CN115828823B

CN115828823B - Layout information output method and device for reading cavity and filter in superconducting quantum chip

Info

Publication number: CN115828823B
Application number: CN202211362545.8A
Authority: CN
Inventors: 王宇轩; 卢晨; 成恩宏; 晋力京
Original assignee: Beijing Baidu Netcom Science and Technology Co Ltd
Current assignee: Beijing Baidu Netcom Science and Technology Co Ltd
Priority date: 2022-11-02
Filing date: 2022-11-02
Publication date: 2023-07-21
Anticipated expiration: 2042-11-02
Also published as: CN115828823A

Abstract

The disclosure provides a layout information output method and device of a reading cavity and a filter in a superconducting quantum chip, relates to the technical field of quantum computing, and particularly relates to the technical field of superconducting quantum chips. The specific implementation scheme is as follows: acquiring target frequency information and target quality factor information of M reading combination devices in the quantum chip, wherein the M reading combination devices share one reading line to read information of quantum bits in the quantum chip; based on the target frequency information and the target quality factor information, respectively determining first layout information corresponding to each reading combination device, wherein the first layout information comprises first length information of the reading combination device and first coupling length information between a reading cavity and a filter in the reading combination device; based on the first target layout, the target frequency information and the target quality factor information, the first length information of each reading combination device is adjusted to obtain the second length information of each reading combination device; and outputting the second layout information.

Description

Layout information output method and device for reading cavity and filter in superconducting quantum chip

Technical Field

The disclosure relates to the technical field of quantum computing, in particular to the technical field of superconducting quantum chips, and specifically relates to a layout information output method and device of a reading cavity and a filter in a superconducting quantum chip.

Background

A complete superconducting quantum chip comprises a plurality of core functional modules, such as a reading module, a wiring module, a physical bit, a coupling module and the like. The reading module is used for reading information of the quantum bit, and is a very important part of the superconducting quantum chip.

The reading module can comprise a reading cavity, a filter and a reading line, and in order to ensure that the quantum bit can be read quickly and with high fidelity and has longer coherence life, the reading cavity and the filter are required to be subjected to layout design so as to achieve specific performance parameter indexes.

At present, layout parameters of a reading module in a superconducting quantum chip are usually verified through simulation according to experience or as a black box, and iterated for a plurality of times until design indexes are reached.

Disclosure of Invention

The present disclosure provides a layout information output method and device for a read cavity and a filter in a superconducting quantum chip.

According to a first aspect of the present disclosure, there is provided a layout information output method of a read cavity and a filter in a superconducting quantum chip, including:

Acquiring target frequency information and target quality factor information of M reading combination devices in a quantum chip, wherein the M reading combination devices share one reading line to read information of quantum bits in the quantum chip, and the reading combination devices comprise a reading cavity and a filter, and M is an integer larger than 1;

based on the target frequency information and the target quality factor information, respectively determining first layout information corresponding to each reading combination device, wherein the first layout information comprises first length information of the reading combination device and first coupling length information between a reading cavity and a filter in the reading combination device;

adjusting the first length information of each reading combination device based on a first target layout, the target frequency information and the target quality factor information to obtain second length information of each reading combination device, wherein the first target layout is a layout of the reading combination device and the reading line, and the coupling length between a reading cavity and a filter in the first target layout is the length indicated by the first coupling length information;

outputting second layout information, wherein the second layout information comprises third length information of each reading combination device and first coupling length information between a reading cavity and a filter in each reading combination device, and the third length information is determined based on the second length information.

According to a second aspect of the present disclosure, there is provided a layout information output device of a read cavity and a filter in a superconducting quantum chip, including:

the device comprises an acquisition module, a control module and a control module, wherein the acquisition module is used for acquiring target frequency information and target quality factor information of M reading combination devices in a quantum chip, the M reading combination devices share one reading line to read information of quantum bits in the quantum chip, the reading combination devices comprise a reading cavity and a filter, and M is an integer larger than 1;

the determining module is used for respectively determining first layout information corresponding to each reading combination device based on the target frequency information and the target quality factor information, wherein the first layout information comprises first length information of the reading combination device and first coupling length information between a reading cavity and a filter in the reading combination device;

the first adjusting module is used for adjusting the first length information of each reading combination device based on a first target layout, the target frequency information and the target quality factor information to obtain second length information of each reading combination device, wherein the first target layout is a layout of the reading combination device and the reading line, and the coupling length between a reading cavity and a filter in the first target layout is the length indicated by the first coupling length information;

The output module is used for outputting second layout information, the second layout information comprises third length information of each reading combination device and first coupling length information between a reading cavity and a filter in each reading combination device, and the third length information is determined based on the second length information.

According to a third aspect of the present disclosure, there is provided an electronic device comprising:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein,,

the memory stores instructions executable by the at least one processor to enable the at least one processor to perform any one of the methods of the first aspect.

According to a fourth aspect of the present disclosure, there is provided a non-transitory computer-readable storage medium storing computer instructions for causing a computer to perform any of the methods of the first aspect.

According to a fifth aspect of the present disclosure, there is provided a computer program product comprising a computer program which, when executed by a processor, implements any of the methods of the first aspect.

The technology solves the problem that the layout design of the reading cavity and the filter in the superconducting quantum chip is difficult, and improves the layout design efficiency of the reading cavity and the filter in the superconducting quantum chip.

It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the disclosure, nor is it intended to be used to limit the scope of the disclosure. Other features of the present disclosure will become apparent from the following specification.

Drawings

The drawings are for a better understanding of the present solution and are not to be construed as limiting the present disclosure. Wherein:

FIG. 1 is a flow chart of a method of outputting layout information of a read cavity and a filter in a superconducting quantum chip according to a first embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a complete layout structure of a quantum chip;

FIG. 3 is a schematic diagram of a reading device in a serpentine configuration;

FIG. 4 is a schematic diagram of a joint layout structure based on read cavities, filters and read lines;

FIG. 5 is a schematic diagram of a joint layout structure based on filters and read lines;

FIG. 6 is a flow diagram of a specific example provided by the present disclosure;

fig. 7 is a schematic structural diagram of a layout information output device of a read cavity and a filter in a superconducting quantum chip according to a second embodiment of the present disclosure;

fig. 8 is a schematic block diagram of an example electronic device used to implement embodiments of the present disclosure.

Detailed Description

Exemplary embodiments of the present disclosure are described below in conjunction with the accompanying drawings, which include various details of the embodiments of the present disclosure to facilitate understanding, and should be considered as merely exemplary. Accordingly, one of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the present disclosure. Also, descriptions of well-known functions and constructions are omitted in the following description for clarity and conciseness.

First embodiment

In this embodiment, the layout information output method of the reading cavity and the filter in the superconducting quantum chip relates to the technical field of quantum computing, in particular to the technical field of superconducting quantum chips, and can be widely applied to the layout design scene of the superconducting quantum chip. The layout information output method of the reading cavity and the filter in the superconducting quantum chip of the embodiment of the disclosure can be executed by the layout information output device of the reading cavity and the filter in the superconducting quantum chip of the embodiment of the disclosure. The layout information output device of the reading cavity and the filter in the superconducting quantum chip of the embodiment of the disclosure can be configured in any electronic equipment to execute the layout information output method of the reading cavity and the filter in the superconducting quantum chip of the embodiment of the disclosure.

The quantum chip can be a superconducting quantum chip, and is one of quantum computing hardware platforms with prospect due to the advantages of flexible design, high quantum gate operation speed, long decoherence time and the like of the quantum chip based on a superconducting circuit.

One of the key technical bases for developing superconducting quantum chips is the layout design of the superconducting quantum chips. With the need of solving the related complex problems and pursuing the performance parameters of the chip, the number of target qubits in the superconducting quantum chip is increased, and each module is more integrated and more complex. The problem that this produced is how to rationalize the module layout of quantum chip and how to solve the iteration cycle overlength of chip design, this just presents the challenge to superconducting quantum chip's layout design, consequently optimizes layout design, promotes the necessity and the urgency of layout iteration efficiency and stands out day by day.

The superconducting quantum chip may include a plurality of core functional modules, such as a read module, a wiring module, a physical bit, a coupling module, and the like. The read module is a very important part of the superconducting quantum chip, and is one of the modules with the largest occupied internal space, and the parameters and layout of each device need to be carefully designed, so that in the design of the superconducting quantum chip, the design of the read module for the quantum bit is particularly important. The performance parameter index of the device mainly focuses on the frequency and the quality factor Q value of the core device, wherein the frequency is a characteristic parameter of the device, and the Q value influences the reading efficiency of the reading module and the service life of the qubit.

The read module may comprise three parts: a read cavity, a filter and a read line. The reading cavity and the quantum bit are coupled in a dispersing way to generate frequency shift, so that indirect measurement of the quantum bit is realized. In particular, the reading cavity is directly coupled with the superconducting qubit, has a larger frequency difference to form dispersion coupling and generates dispersion translationWherein delta is _qr Is the amount of frequency mismatch, g, of the qubit and the read cavity _qr Is the coupling strength of the qubit to the read cavity. Thus, the state of the qubit can be indirectly measured by observing the dispersion shift of the read cavity frequency.

Dispersive coupling protects the decoherence time of the qubit to some extent, but a reading cavity coupled to the external environment inevitably gives dissipation to the qubit. Without a filter, the dissipation ratio Γ of the qubit _q Represented by the following formula (1).

Wherein, kappa _r The device is a dissipation ratio of a reading cavity, and the Q value of the device is inversely proportional to the dissipation ratio of the device, so that the coupling strength of the device and an external dissipation environment is reflected.

In a quantum chip, it is necessary to raise the Q value of a qubit as much as possible to increase the coherence time of the qubit, and therefore, it is necessary to reduce the dissipation rate κ of the read cavity _r Or coupling strength g, which however reduces the reading efficiency of the qubit.

In order to reduce the dissipation of the qubit and simultaneously maintain higher reading efficiency, a filter is usually added between the reading line and the reading cavity, the frequency of the filter is very close to the frequency of the reading cavity, a conducting band taking the frequency of the reading cavity and the frequency of the filter as the center is formed, the filter can shield noise of the external environment, the rapid measurement is carried out at the frequency of the reader, meanwhile, the noise at the frequency of the qubit is isolated, and the coherence time of the qubit is improved. In addition, the reading line is connected with an external measurement and control system to input and output reading pulse signals.

In order to ensure that the quantum bit can be read quickly and with high fidelity and has longer coherent service life, accurate layout design is required for a reading cavity and a filter so that the reading cavity and the filter reach specific performance parameter indexes.

Considering that the dissipation of the read cavity comes entirely from the coupling with the filter after the filter is newly added, the dissipation transfer formula of the filter-read cavity is expressed by the following formula (2).

Wherein Γ is _r For the dissipation ratio of the read chamber, κ _f For filter dissipation ratio due to coupling with read line g _rf To read the coupling strength of the cavity and the filter, delta _rf To read the frequency difference between the cavity and the filter. The above equation shows that the Q value of the reading cavity depends on the coupling strength and the frequency difference of the two devices in addition to the Q value of the filter, and the Q value of the reading cavity is positively correlated with the frequency difference of the two devices.

In equation (2), since the reading cavity and the filter have very close frequencies, the frequency difference Δ between the two devices _rf Coupling strength g _rf Are not negligible in the same order. Because of the coupling effect between the reading cavity and the filter, the frequency and the Q value of the filter cannot be independently adjusted, and the performance index requirement can be met by repeated iteration.

In order to design the layout of the reading cavity and the filter to reach specific frequency and Q value indexes, the frequency is usually adjusted by adjusting the length of the two devices, and the coupling strength of the two devices is adjusted by adjusting the coupling length between the two devices, so that the Q value of the reading cavity is adjusted. However, the frequency and the coupling strength of the two devices are not mutually independent, but are pulled to be transmitted to the whole body, so that the iteration process is too complex, and the requirement can be finally met by repeated attempts, thereby causing low layout design efficiency.

In addition, in practice, in order to save the read lines and optimize the chip layout space, a multiplexing read scheme is generally adopted, i.e. the reading of a plurality of qubits shares one read line, each qubit has a respective independent read cavity and filter, their frequencies are different from each other to avoid the crosstalk of the reading, the quantum chip layout of the multiplexing read scheme is shown in fig. 2, which illustrates only one set of read cavities and filters, and the other sets of read cavities and filters can be deployed in the same manner.

Therefore, multiple groups of reading cavities and filter layouts corresponding to different quantity sub-bits are required to be designed independently, and the parameters required to be designed are too many, so that the difficulty in designing the reading cavities and the filter layouts is increased. The difficulty presented is how to efficiently and flowingly design multiple sets of read cavities and filter layouts in multiplexed reads to achieve fast and high fidelity read performance.

The purpose of this embodiment is that: in multiplexing reading, parameters requiring design iteration are reduced by fixing the coupling lengths of a plurality of groups of reading cavities and filters, and the frequencies of the reading cavities and the filters and the frequency difference of the reading cavities and the filters are regulated by regulating the lengths of the two devices, so that the purpose of independently regulating the frequencies and the Q values of the two devices is achieved, and the layout design flow of a rapid reading module is realized.

The following describes the programming flow of the layout design of the reading cavity and the filter in the present embodiment in detail.

As shown in fig. 1, the present disclosure provides a layout information output method of a read cavity and a filter in a superconducting quantum chip, including the following steps:

step S101: the method comprises the steps of obtaining target frequency information and target quality factor information of M reading combination devices in a quantum chip, wherein the M reading combination devices share one reading line to read information of quantum bits in the quantum chip, and the reading combination devices comprise a reading cavity and a filter.

Wherein M is an integer greater than 1.

In this step, the read-out combination device may comprise a read-out cavity and a filter, the quantum chip employing a multiplexed read-out scheme, i.e. the reading of a plurality of qubits sharing one read-out line, each qubit having a respective independent read-out cavity and filter. Correspondingly, the M reading combination devices share one reading line to read the information of M quantum bits in the quantum chip. Both the read chamber and the filter may be serpentine in configuration as shown in fig. 3.

The target frequency information may include target frequencies of M read cavities and M filters, which may be eigenfrequencies of the read devices (read cavities, filters) of the desired design layout, which are controlled by the frequency of the qubits in the quantum chip and the number of multiplexes of the read lines.

For example, on the premise that the quantum bit and the reading cavity meet the dispersion coupling, the target frequencies of the reading cavities and the filters of each group in the multiplexing reading scheme are allocated. The frequency difference between the quantum bit and the reading cavity is required to be larger than 1GHz in the dispersion coupling, the target frequencies of the reading cavity corresponding to the same quantum bit and the filter can be set to be the same, and the target frequencies between the reading cavity corresponding to a plurality of groups of quantum bits and the filter can be different by 50-100MHz.

The acquisition mode of the target frequency information includes, but is not limited to: the target frequency of the filter is determined manually or automatically according to the frequency of the qubit and the multiplexing quantity control of the read line.

The target quality factor information may include a first target quality factor of the M filters and a second target quality factor of the M read cavities, where the target quality factor may be a quality factor of the read device of the desired design layout, and the target quality factor determines a dissipation ratio of the read device, and the two are in an inverse relationship.

The first target quality factor is used to indicate the crosstalk prevention performance of the filter at the time of information reading, and after the filter is added,on the premise of keeping the dissipation rate of the reading cavity, namely the reading efficiency unchanged, the dissipation rate gamma of the quantum bit _q Can be significantly reduced by a factor F represented by the following formula (3).

Wherein, kappa _f Is the dissipation ratio of the filter (inversely proportional to the Q value of the filter), delta _qr Is the amount of detuning of the qubit from the read cavity, F is an amount much smaller than 1, so the presence of the filter can significantly reduce the qubit dissipation ratio while maintaining a high read efficiency.

The second target quality factor is used for indicating the reading efficiency of the reading cavity during information reading.

The first target quality factors of the M filters may be set to be the same, e.g., set to 100, and the second target quality factors of the M read cavities may be set to be the same, e.g., set to 1000.

The obtaining manner of the target quality factor information includes, but is not limited to: and according to the quantum chip layout, manually or automatically determining a first target quality factor of the filter and a second target quality factor of the reading cavity.

Step S102: and respectively determining first layout information corresponding to each reading combination device based on the target frequency information and the target quality factor information, wherein the first layout information comprises first length information of the reading combination device and first coupling length information between a reading cavity and a filter in the reading combination device.

In this step, the first length information may include length information of the reading cavity and length information of the filter, the length information indicating a total length of the reading cavity and a total length of the filter, respectively, indicating an initial length of the reading device. The frequency of the reading device is related to the length of the reading device, and the frequency performance index of the reading device can be achieved through the length layout design of the reading device.

The first coupling length information indicates the coupling length between the reading cavity and the filter, the quality factor of the reading device is related to the length of the reading device and the coupling length between the reading devices, and the quality factor performance index of the reading device can be achieved through the length of the reading device and the layout design of the coupling length. In the layout design for M reading combination devices, the coupling lengths between the reading cavities and the filters may be the same or different, which is not particularly limited herein.

The first length information of the read combining device and the first coupling length information between the read cavity and the filter in the read combining device can be uniformly determined by combining the target frequency information and the target quality factor information. And carrying out electromagnetic simulation on the joint layout of the reading cavity, the filter and the reading line in an electromagnetic simulation mode, and iteratively adjusting the lengths of the reading cavity and the filter and the coupling length between the reading cavity and the filter to obtain first length information and first coupling length information.

The first length information and the first coupling length information may also be determined based on the target frequency information and the target quality factor information, respectively. For example, first length information is determined based on the target frequency information, and based on the first length information and the target quality factor information, first coupling length information is determined. Therefore, the layout iteration process and the layout design difficulty can be simplified, and the efficiency and the accuracy of the quantum chip layout design are improved.

The first coupling length information between the reading cavity and the filter in each reading and combining device may be determined separately, or the first coupling length information between the reading cavity and the filter in one reading and combining device may be determined, and then the coupling lengths between the reading cavities and the filters in the M reading and combining devices are kept uniform and fixed, that is, uniform is the coupling length indicated by the first coupling length information, which is not limited specifically herein.

In addition, the first layout information may further include a coupling length between each filter and the read line, and in an alternative embodiment, the filter may be subjected to electromagnetic simulation based on a joint layout of the filter and the read line, and the Q value of the filter may be iterated by adjusting the coupling length of the filter and the read line. And if the error between the simulated Q value and the first target quality factor exceeds +/-10%, iterating according to the principle that the coupling length is longer and the Q value is smaller, so as to obtain the coupling length matched with the first target quality factor.

Step S103: and adjusting the first length information of each reading combination device based on a first target layout, the target frequency information and the target quality factor information to obtain second length information of each reading combination device, wherein the first target layout is a layout of the reading combination device and the reading line, and the coupling length between a reading cavity and a filter in the first target layout is the length indicated by the first coupling length information.

The method comprises the step of carrying out fine adjustment on the length of a reading device based on target frequency information and target quality factor information under a first target layout so as to improve the design accuracy of a quantum chip layout.

Specifically, the first target layout may be a layout of the reading combination device and the reading line, that is, a joint layout of "reading cavity+filter+reading line", as shown in fig. 4. The coupling length between the reading cavity and the filter in the first target layout can be the length indicated by the first coupling length information, namely, in the process of finely adjusting the length of the reading device, the coupling length between the reading cavity and the filter can be fixed, namely, the coupling strength between the reading cavity and the filter is fixed, so that parameters needing design iteration can be reduced, the design flow of the quantum chip layout is simplified, and the quantum chip layout meeting the target frequency information and the target quality factor information is iterated efficiently.

The frequency of the reading cavity and the filter can be obtained by carrying out electromagnetic simulation on the reading combined device based on the first target layout, the frequency difference between the reading cavity and the filter can be determined based on the frequency of the reading cavity and the filter (as can be known from the formula (2), the frequency difference can influence the Q value of the reading cavity), so that the frequency of the reading cavity and the filter and the quality factor of the reading cavity can be finely adjusted by iteratively adjusting the first length information on the basis of the first length information and the first coupling length information, and the second length information which is matched with the target frequency information and the second target quality factor of the reading cavity can be obtained.

In this way, the coupling length (i.e. the fixed coupling strength) between the filter and the reading cavity can be fixed by inspiring from the dissipation transmission formula of the filter-reading cavity, namely the formula (2), and the frequency of the two devices and the frequency difference of the two devices can be adjusted by adjusting the lengths of the reading cavity and the filter, so that the purpose of independently adjusting the Q value of the reading cavity can be achieved by adjusting the lengths of the reading cavity and the filter.

Step S104: outputting second layout information, wherein the second layout information comprises third length information of each reading combination device and first coupling length information between a reading cavity and a filter in each reading combination device, and the third length information is determined based on the second length information.

In this step, in the case of determining the second layout information of the reading cavity and the filter, the second layout information may be output. The second layout information may include first coupling length information and third length information determined based on the second length information. In addition, second coupling length information indicating a coupling length between the filter and the read line may be further included in the second layout information. Correspondingly, the layout design of the reading cavity and the filter can be performed based on the output second layout information, so that the design of the quantum chip layout is performed, and the accuracy and the efficiency of the design of the quantum chip layout are improved.

In an alternative embodiment, the second length information may be determined as the third length information.

In another alternative embodiment, the second length information may be verified by simulation based on the complete layout of the quantum chip, so as to verify whether the frequencies of the reading cavity and the filter and the quality factors of the reading cavity are within a preset precision under the second length information, and if the quality factors of the reading cavity are not within the preset precision, the lengths of the reading cavity and the filter are iteratively adjusted based on the second length information and the first coupling length information, so as to obtain third length information. The frequency information of the reading combination device is closer to and matched with the target frequency information, and the quality factor of the reading cavity is closer to and matched with the second target quality factor than the second length information.

In this embodiment, in the multiplexing reading, by fixing the coupling lengths of the multiple groups of reading cavities and the filters, the parameters that need to be iterated in design can be reduced, and the frequency difference is finely adjusted only by adjusting the initial lengths of the two reading devices, so as to achieve fine adjustment of the frequencies of the two reading devices and the Q values of the reading cavities, thereby realizing a rapid design flow of the reading module. Moreover, the method can fill the blank of iteration flow of the read module design, and the flow design can efficiently iterate out the quantum chip layout meeting the target performance parameters, thereby greatly improving the layout design efficiency and accuracy of the quantum chip.

Optionally, the step S102 specifically includes:

determining first length information of each reading combination device based on the target frequency information;

determining second coupling length information between the filter and the reading line in each reading combination device based on a second target layout and a first target quality factor of the filter in the target quality factor information, wherein the second target layout is a layout of the filter and the reading line, and the length of the filter in the second target layout is the length indicated by the length information of the filter in the first length information;

And determining the first coupling length information based on a third target layout and the target quality factor information, wherein the third target layout is a layout of a reading combination device and a reading line, and in the third target layout, the length corresponding to the reading combination device is the length indicated by the first length information, and the coupling length between the filter and the reading line is the length indicated by the second coupling length information.

In the present embodiment, the first length information and the first coupling length information are determined based on the target frequency information and the target quality factor information, respectively.

Specifically, the reading cavity and the filter may adopt a configuration of a quarter-wavelength coplanar waveguide, wherein one end is an open circuit, the other end is a short circuit, and the frequency and the length of the reading device are in a relation shown in the following formula (4).

Where f is the frequency of the coplanar waveguide, l is the total length of the waveguide, c is the speed of light, ε _eff Is the equivalent dielectric coefficient of a coplanar waveguide.

In an alternative embodiment, for each reading device, the equivalent dielectric coefficient under its coplanar waveguide may be calculated, and based on the equivalent dielectric coefficient, the length information of the reading device matching the target frequency is determined.

In another alternative embodiment, the length information of each reading device may be obtained by performing electromagnetic simulation on the reading device based on the target frequency of each reading device in the target frequency information in an electromagnetic simulation manner.

The reading device can be subjected to isolated device simulation through electromagnetic simulation software, so that length information of the reading device matched with the target frequency is obtained. In this embodiment, the length indicated by the first length information is approximately the length of the reading device, that is, the total length of the reading device can be adjusted based on the layout of the reading module and/or the layout refinement of the quantum chip, so that the total length of the reading device can be adjusted from rough to refined, on one hand, the difficulty in adjusting the total length of the reading device can be reduced, and on the other hand, the accuracy and efficiency for adjusting the total length of the reading device in the quantum chip layout can be improved.

For each reading combination device, on the basis of determining the first length information, the filter can be subjected to electromagnetic simulation based on a combined layout of the filter and the reading line (as shown in fig. 5, the combined layout is a second target layout, the length of the filter in the second target layout is the length indicated by the length information of the filter), and the Q value of the filter is iterated by adjusting the coupling length of the filter and the reading line. And if the error between the simulated Q value and the first target quality factor exceeds +/-10%, iterating according to the principle that the coupling length is longer and the Q value is smaller, so as to obtain second coupling length information matched with the first target quality factor.

And then, on the basis of determining the first length information and the second coupling length information, carrying out electromagnetic simulation on the read combination device based on a group of read cavity, filter and read line joint layout (namely a third target layout), and iteratively adjusting the coupling length of the read cavity and the filter in the joint layout based on a second target quality factor so as to determine the first coupling length information, wherein the quality factor obtained by the simulation of the first coupling length information is matched with the second target quality factor.

The length corresponding to the reading combination device in the third target layout is the length indicated by the first length information, namely the length of the reading cavity is the length indicated by the length information of the reading cavity in the first length information, the length of the filter is the length indicated by the length information of the filter in the first length information, and the coupling length between the filter and the reading line is the length indicated by the second coupling length information.

Therefore, the layout information iterative design is carried out by firstly determining the initial length of the reading cavity and the filter, then determining the coupling length between the filter and the reading line and then determining the sequence of the coupling length between the reading cavity and the filter, so that the layout iterative process and the layout design difficulty can be simplified, and the efficiency and the accuracy of the quantum chip layout design can be improved.

Optionally, the first coupling length information between the reading cavity and the filter in the M reading combination devices is the same.

In this embodiment, the coupling lengths between the reading cavities and the filters in the M reading combination devices are kept uniform and fixed, that is, the coupling lengths indicated by the first coupling length information are uniform, so that the layout design flow of the reading cavities and the filters can be simplified.

Optionally, for each of the first reading combination devices, the reading device is a reading cavity or a filter, the first reading combination device is any one of the M reading combination devices, the determining, based on the target frequency information, first length information of each reading combination device includes:

performing electromagnetic simulation on the reading device to obtain the change relation between the intrinsic frequency and the length information of the reading device;

determining an equivalent dielectric constant of the coplanar waveguide reading device based on the change relation;

determining first initial length information of the reading device based on the equivalent dielectric constant and a target frequency of the reading device in target frequency information of the first reading combination device, wherein the first length information comprises the first initial length information.

In this embodiment, the initial length of the reading device may be determined in the same manner for each reading device.

The reading device can be subjected to isolated device simulation through electromagnetic simulation software. By changing the total length of the reading device, the eigenfrequency of the reading device is obtained through simulation, so that a rough curve of the change of the eigenfrequency and the length of the reading device can be obtained.

The equivalent dielectric constant E of the coplanar waveguide reading device can be fitted according to the change curve of the frequency and the length _eff So that the equivalent dielectric constant E obtained based on the target frequency and the simulation _eff The approximate length of the reading device at the target frequency is obtained. The first initial length information of the reading device is determined in an electromagnetic simulation mode, and the determining process of the first length information can be simplified.

Optionally, the determining the first initial length information of the reading device based on the equivalent dielectric constant and the target frequency of the reading device in the target frequency information of the first reading combination device includes:

determining second initial length information based on the equivalent dielectric constant and the target frequency;

Performing electromagnetic simulation on the reading device based on the second initial length information to obtain a first frequency;

performing iterative adjustment on the second initial length information to obtain the first initial length information under the condition that the error between the first frequency and the target frequency is larger than a first preset threshold value;

and determining the second initial length information as the first initial length information under the condition that the error between the first frequency and the target frequency is smaller than or equal to the first preset threshold value.

In this embodiment, the second initial length information of the reading device may be determined by the above equation (4) based on the equivalent dielectric constant and the target frequency, and the second initial length information may be an approximate length of the reading device.

After obtaining the approximate length of the reading device, the simulation verification of the eigenfrequency of the isolated device can be performed on the reading device under the length. Electromagnetic simulation can be performed on the reading device under the length to obtain a first frequency corresponding to the length, and the convergence accuracy can be set at 2%, so that the layout design time is saved.

If the difference between the first frequency obtained by simulation verification and the target frequency is too large (for example, is larger than a first preset threshold value, for example, is different by 10%), the length of the reading device is iteratively adjusted on the basis of the second initial length information according to the inverse relation between the length and the frequency, so that the first initial length information is obtained. And if the difference value between the first frequency obtained by simulation verification and the target frequency is smaller than or equal to a first preset threshold value, determining the second initial length information as the first initial length information. The first preset threshold may be set according to actual situations, and is not specifically limited herein.

In this embodiment, by performing simulation verification on the approximate length of the reading device, and under the condition that the frequency obtained by the simulation verification is too far away from the target frequency, continuing to iteratively adjust the length of the reading device under the approximate length of the reading device, so that the length of the reading device reaches the preset precision, the accuracy of determining the length of the reading device can be improved, and the accuracy of layout design of the reading device can be improved.

It should be noted that, the iterative adjustment in this embodiment refers to performing electromagnetic simulation on the reading device on the basis of a layout to obtain relevant parameters (such as frequency and quality factor) of the reading device, comparing the relevant parameters with the target parameters, and if the errors of the relevant parameters and the target parameters do not reach the preset precision, continuing to adjust the layout information of the reading device until the adjusted layout information can enable the error between the relevant parameters and the target parameters of the reading device to reach the preset precision.

Optionally, the determining the second coupling length information between the filter and the read line in each read combination device based on the second target layout and the first target quality factor of the filter in the target quality factor information includes:

Performing electromagnetic simulation on a filter in each reading combination device based on a second target layout to obtain a first quality factor of the filter, wherein the first quality factor is matched with preset coupling length information between the filter and a reading line;

and iteratively adjusting the coupling length information between the preset filter and the reading line based on the first quality factor and the first target quality factor to obtain the second coupling length information, wherein the error between the quality factor matched with the second coupling length information and the first target quality factor is smaller than or equal to a second preset threshold value.

In this embodiment, for each reading combination device, based on determining the first length information, electromagnetic simulation may be performed on the filter in the reading combination device based on the second target layout of the filter and the reading line, so as to obtain a first quality factor of the filter, where the first quality factor is matched with the coupling length information between the preset filter and the reading line in the second target layout, that is, the first quality factor is obtained by simulating the coupling length information between the preset filter and the reading line.

And comparing the first quality factor with the first target quality factor, and when the error between the first quality factor and the first target quality factor is larger than a second preset threshold, iterating the Q value of the filter by adjusting the coupling length of the filter and the reading line according to the principle that the Q value is smaller as the coupling length is longer, until the error between the Q value obtained by simulation and the first target quality factor is smaller than or equal to the second preset threshold, such as +/-10%, so as to obtain second coupling length information matched with the first target quality factor.

The second preset threshold may be set according to actual situations, and is not specifically limited herein.

Optionally, the determining the first coupling length information based on the third target layout and the target quality factor information includes:

performing electromagnetic simulation on the reading combination device based on the third target layout to obtain a second quality factor of the reading cavity, wherein the second quality factor is matched with the preset coupling length information between the reading cavity and the filter;

and iteratively adjusting the coupling length information between the preset reading cavity and the filter based on the second quality factor and a second target quality factor of the reading cavity in the target quality factor information to obtain the first coupling length information, wherein an error between the quality factor matched with the first coupling length information and the second target quality factor is smaller than or equal to a third preset threshold value.

In this embodiment, for a group of reading combination devices, on the basis of determining the first length information and the second coupling length information, electromagnetic simulation may be performed on the reading combination devices based on the third target layout of the reading cavity, the filter and the reading line, so as to obtain a second quality factor of the reading cavity, where the second quality factor is matched with the coupling length information between the preset reading cavity and the filter in the third target layout, that is, the second quality factor is obtained by simulating the coupling length information between the preset reading cavity and the filter.

And comparing the second quality factor with a second target quality factor, and when the error between the second quality factor and the second target quality factor is larger than a third preset threshold, iterating the Q value of the reading cavity by adjusting the coupling length of the reading cavity and the filter according to the principle that the Q value is smaller as the coupling length is longer, until the error between the Q value obtained by simulation and the second target quality factor is smaller than or equal to the third preset threshold, such as +/-30%, so as to obtain first coupling length information matched with the second target quality factor.

The third preset threshold may be set according to practical situations, and is not specifically limited herein.

Therefore, on the basis of obtaining the coupling length between the reading cavity and the filter, the coupling length between the reading cavity and the filter in each group of reading combination devices can be unified and fixed, so that layout parameters needing design iteration are reduced.

Optionally, the step S103 specifically includes:

for each reading combination device, carrying out electromagnetic simulation on the reading combination device based on a first target layout to obtain a second frequency of a reading cavity and a third frequency of a filter, wherein the second frequency is matched with the length information of the reading cavity in the first length information, and the third frequency is matched with the length information of the filter in the first length information;

iteratively adjusting the first length information based on the second frequency, the third frequency, the target frequency of the reading cavity and the filter of the reading combination device in the target frequency information, and the target quality factor information to obtain second length information of the reading combination device;

the error between the frequency of the length information matching of the reading cavity in the second length information and the target frequency of the reading cavity is smaller than or equal to a fourth preset threshold value, the error between the frequency of the length information matching of the filter in the second length information and the target frequency of the filter is smaller than or equal to a fifth preset threshold value, and the error between the quality factor of the reading cavity matched with the second length information and the second target quality factor of the reading cavity in the target quality factor information is smaller than or equal to a sixth preset threshold value.

In this embodiment, on the basis of obtaining the first length information, electromagnetic simulation may be performed on the read combining device based on the first target layout (that is, the length of the read combining device in the first target layout is the length indicated by the first length information), so that the second frequency of the read cavity and the third frequency of the filter may be obtained.

And then, based on the second frequency, the third frequency, the target frequency of the reading cavity and the filter and the target quality factor information, iteratively adjusting the first length information to obtain the second length information of the reading combination device.

In an alternative embodiment, the frequency and the quality factor of the reading cavity may be combined to iteratively adjust the first length information, i.e. the first length information needs to be adjusted, so that the frequencies of the two reading devices and the quality factor of the reading cavity meet the preset accuracy at the same time.

In another alternative embodiment, the first length information may be iteratively adjusted based on frequency first, such that the error of the simulation frequency of the two reading devices and the target frequency is within a preset accuracy. And then, simulating the joint layout of the reading cavity, the filter and the reading line, and finely adjusting the respective lengths of the reading cavity and the filter to adjust the frequency difference between the two reading devices, so as to iterate the Q value of the reading cavity, and enabling the error between the Q value obtained by simulation and the second target quality factor to be within the preset precision.

The second frequency and the target frequency of the reading cavity, the third frequency and the target frequency of the reading cavity, and the quality factor obtained by the comparison simulation and the second target quality factor can be compared, and the first length information is iteratively adjusted based on the comparison error until the second length information is obtained. The error between the frequency of the length information matching of the reading cavity in the second length information (the matching refers to the frequency obtained by simulating the length information) and the target frequency of the reading cavity is smaller than or equal to a fourth preset threshold value, the error between the frequency of the length information matching of the filter in the second length information and the target frequency of the filter is smaller than or equal to a fifth preset threshold value, and the error between the quality factor of the reading cavity matched with the second length information and the second target quality factor of the reading cavity in the target quality factor information is smaller than or equal to a sixth preset threshold value.

The fourth preset threshold, the fifth preset threshold, and the sixth preset threshold may be set according to actual conditions, and are not particularly limited herein. It should be noted that, since the quality factor of the reading cavity is finely adjusted in this step, the quality factor obtained by simulation should be more accurate than the quality factor obtained by roughly adjusting the quality factor of the reading cavity only for the coupling length between the reading cavity and the filter, and thus, the sixth preset threshold may be smaller than the third preset threshold, for example, the sixth preset threshold may be set to 10%, and the third preset threshold may be set to 30%.

In this way, the frequency of the two reading devices and the quality factor of the reading cavity can be adjusted by performing iterative adjustment on the first length information.

Optionally, the iteratively adjusting the first length information based on the second frequency, the third frequency, the target frequency of the reading cavity and the filter of the reading combination device in the target frequency information, and the target quality factor information to obtain second length information of the reading combination device includes:

iteratively adjusting the first length information based on the second frequency, the third frequency and the target frequency of the reading cavity and the filter of the reading combination device in the target frequency information to obtain fourth length information of the reading combination device, wherein an error between the frequency matched with the length information of the reading cavity in the fourth length information and the target frequency of the reading cavity is smaller than or equal to the fourth preset threshold value, and an error between the frequency matched with the length information of the filter in the fourth length information and the target frequency of the filter is smaller than or equal to the fifth preset threshold value;

and iteratively adjusting the fourth length information based on a fourth target layout and the target quality factor information to obtain the second length information, wherein the fourth target layout is the layout of the reading combination device and the reading line, and in the fourth target layout, the coupling length between the reading cavity and the filter is the length indicated by the first coupling length information.

In this embodiment, the first length information may be iteratively adjusted based on the frequency first, so that the errors between the simulation frequencies and the target frequencies of the two reading devices are within a preset accuracy. And then, simulating the joint layout of the reading cavity, the filter and the reading line, and finely adjusting the respective lengths of the reading cavity and the filter to adjust the frequency difference between the two reading devices, so as to iterate the Q value of the reading cavity, and enabling the error between the Q value obtained by simulation and the second target quality factor to be within the preset precision. That is, by the process of iterative adjustment twice, independent adjustment of the frequencies of the two reading devices and the quality factor of the reading cavity is achieved.

Specifically, first, iterative adjustment of the first length information may be performed based on the first target layout, so as to finely adjust frequencies of the two reading devices, and obtain fourth length information.

Specifically, as the frequency of the device is changed due to the mutual coupling among the reading cavity, the filter and the reading line, the joint layout of the reading cavity, the filter and the reading line is simulated, and the simulation frequency of the two reading devices is more approximate to the target frequency relative to the frequency rough adjustment process of the reading devices by adjusting the respective lengths of the reading cavity and the filter.

If the simulation frequency of the device is different from the target frequency by more than 1%, the simulation frequency is adjusted according to the inverse relation between the frequency and the length of the device. It should be noted that the reading cavity and the filter length can be adjusted while the coupling length of the reading cavity and the filter and the coupling length of the filter and the reading line are kept unchanged, so that the Q values of the reading cavity and the filter are not changed greatly.

And then, carrying out iterative adjustment on the fourth length information based on the fourth target layout to finely adjust the quality factor of the reading cavity, so that the quality factor obtained by the simulation of the reading cavity is more similar to the second target quality factor, and the second length information is obtained.

Therefore, the frequency difference of the two reading devices can be finely adjusted by adjusting the lengths of the two reading devices, so that the independent adjustment of the frequencies and the Q values of the two reading devices is achieved, the layout design process of the reading module is simplified, the layout design flow of the reading module is rapidly realized, and the layout design efficiency and accuracy of the reading module are further improved.

Optionally, the performing iterative adjustment on the fourth length information based on the fourth target layout and the target quality factor information to obtain the second length information includes:

Performing electromagnetic simulation on the reading combination device based on a fourth target layout to obtain a third quality factor of a reading cavity in the reading combination device;

iteratively adjusting fourth length information based on the third quality factor, the second target quality factor and a predetermined first relation to obtain the second length information;

the first relation is a relation between a quality factor of the reading cavity and a frequency difference between the reading cavity and the filter in the reading combination device, and in the first relation, the quality factor of the reading cavity and the frequency difference between the reading cavity and the filter are positively correlated.

In this embodiment, the fourth target layout, which is the combined layout of the reading cavity, the filter, and the reading line, may be simulated to obtain the third quality factor.

And comparing the third quality factor with the second target quality factor, and when the error of the third quality factor and the second target quality factor exceeds a sixth preset threshold value, adjusting the frequency difference between the two reading devices by fine-adjusting the respective lengths of the reading cavity and the filter, and iterating the Q value of the reading cavity according to a first relation. The first relationship is that the Q of the reading cavity is positively correlated with the frequency difference between the two reading devices.

Optionally, the first relationship includes:

Wherein Γ is _r For the dissipation ratio of the read chamber, κ _f For filter dissipation ratio due to coupling with read line g _rf To read the coupling strength of the cavity and the filter, delta _rf For reading the frequency difference between the cavity and the filterThe first relationship further includes: the dissipation ratio of the read chamber is inversely related to the quality factor of the read chamber.

In the present embodiment, in the case of the present embodiment,in (2), the coupling length between the fixed reading cavity and the filter is fixed, i.e. the coupling strength, and fixed kappa _f In the case of a read chamber, the dissipation ratio is inversely proportional to the frequency difference between the read chamber and the filter, whereas the dissipation ratio of the read chamber is inversely proportional to the quality factor of the read chamber, and therefore the quality factor of the read chamber is positively correlated to the frequency difference between the read chamber and the filter.

Correspondingly, the method can be inspired from a dissipation transmission formula of the filter-reading cavity, theoretical guidance and clear design iteration directions are established, in the layout design iteration of the reading cavity and the filter, the coupling length between the reading cavity and the filter is fixed, and the frequency difference is finely adjusted by adjusting the lengths of the two reading devices, so that the fine adjustment of the frequency and the Q value of the two reading devices is achieved.

Optionally, before the step S104, the method further includes:

Performing electromagnetic simulation on the M reading combination devices based on a fifth target layout to obtain first frequency information and first quality factor information of the M reading combination devices, wherein the fifth target layout is a layout of a quantum chip, and in the fifth target layout, the coupling length between a reading cavity and a filter is the length indicated by the first coupling length information, and the lengths of the reading cavity and the filter in the reading combination devices are the length indicated by the second length information;

when the error between the first frequency information and the target frequency information is greater than a seventh preset threshold value, or the error between the first quality factor information and the target quality factor information is greater than an eighth preset threshold value, iteratively adjusting the second length information based on the second target quality factor and the first relation to obtain the third length information;

the first error is smaller than or equal to the error of the frequency information of the reading combination device matched with the second length information and the target frequency information, and the first error is the error of the frequency information of the reading combination device matched with the third length information and the target frequency information; and/or, the second error is smaller than or equal to the error of the quality factor information of the read combination device matched with the second length information and the target quality factor information, and the second error is the error of the quality factor information of the read combination device matched with the third length information and the target quality factor information.

In this embodiment, a plurality of groups of iterated read module layouts (including read cavities, filters and read lines) are integrated with the qubit and coupler layouts to form a complete layout (i.e., a fifth target layout), and as shown in fig. 2, fine electromagnetic simulation is performed on the complete layout to obtain first frequency information (including frequencies of the read cavities and the filters) and first quality factor information (including Q values of the read cavities and the filters) so as to verify whether the frequencies and the Q values of the read cavities and the filters reach target values.

The verification result needs to ensure that the errors of the reading cavity, the filter frequency and the target frequency are smaller than or equal to a seventh preset threshold value, if the errors are within +/-1%, the errors of the Q value and the target quality factor are smaller than or equal to an eighth preset threshold value, if the errors are within +/-10%, so that the design of the reading module is completed.

The seventh preset threshold and the eighth preset threshold may be set according to actual situations, and are not specifically limited herein. In general, the seventh preset threshold may be the same as the threshold of the error of the refinement adjustment frequency, and the eighth preset threshold may be the same as the threshold of the refinement adjustment quality factor.

If the verification result does not reach the target parameter and the error precision, the simulation precision needs to be integrally improved, for example, the simulation convergence condition is improved, the initial mesh division of the simulation setting is increased, on the basis of fixing the coupling length between the reading cavity and the filter on the basis of the second length information, and on the basis of the joint layout of the reading cavity, the filter and the reading line, fine iteration is performed on the second length information again according to the first relation so as to obtain third length information, so that the frequency information matched by the third length information (the frequency information matched by the second length information) is more similar to the target frequency information, and the quality factor information matched by the third length information (the quality factor information matched by the second length information) is more similar to the target quality factor information.

Optionally, the target frequency information is obtained by the following method:

the target frequency information is determined based on the frequency of the qubit and the multiplexing number of the read-out combination devices shared by the read-out lines.

In this embodiment, the target frequency information may be automatically determined according to the frequency of the qubit and the multiplexing number of the read combining devices shared by the read lines, so as to determine the target frequency information.

In an alternative implementation, the overall flow of this embodiment is shown in fig. 6, and the above steps are already described in detail, which is not described herein again.

The embodiment provides a design flow of a reading module in the complete and clear superconducting quantum chip, and particularly provides a specific scheme for iteration of the frequency and the Q value of a reading cavity and a filter, so that the method has strong practicability; in addition, the coupling length of a plurality of groups of reading cavities and filters is fixed in the multiplexing reading scheme, decoupling of the frequencies and the Q values of the two reading devices is achieved by adjusting the frequency difference between the reading cavities and the filters, and meanwhile parameters required to design iteration are greatly reduced, so that a rapid reading module design flow is achieved, and automation and flow of superconducting quantum chip layout design are facilitated.

In order to verify the effect of the scheme of the embodiment, the flow design scheme of the read cavity-filter layout provided by the embodiment can be applied to a read module layout design of read line 9-way multiplexing. Under the flow framework provided by the scheme of the embodiment, the read cavity and the filter layout which meet the requirements and are iterative and efficient are accurately designed, and the effectiveness and the advantages of the scheme of the embodiment are verified.

The first step: the read cavity, filter target frequency is determined.

Depending on the quantum chip design requirements, there may be the following initial parameters: the frequency range of the reading cavity is 4-8GHz; the qubit frequency is about 6GHz; the multiplexing number of the reading lines is 9; the target Q values of the read cavity and the filter are 1000 and 100. Therefore, the same frequencies of the same group of reading cavity-filters are set, the frequencies of the different groups of reading cavity-filters are different by 80MHz, and the frequencies are respectively: 4.74,4.82,4.90,4.98,5.06,5.14,5.22,5.30,5.38ghz.

And a second step of: the read cavity, filter initial length is determined.

Performing simulation of isolated elements on the reading cavity and the filter, fitting equivalent dielectric constants according to the frequency length relation, and further calculating to obtain that the initial lengths of the reading cavity are respectively (corresponding frequencies are from low to high): 7101 6997, 6880, 6760, 6680, 6560, 6440, 6330, 6210 μm; the initial filter lengths are (corresponding frequencies from low to high): 7728 7606, 7430, 7250, 7223, 7050, 6900, 6800, 6712 μm.

And a third step of: the filter Q value iterates.

The joint layout of the simulation filter and the reading line is used for iterating the Q value of the filter by adjusting the coupling length of the filter and the reading line, wherein the target Q value is 100, the error is set to be +/-20%, and the coupling lengths of 9 groups of filters and the reading line are respectively as follows: 1330 1300, 1260, 1240, 1218, 1190, 1180, 1150, 1130 μm.

Fourth step: the coupling length of the read cavity and the filter is fixed.

The joint layout of a group of reading cavities, filters and reading lines is simulated, the target Q value is 1000, the error is set to be +/-30%, the coupling length of the reading cavities and the filters is determined to be 400 mu m, and the coupling length is kept uniform and fixed in the layout of 9 groups of reading cavities and the filters.

Fifth step: the read cavity and filter frequencies are adjusted to the target frequency.

The joint layout of the reading cavity, the filter and the reading line is simulated, the lengths of the reading cavity and the filter are adjusted to adjust the frequency on the premise of not changing the coupling length, the specific mode of adjusting the lengths of the reading cavity and the filter is shown in the figure 4, namely, the length of the reading cavity can be adjusted by adjusting the length of the middle section of the reading cavity, and the length of the filter can be adjusted by adjusting the length of the tail section of the filter, so that 9 groups of reading cavities, the lengths of the filter and the corresponding simulation frequencies meeting the target frequency requirement can be iterated, and the simulation frequencies are shown in the following table 1.

TABLE 1 reading Chamber, length of Filter and Emulation frequency Table

Sixth step: and (5) iterating the Q value of the reading cavity.

And simulating the joint layout of the reading cavity, the filter and the reading line, and finely adjusting the lengths of the 9 groups of reading cavities and the filter to control the frequency difference so as to iterate the Q value of the reading cavity, thereby meeting the requirement that the error between the simulation Q value of the reading cavity and the target Q value is within +/-10%. It can be specified that the filter frequencies in the same group are slightly higher than the corresponding read cavity frequencies (within 10 MHz), and the read cavity and filter length data are iterated out and are shown in table 2.

TABLE 2 read Chamber, length of Filter and simulation frequency Table under complete layout

Seventh step: and (5) verifying the complete layout.

As shown in fig. 2, the complete layout of the 9 groups including the qubit, the coupler, the reading cavity, the filter and the reading line is subjected to fine electromagnetic simulation verification, and the simulation verification results are shown in table 2, so that the frequencies and Q values of the reading cavity and the filter in the 9 groups of reading modules can meet the requirements. In addition, the Q value of the quantum bit is 10 ⁸ On the order of magnitude, the designed read module has very little dissipation on the qubit, and the qubit has longer coherence time.

By applying the scheme of the embodiment, the iteration work of the layout design of the reading module for 9-channel multiplexing of one reading line can be completed. Simulation verifies that the frequency and the Q value of the reading cavity and the filter meet the target requirements. Therefore, the embodiment can improve the layout design efficiency of the superconducting quantum chip, optimize the layout, and has instructive significance for the large-scale design, simulation and iteration of the superconducting quantum chip.

Second embodiment

As shown in fig. 7, the present disclosure provides a layout information output apparatus 700 of a read cavity and a filter in a superconducting quantum chip, including:

the obtaining module 701 is configured to obtain target frequency information and target quality factor information of M reading combination devices in a quantum chip, where the M reading combination devices share one reading line to read information of a quantum bit in the quantum chip, and the reading combination devices include a reading cavity and a filter, and M is an integer greater than 1;

a determining module 702, configured to determine first layout information corresponding to each reading combination device based on the target frequency information and the target quality factor information, where the first layout information includes first length information of the reading combination device and first coupling length information between a reading cavity and a filter in the reading combination device;

the first adjusting module 703 is configured to adjust the first length information of each reading combination device based on a first target layout, the target frequency information and the target quality factor information, to obtain second length information of each reading combination device, where the first target layout is a layout of a reading combination device and a reading line, and a coupling length between a reading cavity and a filter in the first target layout is a length indicated by the first coupling length information;

And an output module 704, configured to output second layout information, where the second layout information includes third length information of each reading combination device and first coupling length information between the reading cavity and the filter in each reading combination device, and the third length information is determined based on the second length information.

Optionally, the determining module 702 includes:

a first determining sub-module for determining first length information of each read combining device based on the target frequency information;

the second determining submodule is used for determining second coupling length information between the filter and the reading line in each reading combination device based on a second target layout and a first target quality factor of the filter in the target quality factor information, wherein the second target layout is a layout of the filter and the reading line, and the length of the filter in the second target layout is the length indicated by the length information of the filter in the first length information;

the third determining submodule is used for determining the first coupling length information based on a third target layout and the target quality factor information, wherein the third target layout is a layout of a reading combination device and a reading line, the length corresponding to the reading combination device in the third target layout is the length indicated by the first length information, and the coupling length between the filter and the reading line is the length indicated by the second coupling length information.

Optionally, for each of the first read combining devices, the read device is a read cavity or a filter, the first read combining device is any one of the M read combining devices, and the first determining submodule includes:

the electromagnetic simulation unit is used for carrying out electromagnetic simulation on the reading device to obtain the change relation between the intrinsic frequency and the length information of the reading device;

a first determining unit configured to determine an equivalent dielectric constant of the coplanar waveguide reading device based on the variation relationship;

and a second determining unit configured to determine first initial length information of the reading device based on the equivalent dielectric constant and a target frequency of the reading device in target frequency information of the first reading combination device, the first length information including the first initial length information.

Optionally, the second determining unit is specifically configured to:

Optionally, the second determining submodule is specifically configured to:

Optionally, the third determining submodule is specifically configured to:

Optionally, the first adjusting module 703 includes:

the electromagnetic simulation sub-module is used for carrying out electromagnetic simulation on the reading combination devices based on a first target layout aiming at each reading combination device to obtain a second frequency of a reading cavity and a third frequency of a filter, wherein the second frequency is matched with the length information of the reading cavity in the first length information, and the third frequency is matched with the length information of the filter in the first length information;

the iterative adjustment sub-module is used for iteratively adjusting the first length information based on the second frequency, the third frequency, the target frequency of the reading cavity and the filter of the reading combination device in the target frequency information and the target quality factor information to obtain second length information of the reading combination device;

Optionally, the iterative adjustment submodule includes:

a first iterative adjustment unit, configured to iteratively adjust the first length information based on the second frequency, the third frequency, and a target frequency of a reading cavity and a filter of the reading combination device in the target frequency information, to obtain fourth length information of the reading combination device, where an error between a frequency matched with the length information of the reading cavity in the fourth length information and the target frequency of the reading cavity is less than or equal to the fourth preset threshold, and an error between a frequency matched with the length information of the filter in the fourth length information and the target frequency of the filter is less than or equal to the fifth preset threshold;

The second iteration adjusting unit is used for carrying out iteration adjustment on the fourth length information based on a fourth target layout and the target quality factor information to obtain the second length information, the fourth target layout is the layout of the reading combination device and the reading line, and in the fourth target layout, the coupling length between the reading cavity and the filter is the length indicated by the first coupling length information.

Optionally, the second iterative adjustment unit is specifically configured to:

Optionally, the first relationship includes:

Wherein Γ is _r For the dissipation ratio of the read chamber, κ _f For filter dissipation ratio due to coupling with read line g _rf To read the coupling strength of the cavity and the filter, delta _rf To read the frequency difference of the cavity and the filter, the first relationship further includes: the dissipation ratio of the read chamber is inversely related to the quality factor of the read chamber.

Optionally, the method further comprises:

the electromagnetic simulation module is used for carrying out electromagnetic simulation on the M reading combination devices based on a fifth target layout, so as to obtain first frequency information and first quality factor information of the M reading combination devices, wherein the fifth target layout is a layout of a quantum chip, in the fifth target layout, the coupling length between a reading cavity and a filter is the length indicated by the first coupling length information, and the lengths of the reading cavity and the filter in the reading combination devices are the length indicated by the second length information;

the second adjustment module is configured to iteratively adjust the second length information based on the second target quality factor and the first relationship, to obtain the third length information, when an error between the first frequency information and the target frequency information is greater than a seventh preset threshold, or an error between the first quality factor information and the target quality factor information is greater than an eighth preset threshold;

The layout information output device 700 of the reading cavity and the filter in the superconducting quantum chip provided by the disclosure can realize each process realized by the layout information output method embodiment of the reading cavity and the filter in the superconducting quantum chip, and can achieve the same beneficial effects, and for avoiding repetition, the description is omitted here.

In the technical scheme of the disclosure, the related processes of collecting, storing, using, processing, transmitting, providing, disclosing and the like of the personal information of the user accord with the regulations of related laws and regulations, and the public order colloquial is not violated.

According to embodiments of the present disclosure, the present disclosure also provides an electronic device, a readable storage medium and a computer program product.

FIG. 8 illustrates a schematic block diagram of an example electronic device that may be used to implement embodiments of the present disclosure. Electronic devices are intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular telephones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the disclosure described and/or claimed herein.

As shown in fig. 8, the apparatus 800 includes a computing unit 801 that can perform various appropriate actions and processes according to a computer program stored in a Read Only Memory (ROM) 802 or a computer program loaded from a storage unit 808 into a Random Access Memory (RAM) 803. In the RAM 803, various programs and data required for the operation of the device 800 can also be stored. The computing unit 801, the ROM 802, and the RAM 803 are connected to each other by a bus 804. An input/output (I/O) interface 805 is also connected to the bus 804.

Various components in device 800 are connected to I/O interface 805, including: an input unit 806 such as a keyboard, mouse, etc.; an output unit 807 such as various types of displays, speakers, and the like; a storage unit 808, such as a magnetic disk, optical disk, etc.; and a communication unit 809, such as a network card, modem, wireless communication transceiver, or the like. The communication unit 809 allows the device 800 to exchange information/data with other devices via a computer network such as the internet and/or various telecommunication networks.

The computing unit 801 may be a variety of general and/or special purpose processing components having processing and computing capabilities. Some examples of computing unit 801 include, but are not limited to, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), various specialized Artificial Intelligence (AI) computing chips, various computing units running machine learning model algorithms, a Digital Signal Processor (DSP), and any suitable processor, controller, microcontroller, etc. The calculation unit 801 performs the respective methods and processes described above, for example, a layout information output method of a read cavity and a filter in a superconducting quantum chip. For example, in some embodiments, the layout information outputting method of the read cavity and the filter in the superconducting quantum chip may be implemented as a computer software program tangibly embodied on a machine-readable medium, such as the storage unit 808. In some embodiments, part or all of the computer program may be loaded and/or installed onto device 800 via ROM 802 and/or communication unit 809. When a computer program is loaded into the RAM 803 and executed by the computing unit 801, one or more steps of the layout information output method of the read cavity and filter in the superconducting quantum chip described above may be performed. Alternatively, in other embodiments, the computing unit 801 may be configured to perform the layout information output method of the read cavity and filters in the superconducting quantum chip in any other suitable way (e.g. by means of firmware).

Various implementations of the systems and techniques described here above may be implemented in digital electronic circuitry, integrated circuit systems, field Programmable Gate Arrays (FPGAs), application Specific Integrated Circuits (ASICs), application Specific Standard Products (ASSPs), systems On Chip (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include: implemented in one or more computer programs, the one or more computer programs may be executed and/or interpreted on a programmable system including at least one programmable processor, which may be a special purpose or general-purpose programmable processor, that may receive data and instructions from, and transmit data and instructions to, a storage system, at least one input device, and at least one output device.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program code may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus such that the program code, when executed by the processor or controller, causes the functions/operations specified in the flowchart and/or block diagram to be implemented. The program code may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of this disclosure, a machine-readable medium may be a tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

To provide for interaction with a user, the systems and techniques described here can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to a user; and a keyboard and pointing device (e.g., a mouse or trackball) by which a user can provide input to the computer. Other kinds of devices may also be used to provide for interaction with a user; for example, feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including acoustic input, speech input, or tactile input.

The systems and techniques described here can be implemented in a computing system that includes a background component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front-end component (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such background, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local Area Networks (LANs), wide Area Networks (WANs), and the internet.

The computer system may include a client and a server. The client and server are typically remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server may be a cloud server, a server of a distributed system, or a server incorporating a blockchain.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps recited in the present disclosure may be performed in parallel, sequentially, or in a different order, provided that the desired results of the disclosed aspects are achieved, and are not limited herein.

The above detailed description should not be taken as limiting the scope of the present disclosure. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present disclosure are intended to be included within the scope of the present disclosure.

Claims

1. A layout information output method of a reading cavity and a filter in a superconducting quantum chip comprises the following steps:

outputting second layout information, wherein the second layout information comprises third length information of each reading combination device and first coupling length information between a reading cavity and a filter in each reading combination device, and the third length information is determined based on the second length information;

the adjusting the first length information of each reading combination device based on the first target layout, the target frequency information and the target quality factor information to obtain second length information of each reading combination device includes:

the error between the frequency matched with the length information of the reading cavity in the second length information and the target frequency of the reading cavity is smaller than or equal to a fourth preset threshold value, the error between the frequency matched with the length information of the filter in the second length information and the target frequency of the filter is smaller than or equal to a fifth preset threshold value, and the error between the quality factor of the reading cavity matched with the second length information and the second target quality factor of the reading cavity in the target quality factor information is smaller than or equal to a sixth preset threshold value;

The third length information is determined based on the second length information, including:

determining the second length information as third length information; or,

and carrying out electromagnetic simulation under the layout of the quantum chip, continuing to iteratively adjust the second length information of each reading combination device to obtain third length information of each reading combination device, wherein the coupling length between a reading cavity and a filter in the layout of the quantum chip is the length indicated by the first coupling length information, the matching degree of the frequency information of the reading combination device and the target frequency information under the third length information is larger than that of the reading combination device under the second length information, and the matching degree of the quality factor of the reading cavity and the second target quality factor under the third length information is larger than that of the reading cavity under the second length information.

2. The method according to claim 1, wherein the determining the first layout information corresponding to each read combining device based on the target frequency information and the target quality factor information, respectively, includes:

3. The method of claim 2, wherein the first coupling length information between the read cavity and the filter in the M read combining devices is the same.

4. The method of claim 2, wherein, for each of a first read combining device that is a read cavity or a filter, the first read combining device is any one of the M read combining devices, the determining first length information for each read combining device based on the target frequency information comprises:

5. The method of claim 4, wherein the determining the first initial length information of the reading device based on the equivalent dielectric constant and the target frequency of the reading device in the target frequency information of the first reading combination device comprises:

6. The method according to claim 2, wherein the determining second coupling length information between the filter and the read line in each read combination device based on the second target layout and the first target quality factor of the filter in the target quality factor information comprises:

7. The method of claim 2, wherein the determining the first coupling length information based on a third target layout and the target quality factor information comprises:

8. The method of claim 1, wherein iteratively adjusting the first length information based on the second frequency, the third frequency, a target frequency of a read cavity and a filter of the read combining device in the target frequency information, and the target quality factor information to obtain second length information of the read combining device comprises:

9. The method according to claim 8, wherein iteratively adjusting the fourth length information based on a fourth target layout and the target quality factor information to obtain the second length information includes:

10. The method of claim 9, wherein the first relationship comprises:

wherein Γ is _r For the dissipation ratio of the read chamber, κ _f For filter dissipation ratio due to coupling with read line g _rf To read the coupling strength of the cavity and the filter, delta _rf To read the frequency difference of the cavity and the filter, the first relationship further includes: the dissipation ratio of a read chamber is inversely related to the quality factor of the read chamberIs tied up.

11. The method according to claim 9, further comprising, before the outputting the second layout information:

12. The method of claim 1, wherein the target frequency information is obtained by:

13. A layout information output device of a reading cavity and a filter in a superconducting quantum chip comprises:

the output module is used for outputting second layout information, the second layout information comprises third length information of each reading combination device and first coupling length information between a reading cavity and a filter in each reading combination device, and the third length information is determined based on the second length information;

the first adjustment module includes:

determining the second length information as third length information; or,

14. The apparatus of claim 13, wherein the means for determining comprises:

15. The apparatus of claim 14, wherein the first coupling length information between the read cavity and the filter in the M read combining devices is the same.

16. The apparatus of claim 14, wherein for each of a first read combining device, the read device is a read cavity or a filter, the first read combining device is any one of the M read combining devices, the first determination submodule includes:

17. The apparatus of claim 16, wherein the second determining unit is specifically configured to:

18. The apparatus of claim 14, wherein the second determination submodule is configured to:

19. The apparatus of claim 14, wherein the third determination submodule is configured to:

20. The apparatus of claim 13, wherein the iterative adjustment submodule comprises:

21. The apparatus of claim 20, wherein the second iterative adjustment unit is specifically configured to:

22. The apparatus of claim 21, wherein the first relationship comprises:

23. The apparatus of claim 21, further comprising:

24. The apparatus of claim 13, wherein the target frequency information is obtained by:

25. An electronic device, comprising:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein,,

the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method of any one of claims 1-12.

26. A non-transitory computer readable storage medium storing computer instructions for causing the computer to perform the method of any one of claims 1-12.