameter, the result of adding the center frequency parameter and 0.5 times the bandwidth parameter is greater than or equal to the maximum frequency, and the result of subtracting the center frequency parameter and 0.5 times the bandwidth parameter is less than or equal to the minimum frequency.

[0057] The operating environment parameters of a superconducting quantum chip include a frequency bandwidth range. The frequency bandwidth range (bandwidth parameter) is determined by reading the bandwidth range of the cavity from the superconducting quantum chip. For example, the bandwidth range is 300 to 500 MHz, with 1 to 7 frequencies uniformly read. Any bandwidth within the above bandwidth range can be used as the bandwidth parameter for a superconducting impedance transparametric amplifier. Taking a 500 MHz bandwidth range as an example, determining the center frequency f of a superconducting impedance transparametric amplifier requires ensuring that the seven read frequencies are within the frequency range f-0.5w to f+0.5w, i.e., the value of the center frequency f is sufficient to satisfy the requirement that the seven read frequencies are within the range f-250 MHz to f+250 MHz. Furthermore, the center wavelength parameter can be determined based on the center frequency f. The center wavelength parameter is equal to the ratio of the speed of light to the center frequency.

[0058] For example, the usage environment parameters of the quantum chip further include the number of frequencies read simultaneously when reading the cavity frequency from the superconducting quantum chip, and the gain parameter and the usage environment parameter satisfy a matching condition that the gain parameter and the number of frequencies read simultaneously satisfy a negative correlation calculation relationship.

[0059] The required number of simultaneous reads is determined by the required saturation power. Specifically, if the power required to read one quantum bit is P, then N*P microwave power is required to simultaneously read N bits, where microwave power is the saturation power. Because parametric amplifiers exhibit output saturation, the higher the microwave power, the smaller the resulting gain; that is, the gain parameter is negatively correlated with microwave power. Typically, the saturation power is -115 dBm. However, the more amplifier frequencies need to be simultaneously read, the higher the required saturation power. This can increase the critical current of the Josephson junction when the amplifier circuit resonates, and the capacitance of the resonant circuit must also be increased by the same amount, resulting in a decrease in the gain parameter.

[0060] In step 502, the impedance value of the impedance transformation line of the superconducting impedance transformation parametric amplifier and the capacitance value of the amplifier are determined using the wavelength parameter, the gain parameter, and the bandwidth parameter as constraints.

[0061] For example, the impedance of an impedance transformation line is equal to the square root of the product of the characteristic impedance of a Josephson parametric amplifier and the environmental impedance, where the environmental impedance is 50 ohms. The characteristic impedance of a Josephson parametric amplifier is the square root of the ratio of the inductance to the capacitance of the Josephson parametric amplifier.

[0062] For example, the amplifier in "amplifier capacitance value" is actually a Josephson parametric amplifier, where the Josephson parametric amplifier is a superconducting impedance transparametric amplifier configuration, the capacitance value of the Josephson parametric amplifier is the capacitance value of the superconducting impedance transparametric amplifier, and the capacitance value of the Josephson parametric amplifier is the reciprocal of the product of the square of the center frequency and the inductance of the Josephson parametric amplifier.

[0063] After the impedance value of the impedance transformation line and the capacitance value of the amplifier are calculated based on the above example, it is necessary to use microwave simulation software to test whether the wavelength parameter, gain parameter, and bandwidth parameter calculated in step 501 can be realized, which corresponds to fine-tuning the impedance value of the impedance transformation line and the capacitance value of the amplifier using the wavelength parameter, gain parameter, and bandwidth parameter calculated in step 501 as condition constraints. In a specific embodiment, the impedance value of the impedance transformation line and the capacitance value of the amplifier are input into the simulation software to test whether the wavelength parameter, gain parameter, and bandwidth parameter calculated in step 501 can be output. If these parameter values can be output, fine-tuning is not necessary; if not, the impedance value of the impedance transformation line and the capacitance value of the amplifier are adjusted, and then input into the simulation software to test whether the wavelength parameter, gain parameter, and bandwidth parameter calculated in step 501 can be output. Adjustments are made until the wavelength parameter, gain parameter, and bandwidth parameter calculated in step 501 can be output.

[0064] In step 503, the line width size of the coplanar waveguide of the superconducting impedance transformation parametric amplifier is calculated based on the impedance value of the impedance transformation line.

[0065] For example, the line width includes the cross-sectional size and the length of the waveguide corresponding to the impedance transformation line. The line width is determined using microwave simulation software and is not calculated theoretically. First, the cross-sectional size corresponding to the impedance value of the impedance transformation line is determined through simulation. Specifically, a cross-sectional size is input into the simulation software, and the simulation software outputs an impedance value corresponding to the assumed cross-sectional size. The input cross-sectional size is then adjusted multiple times until the impedance value output by the simulation software is equal to the impedance value calculated in step 502. If the impedance value is equal, the input cross-sectional size is considered to be included in the line width. After determining the cross-sectional size, the cross-sectional size and the length of a selected waveguide are input into the simulation software, and the simulation software outputs the resonant frequency of the coplanar waveguide. Without changing the cross-sectional size, the waveguide length is adjusted multiple times until the resonant frequency output by the simulation software is equal to the center frequency parameter calculated in step 502.

[0066] By performing step 503, the coplanar waveguide linewidth is reduced to a distance of half the wavelength of the target center frequency. This reduction in the coplanar waveguide linewidth reduces the capacitance requirement for the amplifier. This can be reduced from 3 pF in the related art to 1 pF, making it possible to achieve low-loss capacitance using a planar structure. At the same time, the coplanar waveguide linewidth, which has a distance of half the wavelength, can achieve the same amplification performance as the related art. At the same time, the tolerance of the overall amplifier performance to offsets in processing parameters is improved, effectively improving the processing yield of the superconducting impedance transformation parametric amplifier and reducing production costs.

[0067] In some embodiments, if the characteristic impedance of the impedance transformation part required for the superconducting impedance transformation parametric amplifier needs to change, this can be achieved by adjusting the cross-sectional size of the coplanar waveguide. For example, if the impedance value of the impedance transformation line decreases, when the impedance value of the impedance transformation line decreases, the shape of the coplanar waveguide of the superconducting impedance transformation parametric amplifier can be adjusted to a curved state. Since the microwave resonance frequency of the waveguide does not obviously differ depending on whether it is a straight waveguide or a curved waveguide, the above technical effect can also be achieved. At the same time, the curved coplanar waveguide can adapt to different mounting demands of quantum chips in more usage scenarios.

[0068] In step 504, the stub size of the superconducting transimpedance parametric amplifier is calculated based on the impedance value of the impedance transformation line and the capacitance value of the amplifier.

[0069] For example, the number of stubs is preset, and the stubs are capacitances used to create the amplifier, and the capacitance value is calculated in step 502. For example, the number of stubs is 6. In the embodiment of the present application, if six stubs connected in parallel are used to realize the capacitance value calculated in step 502, the capacitance of each stub can be determined, that is, the capacitance value of step 502 is divided by the number of stubs to obtain the capacitance of each stub. Then, by setting the stub ports and simulation software and running a microwave simulation, the stub size required to realize the stub capacitance is obtained, and the stub size here includes the length of the stub and the width of the gap between the stub and the ground.

[0070] Referring to Figure 5B, this figure is a schematic diagram of a selectable process for a method for determining a superconducting impedance transformation parametric amplifier in an embodiment of the present application. In the process of performing steps 501 to 504, the simulation design software, consisting of the signal transmission module and the simulation design module in the aforementioned embodiment, determines the structural parameters of the superconducting impedance transformation parametric amplifier using a microwave network synthesis method, i.e., a method for finding the necessary circuit element parameters based on the required circuit representation. Similar to the concept of synthesizing a wide-bandwidth bandstop filter, to synthesize a gain with a certain bandwidth, it is sufficient to provide the amplifier circuit with the same center, bandwidth, and negative gain, i.e., the parameters obtained during attenuation, while simultaneously converting the positive resistor connected in parallel to the resonant circuit into a negative resistor with the same absolute value. The negative resistance-parallel inductance structure in the resulting new circuit is realized by a Josephson loop modulated by the parameters. In addition to the capacitance, inductance, and negative resistance required for the resonant amplifier circuit, this method also simultaneously provides the basic parameters of the impedance transformation part, i.e., the impedance value of the 1 / 2 impedance transformation line.

[0071] In step 505, the structural parameters of the superconducting transimpedance parametric amplifier are generated based on the linewidth size and the stub size.

[0072] For example, the linewidth size is the structural parameter of the superconducting impedance transformation parametric amplifier, and the stub size is the structural parameter of the superconducting impedance transformation parametric amplifier. Here, the coplanar waveguide and the stub are both important structures of the superconducting impedance transformation parametric amplifier. After the linewidth size and the stub size are known, a circuit is drawn using simulation software according to the linewidth size and the stub size, thereby obtaining the overall structure of the superconducting impedance transformation parametric amplifier. The obtained structure can be diverse, as long as it satisfies the linewidth size and the stub size.

[0073] After the structural parameters of the superconducting impedance transformation parametric amplifier are determined, the effect of the superconducting impedance transformation parametric amplifier can be further detected and adjusted based on the linewidth and stub sizes. Referring to FIG. 6, FIG. 6 is a schematic diagram of the structure of a superconducting impedance transformation parametric amplifier in an embodiment of the present application, where one end is an input / output microwave interface. Typically, the input / output of a circulator is separated from one port and then connected to a section of a coplanar waveguide with a center frequency of half a wavelength. This section of the waveguide is fabricated on the same base chip as the parametric amplifier using a coplanar waveguide structure. Finally, the coplanar waveguide is again connected in series with the superconducting parametric amplifier. A pump frequency approximately twice the center frequency of the amplification frequency can be applied near the Josephson junction of the parametric amplifier using a coplanar waveguide line to drive the operation of the entire amplifier. Therefore, in this application, the use of a stub structure in the Josephson parametric amplifier allows the amplifier's capacitance to be realized using a planar structure and loss to be reduced.

[0074] In some embodiments, to achieve the function of measuring the quantum bit state, the room temperature resistance value of the Josephson junction of the superconducting transimpedance parametric amplifier can be calculated based on the capacitance value of the amplifier and the center frequency of the superconducting transimpedance parametric amplifier, where the room temperature resistance value is used to measure the quantum bit state, and the center frequency of the superconducting transimpedance parametric amplifier can be determined based on different usage environment parameters of the superconducting transimpedance parametric amplifier to meet corresponding design and usage needs.

[0075] As an example, the inductance value of a parametric amplifier is equal to the square of the center frequency divided by the capacitance value of the parametric amplifier, and the room temperature resistance of the Josephson junction can be calculated based on equation (1).

[0076]

number

[0077] Referring to Figures 7A to 7C, Figure 7A is a schematic diagram of a capacitance used in a quantum parametric amplifier in related technology, Figure 7B is a schematic diagram of the principle of a stub capacitance in an embodiment of the present application, and Figure 7C is a schematic cross-sectional view of the stub capacitance in an embodiment of the present application.

[0078] When determining the structural parameters of a superconducting impedance transformation parametric amplifier, in addition to stable and reliable large-bandwidth amplification, attention should also be paid to the insertion loss of the amplifier itself, that is, the output when no amplification pump is provided, due to the loss introduced by the amplifier itself compared with the input. The insertion loss of related technologies mainly comes from the capacitance structure that constitutes the parametric amplifier.

[0079] 7A shows a capacitance used in a quantum parametric amplifier in the related art. This has the advantage of high capacitance density, making it possible to create the required capacitance in a small area, thereby reducing parasitic inductance due to the geometric structure. However, this type of capacitance has the disadvantage of high insertion loss because it uses a lossy dielectric material.

[0080] Referring to the stub capacitance shown in Figure 7B, the dielectric of the stub capacitance is a vacuum and a low-loss base material. This planar design avoids the use of amorphous dielectric materials, thereby reducing the insertion loss of the amplifier. Referring to Figure 7C, a short length of coplanar waveguide with one open-circuit load can be equivalent to a single capacitance to ground. Because a single stub provides little capacitance, increasing the length introduces too much parasitic inductance, affecting the amplifier gain. In practical designs, multiple similar stub capacitance structures connected in parallel with a Josephson junction loop form a parametric amplifier circuit. In practical applications, an air bridge may also be added at the base of the stub to reduce parasitic modes caused by long stub capacitances, as shown in Figure 7C.

[0081] Continuing with the structural schematic diagram of the superconducting impedance transparametric amplifier shown in Figure 6, the structural improvement of the superconducting impedance transparametric amplifier provided in this application will be described. Here, the impedance transformer and the Josephson parametric amplifier are integrated on the same quantum chip, and the impedance transformer includes a coplanar waveguide, the length of which is 1 / 2 wavelength of the center frequency of the Josephson parametric amplifier. The Josephson parametric amplifier includes a stub, the length of which matches the capacitance value of the superconducting impedance transparametric amplifier. Since the length of the stub is calculated based on the capacitance value of the superconducting impedance transparametric amplifier, the length of the stub matches the capacitance value of the superconducting impedance transparametric amplifier. The calculation method here can refer to the embodiment of step 504.

[0082] In some embodiments, when capacitance is realized by multiple parallel-connected open-circuit coplanar waveguide structures, a coplanar waveguide with a smaller gap and a coarser center can be used to reduce the parasitic series inductance. Specifically, the impedance value of a stub capacitance of a selected geometric size can be calculated over a certain range around a desired center frequency. Then, a lumped circuit with capacitance and inductance connected in series can be used to fit the impedance vs. frequency curve to obtain the capacitance and parasitic inductance values. Finally, the total capacitance value of the multiple parallel-connected stub capacitances can be guaranteed to meet the design value.

[0083] In some embodiments, when manufacturing a superconducting impedance transformation parametric amplifier, a section of a half-wavelength coplanar waveguide line can be connected in series between the parametric amplifier circuit and a pad for connecting to the environment, and the impedance transformation and Josephson parametric amplifier are integrated on the same chip, thereby reducing uncertainties introduced by artificial processing in previous discrete designs and improving the manufacturing yield of the superconducting impedance transformation parametric amplifier.

[0084] In some embodiments, when fabricating a superconducting impedance transformation parametric amplifier, wire bonding is performed to connect the core wire of a microwave connector externally fixed to the top surface of the sample box. The required length of wire and the number of parallel connections are determined. This ensures that the combined structure of these wires and pads has a characteristic impedance close to the impedance of the environment. This reduces unwanted reflections between the environment and the amplifier, improving its impedance environment. At the same time, the bulk metal of the sample box is also connected to a large metal film representing the earth on the chip using a large number of wires, ensuring good grounding and achieving durability for the superconducting impedance transformation parametric amplifier.

[0085] Referring to FIG. 8, FIG. 8 is a schematic diagram illustrating the use of a superconducting impedance transparametric amplifier in an embodiment of the present application. A target port for accessing a pump signal is set for the superconducting impedance transparametric amplifier. The target port is used to determine the operating point of the superconducting impedance transparametric amplifier. The center frequency of the superconducting impedance transparametric amplifier can be determined through the target port (the center frequency is determined based on the microwave signal strength reflected by the port, i.e., the frequency corresponding to the smallest reflection strength is set as the center frequency). Specifically, when used in conjunction with reading a qubit chip, the read signal passing through the bit chip is introduced into the superconducting impedance transparametric amplifier described in the embodiment of the present application via a circulator. The amplified reflected signal is separated from the input signal by the circulator. After undergoing two-stage and three-stage amplification by cryogenic and room-temperature amplifiers, the state of the qubit is analyzed and determined by room-temperature electronics. In addition to input and output ports, the superconducting impedance transparametric amplifier also has a port for accessing the pump signal. Generally, the DC bias and microwave drive must be mixed through a bias device before being connected to the port. The port here refers to the pump input port required for amplifier operation, not the operating port of the input signal. By scanning the DC bias appropriately, the operating point of the superconducting impedance transparametric amplifier can be determined. By scanning the DC bias, the amplifier's operating center frequency can be changed to determine the operating point according to the microwave frequency that needs to be amplified. By applying a driving microwave, the superconducting impedance transparametric amplifier achieves amplification. The appropriate driving microwave here refers to a microwave that can achieve sufficient gain without generating significant heat or noise.

[0086] 9, which is a schematic diagram of the test results of the superconducting impedance transparametric amplifier in the embodiment of the present application. The maximum available bandwidth of amplifiers realizing parametric amplification function in the related art is only about 600 MHz. However, as shown in FIG. 9, the peak available bandwidth of the superconducting impedance transparametric amplifier provided in the embodiment of the present application is 1 GHz, and the performance of the superconducting impedance transparametric amplifier is better, while the loss of the superconducting impedance transparametric amplifier is reduced. In the process of increasing the maximum available bandwidth of the superconducting impedance transparametric amplifier shown in FIG. 9 from 5500 GHz to 7500 GHz, the maximum loss value of the superconducting impedance transparametric amplifier is 24 dB, and at 7500 GHz, it is reduced to 8 dB.

[0087] In this application, the center wavelength parameters, gain parameters, and bandwidth parameters of the superconducting impedance transparametric amplifier are determined based on the usage environment parameters of the quantum chip; the impedance value of the impedance transformation line of the superconducting impedance transparametric amplifier and the capacitance value of the amplifier are calculated based on the wavelength parameters, gain parameters, and bandwidth parameters; the linewidth size of the coplanar waveguide of the superconducting impedance transparametric amplifier is calculated based on the impedance value of the impedance transformation line; the stub size of the superconducting impedance transparametric amplifier is calculated based on the impedance value of the impedance transformation line and the capacitance value of the amplifier; and the structural parameters of the superconducting impedance transparametric amplifier are determined based on the linewidth size and stub size, thereby realizing the following 1) and 2). 1) The method for determining a superconducting impedance transparametric amplifier provided by the present application can better improve the performance of the superconducting impedance transparametric amplifier and reduce the loss of the superconducting impedance transparametric amplifier; 2) At the same time, by utilizing the structure of the superconducting impedance transparametric amplifier, the yield in the production of the superconducting impedance transparametric amplifier can be improved and the production cost can be reduced, which is favorable for the large-scale popularization of superconducting quantum chips.

[0088] The above description is only an example of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and scope of the present application should be included in the scope of protection of the present application.

Claims

1. 1. A method for determining a superconducting transimpedance parametric amplifier implemented by electronic equipment, comprising: determining a center wavelength parameter, a gain parameter, and a bandwidth parameter of the superconducting transimpedance parametric amplifier based on the usage environment parameters of the quantum chip; determining an impedance value of an impedance transformation line of the superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier using the center wavelength parameter, the gain parameter, and the bandwidth parameter as constraints; calculating a line width size of the coplanar waveguide of the superconducting impedance transformation parametric amplifier based on the impedance value of the impedance transformation line; calculating a stub size of the superconducting transimpedance parametric amplifier based on the impedance value of the impedance transformation line and the capacitance value of the amplifier; determining structural parameters of the superconducting impedance transparametric amplifier based on the line width size and the stub size.

2. and further comprising a step of adjusting a shape of the coplanar waveguide of the superconducting impedance transformation parametric amplifier to a curved state when the impedance value of the impedance transformation line decreases.

2. The method for determining a superconducting transimpedance parametric amplifier according to claim 1.

3. calculating a room temperature resistance value of a Josephson junction of the superconducting transimpedance parametric amplifier based on a capacitance value of the amplifier and a center frequency of the superconducting transimpedance parametric amplifier, the room temperature resistance value being used to measure a qubit state.

3. The method for determining a superconducting transimpedance parametric amplifier according to claim 2.

4. setting a target port for the superconducting transimpedance parametric amplifier to which a pump signal is to be accessed, the target port being used to determine an operating point of the superconducting transimpedance parametric amplifier; 2. The method for determining a superconducting transimpedance parametric amplifier according to claim 1.

5. 1. A determination apparatus for a superconducting impedance transparametric amplifier, comprising: a signal transmission module configured to determine a center wavelength parameter, a gain parameter, and a bandwidth parameter of the superconducting transimpedance parametric amplifier based on a usage environment parameter of the quantum chip; a simulation design module configured to determine an impedance value of an impedance transformation line of the superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier using the center wavelength parameter, the gain parameter, and the bandwidth parameter as constraints; The simulation design module is configured to calculate a line width size of a coplanar waveguide of the superconducting impedance transformation parametric amplifier based on an impedance value of the impedance transformation line; the simulation design module is configured to calculate a stub size of the superconducting impedance transformation parametric amplifier based on an impedance value of the impedance transformation line and a capacitance value of the amplifier; The apparatus for determining a superconducting transimpedance parametric amplifier, wherein the simulation design module is configured to determine structural parameters of the superconducting transimpedance parametric amplifier based on the linewidth size and the stub size.

6. the simulation design module is configured to adjust a shape of the coplanar waveguide of the superconducting impedance transformation parametric amplifier to a curved state when an impedance value of the impedance transformation line decreases; 6. The apparatus for determining a superconducting transimpedance parametric amplifier according to claim 5.

7. the simulation design module is configured to calculate a room temperature resistance value of a Josephson junction of the superconducting transimpedance parametric amplifier based on a capacitance value of the amplifier and a center frequency of the superconducting transimpedance parametric amplifier, the room temperature resistance value being used to measure a qubit state.

6. The apparatus for determining a superconducting transimpedance parametric amplifier according to claim 5.

8. the simulation design module is configured to set a target port for the superconducting transimpedance parametric amplifier to access a pump signal, the target port being used to determine an operating point of the superconducting transimpedance parametric amplifier; 8. A device for determining a superconducting transimpedance parametric amplifier according to any one of claims 5 to 7.

9. a superconducting transimpedance parametric amplifier, the superconducting transimpedance parametric amplifier including an impedance converter and a Josephson parametric amplifier, the impedance converter and the Josephson parametric amplifier being integrated on the same quantum chip; the impedance transformer includes a coplanar waveguide, the length of the coplanar waveguide being ½ wavelength of the center frequency of the Josephson parametric amplifier; A superconducting transimpedance parametric amplifier, wherein the Josephson parametric amplifier includes a stub, the length of the stub matching a capacitance value of the superconducting transimpedance parametric amplifier.

10. An electronic device, a memory for storing computer-executable instructions; a processor that, when executing computer-executable instructions stored in the memory, implements the method for determining a superconducting transimpedance parametric amplifier according to any one of claims 1 to 4.

11. A computer program that causes a computer to execute the method for determining a superconducting impedance transparametric amplifier according to any one of claims 1 to 4.

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