CN112444738A - Method for verifying crosstalk residue of superconducting quantum chip - Google Patents
Method for verifying crosstalk residue of superconducting quantum chip Download PDFInfo
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- CN112444738A CN112444738A CN201910804641.5A CN201910804641A CN112444738A CN 112444738 A CN112444738 A CN 112444738A CN 201910804641 A CN201910804641 A CN 201910804641A CN 112444738 A CN112444738 A CN 112444738A
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Abstract
The invention belongs to the field of chip testing, and particularly discloses a crosstalk residue verification method for a superconducting quantum chip, which comprises the following steps of determining a crosstalk compensation matrix based on a crosstalk measurement matrix, wherein the crosstalk compensation matrix comprises the following steps: the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix; determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip; performing operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip; and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance. The invention verifies that the crosstalk residue of the superconducting quantum chip provides support and basis for crosstalk compensation of the superconducting quantum chip.
Description
Technical Field
The invention belongs to the field of chip testing, and particularly relates to a crosstalk residue verification method for a superconducting quantum chip.
Background
The superconducting quantum chip is provided with a plurality of superconducting quantum bit devices, the plurality of superconducting quantum bit devices are all coupled and connected with magnetic flux modulation lines, the working performance of the superconducting quantum bit is influenced not only by the magnetic flux modulation signal provided by the magnetic flux modulation line connected with the superconducting quantum chip, but also by the magnetic flux modulation signal provided by the magnetic flux modulation lines coupled and connected with other superconducting quantum chips on the superconducting quantum chip, namely crosstalk exists between any two superconducting quantum bit devices, and the crosstalk influences the working performance of the superconducting quantum chip.
The crosstalk existing on the superconducting quantum chip is compensated, and the method has great significance for the precise operation of the superconducting quantum chip. At present, no suitable crosstalk compensation method for the superconducting quantum chip exists.
Disclosure of Invention
The invention aims to provide a method for verifying crosstalk residue of a superconducting quantum chip, which aims to overcome the defects in the prior art, can measure the working performance of the superconducting quantum chip based on a crosstalk compensation matrix determined by a crosstalk matrix obtained by measurement, and provides support and basis for crosstalk compensation of the superconducting quantum chip by verifying the crosstalk residue of the superconducting quantum chip.
The technical scheme adopted by the invention is as follows:
a superconducting quantum chip crosstalk residual verification method, the method comprising:
determining a crosstalk compensation matrix based on the crosstalk measurement matrix, wherein: the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix;
determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip;
performing operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip;
and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance.
Furthermore, a plurality of superconducting quantum bit devices are arranged on the superconducting quantum chip; the preset working performance comprises the following steps: presetting the working frequency of a selected superconducting qubit device as a first frequency value, and presetting the working frequency of other superconducting qubit devices as a second frequency value, wherein: the first frequency value and the second frequency value are different;
determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip; the method specifically comprises the following steps:
determining the pulse bias regulation signal amplitude corresponding to each superconducting qubit device based on the selected first frequency value of the superconducting qubit device, the second frequency values of other superconducting qubit devices, and the crosstalk compensation matrix, and recording as a first signal combination.
Further, the preset conditions include: each superconducting qubit device has a corresponding direct-current voltage bias signal when the second frequency value is obtained, and the direct-current voltage bias signal is recorded as a second signal combination;
the performing an operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip specifically includes:
under the condition that the first signal combination and the second signal combination are simultaneously applied to the superconducting qubit, respectively obtaining an operating frequency measurement of the selected superconducting qubit device and operating frequency measurements of other respective superconducting qubit devices.
Further, the obtaining of the operating frequency measurement value of the superconducting qubit device to be measured specifically includes:
aiming at the superconducting qubit device to be measured, performing an energy spectrum experiment based on a corresponding preset frequency value to determine a corresponding frequency initial value;
determining two second qubit modulation decomposition signals with interval delay parameters; the frequency of the second qubit controlled decomposed signal is equal to the initial frequency value of the superconducting qubit device, and the preset oscillation frequency of the second qubit controlled decomposed signal is a fixed value; the amplitude of the second qubit modulation decomposition signal is equal to half of the amplitude of a first qubit modulation decomposition signal required for controlling the quantum state in the superconducting qubit device to undergo a flip change, and the first qubit modulation decomposition signal is determined by means of the frequency initial value;
applying the first signal combination, the second signal combination and two second qubit modulation decomposition signals with interval delay parameters on the superconducting quantum chip;
obtaining a change curve of the superconducting qubit reading feedback signal along with the interval delay parameter between the two second qubit regulation decomposition signals, and recording the change curve as a qubit coherence time curve;
determining an oscillation actual frequency value according to the quantum bit coherence time curve;
and determining the working frequency measurement value according to the initial frequency value, the actual oscillation frequency value and the preset oscillation frequency value.
Further, the determining, by performing an energy spectrum experiment on the superconducting qubit device to be measured based on the corresponding preset frequency value, a corresponding frequency initial value specifically includes:
setting a first qubit regulation and control signal corresponding to the superconducting qubit device to be measured, wherein the first qubit regulation and control signal takes a preset frequency value corresponding to the superconducting qubit device to be measured as a center and has a set frequency range;
applying the first signal combination, the second signal combination, a first qubit modulation signal, and a superconducting qubit read signal on the superconducting quantum chip;
obtaining a variation curve of a qubit feedback reading signal along with a set frequency range of the first qubit regulation signal, and recording the variation curve as a qubit characteristic energy spectrum curve;
and determining a frequency initial value corresponding to the superconducting qubit device to be measured according to the qubit characteristic energy spectrum curve.
Further, the determining the first qubit modulation and decomposition signal by means of the initial frequency value specifically includes:
setting a preset quantum bit regulation signal with an amplitude value parameter; the amplitude value parameter of the preset qubit regulation and control signal is a series of values which are increased in an arithmetic progression in an amplitude range interval A; the frequency of the preset qubit regulation signal is equal to the initial frequency value of the superconducting qubit device;
when the first signal combination, the second signal combination and the preset qubit regulation and control signal are applied, obtaining a change curve of the superconducting qubit reading feedback signal along with the amplitude value parameter of the preset qubit regulation and control signal, and recording the change curve as a Rabi experiment oscillation attenuation curve;
and determining a specific value of an amplitude value parameter of the preset qubit regulation and control signal for realizing quantum state inversion in the qubit device for the first time according to the Rabi experimental oscillation attenuation curve, and recording the specific value as a pi pulse measurement amplitude value.
Further, the determining the first qubit modulation decomposition signal further comprises:
and adjusting the power of the preset qubit regulation and control signal according to the comparison between the pi pulse measurement amplitude value and a preset condition.
Further, the determining the working frequency measurement value according to the initial frequency value, the actual oscillation frequency value, and the preset oscillation frequency value specifically includes:
determining an oscillation frequency offset according to the oscillation actual frequency value and the oscillation preset frequency value, wherein: the oscillation frequency offset is equal to the absolute value of the difference value obtained by subtracting the oscillation preset frequency value from the oscillation actual frequency value;
determining the working frequency measurement value according to the oscillation frequency offset and the frequency initial value, wherein: the measured value of the working frequency is equal to the initial value of the frequency + -the offset of the oscillation frequency.
Further, the determining whether crosstalk residue exists on the superconducting quantum chip by comparing the measured working performance with the preset working performance specifically includes:
and comparing the working frequency measured value of the selected superconducting qubit device with the first frequency value, and comparing the working frequency measured values of other superconducting qubit devices with the second frequency values, and if the two values are equal, judging that no crosstalk residue exists.
Further, the preset working performance further includes:
replacing the selected superconducting qubit device, correspondingly updating a preset frequency value of the selected superconducting qubit device to be a first frequency updating value aiming at the replacement of the selected superconducting qubit device, and updating preset frequency values corresponding to other superconducting qubit devices to be second frequency updating values;
wherein: the first frequency updating value and the first frequency value are both frequency values corresponding to two bit working points of the superconducting qubit device;
and the second frequency updating value and the second frequency value are both frequency values corresponding to the single-bit working point of the superconducting qubit device.
Compared with the prior art, the crosstalk compensation matrix is determined based on the crosstalk measurement matrix, wherein: the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix; determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip; performing operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip; and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance. The invention verifies that the crosstalk residue of the superconducting quantum chip provides support and basis for crosstalk compensation of the superconducting quantum chip.
Drawings
FIG. 1 is a diagram of the internal structure of a superconducting quantum chip according to the present invention;
FIG. 2 is a flow chart of a superconducting quantum chip crosstalk matrix measurement of the present invention;
FIG. 3 is a method of obtaining measured performance of a superconducting quantum chip according to the present invention;
FIG. 4 is a method for obtaining an initial frequency value of a superconducting qubit device by energy spectrum experiments according to the present invention;
FIG. 5 is a method of obtaining a first qubit modulation signal according to the invention;
FIG. 6 is a superconducting qubit characteristic spectrum plot of the present invention;
FIG. 7 is a schematic diagram of the Rabi experimental oscillation attenuation curve of the present invention;
FIG. 8 is a schematic diagram of the coherence time curve of the present invention.
Detailed Description
The embodiments described below with reference to the drawings are illustrative only and should not be construed as limiting the invention.
Embodiment 1 of the present invention provides a method for verifying crosstalk residue of a superconducting quantum chip, as shown in fig. 1, a plurality of superconducting qubits are arranged on the superconducting quantum chip, and each superconducting qubit includes a superconducting qubit detector and a superconducting qubit device that are coupled to each other; one end of the superconducting qubit detector, which is far away from the superconducting qubit device, is connected to a data transmission bus integrally arranged on the superconducting quantum chip, and the data transmission bus is used for receiving superconducting qubit reading signals and transmitting superconducting qubit reading feedback signals; the superconducting qubit device is connected with a first control signal transmission line and a second control signal transmission line, the first control signal provided by the first control signal transmission line comprises a magnetic flux modulation signal, and the second control signal provided by the second control signal transmission line comprises a qubit regulation signal; wherein the magnetic flux modulation signal is used for controlling the change of the working frequency of the superconducting qubit device; the qubit modulation signal is used to control a change in a quantum state of the superconducting qubit device.
The magnetic flux modulation signal comprises a direct current voltage bias signal and/or a pulse bias regulation signal, and the direct current voltage bias signal and the pulse bias regulation signal can regulate and control the frequency of the superconducting qubit device.
Specifically, the magnetic flux modulation signal applied to any one of the superconducting qubit devices through the first control signal transmission line not only generates a coupling effect with the connected superconducting qubit device and controls the frequency of the superconducting qubit device, but also generates mutual inductance coupling with other superconducting qubit devices, so as to influence the regulation and control precision of the magnetic flux modulation signal applied to other superconducting qubit devices on the frequency of the superconducting qubit device, that is, crosstalk between any two superconducting qubits.
Crosstalk between the superconducting qubit devices can directly affect the regulation and control effect of the magnetic flux modulation signal on any one of the superconducting qubit devices on the frequency of the connected superconducting qubit device, so that the frequency of the superconducting qubit device cannot reach a predetermined target value, the overall performance of the superconducting quantum chip is affected, and the control precision of the superconducting quantum chip is affected.
The embodiment provides a crosstalk residue verification method applicable to the above superconducting quantum chip, that is, a crosstalk residue verification method of a superconducting quantum chip, as shown in fig. 2, specifically including:
step S101: determining a crosstalk compensation matrix based on the crosstalk measurement matrix, wherein: the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix;
step S102: determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip;
step S103: performing operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip;
step S104: and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance.
The above process, determining a crosstalk compensation matrix based on the crosstalk measurement matrix, wherein: the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix; then, based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip, determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance; performing operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip; and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance. The matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix, so that the crosstalk on the superconducting quantum chip under the crosstalk verification condition determined by the crosstalk compensation matrix is compensated, and then whether crosstalk residues exist on the superconducting quantum chip is judged by comparing the measurement working performance with the preset working performance.
It is known that when the magnetic flux modulation signal is applied through the first control signal transmission line of any one of the superconducting qubit devices on the superconducting qubit chip, not only the frequency of the connected superconducting qubit device can be regulated, but also crosstalk influence is generated on the frequencies of other superconducting qubit devices, so that a crosstalk measurement matrix of all the superconducting qubit devices of the superconducting qubit chip can be obtained through testing.
It should be noted that the crosstalk matrix measurement of the superconducting qubit chip is to measure the crosstalk influence of the pulse bias control signal applied to each of the superconducting qubit devices on the superconducting qubit chip on other superconducting qubit devices, and is specifically embodied to influence the frequencies of other superconducting qubit devices.
Based on this, the determining the crosstalk compensation matrix based on the crosstalk measurement matrix in step S101 specifically includes:
step S101-1: and testing to obtain a crosstalk measurement matrix.
Specifically, any one of the superconducting qubit devices on the superconducting qubit chip is selected as a target to be measured, and the dc voltage bias signal is applied to the selected superconducting qubit device through the first control signal transmission line so that the frequency of the superconducting qubit device is at the single-bit operating point frequency; applying the pulse bias control signal with a fixed voltage value to any other superconducting qubit device on the superconducting quantum chip through the first control signal transmission line, measuring a superconducting qubit device characteristic energy spectrum curve of the selected superconducting qubit device through an energy spectrum experiment, finding the fixed voltage value and the corresponding frequency of the superconducting qubit device through the superconducting qubit device characteristic energy spectrum curve, and converting the frequency of the superconducting qubit device read through the first qubit device characteristic energy spectrum curve into an equivalent voltage value of the corresponding direct current voltage bias signal through a corresponding relation between the frequency of the superconducting qubit device and the applied direct current voltage bias signal, namely forming the pulse bias control signal applied by the other superconducting qubit devices and the direct current voltage applied to the selected superconducting qubit device The ratio of the equivalent voltage values of the bias signals.
When the fixed voltage value of the pulse bias control signal applied to the other superconducting qubit devices is set to at least 2 values, at least 2 of the ratios can be measured, and at least 2 of the ratios are fitted to obtain a fitting curve, wherein the slope of the fitting curve is recorded as a weight coefficient of a linear relationship between the pulse bias control signal and the equivalent voltage value, that is, a crosstalk coefficient between any two superconducting qubit devices. And testing the crosstalk coefficient between any two superconducting qubit devices on the superconducting quantum chip to obtain a crosstalk test matrix.
Through the described measurement process of the crosstalk test matrix, it can be found that the crosstalk test matrix represents the influence relationship that the frequency of any one superconducting qubit device is influenced by the pulse bias regulation and control signals applied to other superconducting qubit devices.
Step S101-2: setting a crosstalk compensation matrix based on the crosstalk test matrix, wherein: and the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix.
The crosstalk compensation matrix satisfying the condition that the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix can adjust the pulse bias regulation and control signal applied to each superconducting qubit device measured by the crosstalk test matrix to influence the frequency crosstalk of other superconducting qubit devices, and ensure that the magnetic flux modulation signal is applied through the first control signal transmission line of the superconducting qubit device, so that the frequency of the superconducting qubit devices connected to the superconducting quantum chip can reach the frequency of a single-bit working point or the frequency of two-bit working points, and the frequency of other superconducting qubit devices cannot be influenced.
The single-bit working point frequency refers to the frequency of the selected superconducting qubit when the single-bit logic gate operation is performed on the superconducting quantum chip, and when a quantum program or a quantum algorithm is operated when the single-bit working point frequency is selected, the decoherence time of the superconducting qubit is long and the algorithm fidelity is high; the two-bit operating point frequency refers to the frequency of the selected superconducting qubit when the two-bit operation is performed, and particularly, when the two-bit logic gate operation is performed, the frequency of one superconducting qubit is adjusted to one position, so that a mutual superconducting qubit effect can be generated between the position and the other superconducting qubit.
Step S102: and determining the crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip.
Specifically, the preset working performance of the superconducting quantum chip is as follows: and presetting the working frequency of a selected superconducting qubit device as a first frequency value, wherein the working frequency of other superconducting qubit devices is a second frequency value. Wherein the first frequency value is preferably a two-bit operating point frequency; the second frequency value optimizes the single-bit operating point frequency.
After the preset working performance of the crosstalk compensation matrix and the superconducting quantum chip is confirmed, some signals need to be applied to the superconducting quantum chip to enable the superconducting quantum chip to reach the preset working performance, namely, the crosstalk verification condition of the superconducting quantum chip.
Specifically, confirming that the crosstalk verification conditions of the superconducting quantum chip include:
step S102-1: determining the pulse bias regulation signal amplitude corresponding to each superconducting qubit device based on the selected first frequency value of the superconducting qubit device, the second frequency values of other superconducting qubit devices, and the crosstalk compensation matrix, and recording as a first signal combination.
It should be noted that, based on the first frequency value of the selected superconducting qubit device, the second frequency values of the other superconducting qubit devices, and the crosstalk compensation matrix, a process of determining the amplitude of the pulse bias modulation signal corresponding to each superconducting qubit device may be performed based on matrix multiplication, that is, when the crosstalk compensation matrix is multiplied to obtain a crosstalk measurement matrix, the pulse bias modulation signal (marked as an original first signal combination) is applied through the first control signal transmission line of each superconducting qubit device, so as to obtain a first signal combination (marked as an updated first signal combination).
The matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix. And the crosstalk measurement matrix equals the original first signal combination to the first signal combination under the influence of crosstalk; therefore, the first signal combination after crosstalk compensation is updated is equal to the first signal combination without crosstalk influence, and a preset regulation target is conveniently achieved.
In addition, in the implementation of the present invention, it is to be verified that when the frequency of the selected superconducting qubit device is converted from the first frequency value to the second frequency value, the remaining superconducting qubit devices still have the frequency in the first frequency value, by applying the updated pulse bias regulation signal to the first control signal transmission line of the selected superconducting qubit device in combination with the updated pulse bias regulation signal. Therefore, it is necessary to determine the amplitude of the pulse bias modulation signal corresponding to each of the superconducting qubit devices, and to record the amplitude of each of the pulse bias modulation signals as a first signal combination.
Step S102-2: and determining a corresponding direct-current voltage bias signal when each superconducting qubit device has the second frequency value, and recording the direct-current voltage bias signal as a second signal combination, namely a preset condition.
Specifically, the magnetic flux modulation signal applied to the magnetic flux modulation line of each qubit device includes a dc voltage bias signal and/or a pulse bias regulation signal, and both the dc voltage bias signal and the pulse bias regulation signal can regulate and control the frequency of the superconducting qubit device. In this embodiment, the pulse bias control signal needs to be adjusted based on the crosstalk compensation matrix, so that the control effect of the dc voltage bias signal is not affected by crosstalk, and therefore, in this embodiment, the dc voltage bias signal applied to each superconducting qubit device needs to be preset and recorded as a second signal combination, where the second signal combination enables the frequency of the corresponding superconducting qubit device to be at the second frequency value.
Step S103: and measuring the working performance of the superconducting quantum chip based on the determined condition of crosstalk residue verification and a preset condition.
Specifically, as shown in fig. 3, the operating frequency measurement value of the selected superconducting qubit device and the operating frequency measurement values of the other superconducting qubit devices are obtained respectively according to the crosstalk residue verification condition (the updated first signal combination) and the preset condition (the second signal combination) determined in step S102. The method specifically comprises the following steps:
and S103-1, aiming at the superconducting qubit device to be measured, carrying out an energy spectrum experiment based on a corresponding preset frequency value to determine a corresponding frequency initial value.
Specifically, as shown in fig. 4, each superconducting qubit device on the superconducting quantum chip is preset with a corresponding frequency value, and each preset frequency value is used to set a parameter of the qubit modulation signal applied to each superconducting qubit device. And performing an energy spectrum experiment through a frequency value preset by the superconducting qubit device, so as to measure a frequency initial value of the superconducting qubit device. The steps of the energy spectrum experiment comprise:
step S103-1-1: setting a first qubit regulation and control signal corresponding to the superconducting qubit device to be measured, wherein the first qubit regulation and control signal has a set frequency range centered on a preset frequency value corresponding to the superconducting qubit device to be measured.
Specifically, the first qubit adjustment signal is applied via the second control signal transmission line on the superconducting qubit device to change quantum state information in the superconducting qubit device. Therefore, the frequency of the first qubit modulation signal needs to be set near the preset frequency value of the superconducting qubit device. When the energy spectrum test is specifically implemented, the frequency of the first qubit modulation signal is set to be centered on a preset frequency value corresponding to the superconducting qubit device, and the frequency range is set. When the initial frequency value of the superconducting qubit device is tested, the frequency change of the superconducting qubit device is scanned and measured in a set frequency range, so that the measured initial frequency value of the superconducting qubit device is more accurate.
Step S103-1-2: applying the first signal combination, the second signal combination, a first qubit modulation signal, and a superconducting qubit read signal on the superconducting qubit chip.
In particular, the first signal combination, the second signal combination, is applied through the first control signal transmission line of the superconducting qubit device, wherein the first signal combination causes a selected frequency of the superconducting qubit device to be measured at a first frequency value; the second signal combination causes the other of the superconducting qubit device frequencies to be at a second frequency value; and applying the first qubit modulation signal via the second control signal transmission line of the superconducting qubit device. The frequency information and the quantum state information of the superconducting qubit device can be changed by the applied first signal combination, the applied second signal combination and the applied first qubit regulation signal, the frequency information and the quantum state information of the superconducting qubit device are read by the superconducting qubit reading signal applied by the data transmission bus on the superconducting qubit chip are changed, and the frequency information and the quantum state information of the superconducting qubit device are measured by the superconducting qubit reading feedback signal received by the data transmission bus on the superconducting qubit chip.
Step S103-1-3: and obtaining a change curve of the qubit feedback reading signal along with the set frequency range of the first qubit regulation signal, and recording the change curve as a qubit characteristic energy spectrum curve.
Specifically, the qubit feedback read signal is received through the data transmission bus on the superconducting qubit chip, wherein the frequency information of the qubit detector is measured by the superconducting qubit feedback signal; in particular, it is reflected in a change of the dispersion drift value of the frequency of the qubit detector. And the change in the frequency dispersion drift value of the qubit detector is due to a change in the frequency information and/or the quantum state information of the superconducting qubit device. The first qubit modulation signal applied via the second control signal transmission line of the superconducting qubit device has a preset frequency range, and a variation curve of the qubit feedback read signal with the set frequency range of the first qubit modulation signal can be measured, that is, a variation curve of the frequency of the superconducting qubit device with the frequency of the first qubit modulation signal is measured. This step of the experiment may also be referred to as a spectrum experiment measuring the frequency of the superconducting qubit device.
Step S103-1-4: and determining a frequency initial value corresponding to the superconducting qubit device to be measured according to the qubit characteristic energy spectrum curve.
Specifically, as shown in fig. 6, when the two-bit operating point voltage is applied through the first control signal transmission line on the superconducting qubit chip, a variation curve of the superconducting qubit reading feedback signal with the frequency of the qubit modulation signal is measured. When the frequency of the qubit modulation signal is equal to the frequency of the superconducting qubit device, the response effect of the superconducting qubit device is most obvious, and the frequency corresponding to the peak of the signal peak in the characteristic energy spectrum curve of the superconducting qubit device measured at the moment, namely the frequency of the superconducting qubit device, is recorded as the initial frequency value of the superconducting qubit device.
Step S103-2: determining two second qubit modulation decomposition signals with interval delay parameters; the frequency of the second qubit controlled decomposed signal is equal to the initial frequency value of the superconducting qubit device, and the preset oscillation frequency of the second qubit controlled decomposed signal is a fixed value; the amplitude of the second qubit modulation decomposition signal is equal to half of the amplitude of a first qubit modulation decomposition signal required for controlling a quantum state in the superconducting qubit device to undergo a flip change, the first qubit modulation decomposition signal being determined by means of the frequency initial value.
Specifically, the frequency setting of the second qubit modulation decomposition signal is equal to the initial frequency value of the superconducting qubit device; the second qubit modulation decomposition signal has an amplitude equal to half of the amplitude of the first qubit modulation decomposition signal. The frequency of the first qubit modulation decomposition signal is also equal to the initial frequency value of the superconducting qubit device, and the amplitude of the first qubit modulation decomposition signal can enable a quantum state in the superconducting qubit device to be turned by 180 degrees, so that the second qubit modulation decomposition signal can enable the quantum state in the superconducting qubit device to rotate by a displacement distance of 90 degrees along a rotation axis.
Setting the second qubit modulation and decomposition signal into a plurality of Ramsey waveforms according to an interval delay parameter, wherein an oscillation preset frequency of the Ramsey waveforms is set to be a fixed value, that is, the oscillation preset frequency of the second qubit modulation and decomposition signal is a fixed value, the fixed value can be set to be between a difference value between a frequency of the second qubit modulation signal and a frequency of the superconducting qubit device and 6MHz, and the preferred embodiment of the present invention is 2 MHz.
And the second qubit regulation decomposition signal is respectively applied before and after the preset time interval. During specific operation, the second qubit regulation and decomposition signal is applied through the second control signal transmission line firstly, then the application of the second qubit regulation and decomposition signal is stopped, and the second qubit regulation and decomposition signal is applied through the second control signal transmission line for the second time after a preset time interval.
As shown in fig. 5, in the implementation of the present invention, since the frequency setting of the second qubit modulation decomposition signal is equal to the frequency value of the first qubit modulation decomposition signal; the amplitude of the second qubit controlled decomposed signal is equal to half of the amplitude of the first qubit controlled decomposed signal, and when the working performance of the superconducting quantum chip is measured, the first qubit controlled decomposed signal needs to be determined first, and the specific method comprises the following steps:
step S103-2-1: setting a preset quantum bit regulation signal with an amplitude value parameter; the amplitude value parameter of the preset qubit regulation and control signal is a series of values which are increased in an arithmetic progression in an amplitude range interval A; the frequency of the preset qubit regulation signal is equal to the initial frequency value of the superconducting qubit device.
Specifically, in the embodiment of the present invention, the frequency of the qubit modulation signal is always set to the initial frequency value of the superconducting qubit device, so that the modulation effect of the qubit modulation signal on the quantum state of the superconducting qubit device can be maximized; the power of the qubit modulation signal is always set to the first power, and the value of the first power determines the amplitude value of the preset qubit modulation signal. And setting the preset qubit regulation and control signal in an arithmetic progression increasing mode in an amplitude interval A according to the amplitude coefficient.
Wherein the amplitude interval A is defined as 0-1; it should be noted that 0-1 is actually defined as the value normalization, and 0 corresponds to the minimum value that the amplitude can be set; 1 corresponds to the maximum value to which the amplitude can be set. The amplitude coefficients are set in an arithmetic progression mode according to a stepping value of 0.01, and 100 preset qubit regulation sub-signals with fixed amplitude coefficients can be obtained.
Step S103-2-2: and when the first signal combination, the second signal combination and the preset qubit regulation and control signal are applied, obtaining a change curve of the superconducting qubit reading feedback signal along with the amplitude value parameter of the preset qubit regulation and control signal, and recording the change curve as a Rabi experimental oscillation attenuation curve.
Specifically, the first signal combination and the second signal combination are applied through the first control signal transmission line of the superconducting qubit device, the preset qubit regulation and control signal is applied through the second control signal transmission line of the superconducting qubit device, the superconducting qubit reading feedback signal is applied through the data transmission bus of the superconducting quantum chip, the corresponding superconducting qubit reading feedback signal is measured through the data transmission bus on the superconducting quantum chip, respectively, a variation curve of the superconducting qubit reading feedback signal along with an amplitude coefficient of the preset qubit regulation and control signal is obtained, and the variation curve is recorded as a Rabi experimental oscillation attenuation curve. This step may also be referred to as the Rabi experiment.
Step S103-2-3: and determining a specific value of an amplitude value parameter of the preset qubit regulation and control signal for realizing the quantum state inversion in the superconducting qubit device for the first time according to the Rabi experimental oscillation attenuation curve, and recording the specific value as a pi pulse measurement amplitude value.
Specifically, as shown in fig. 7, the amplitude coefficient of the preset qubit modulation sub-signal corresponding to the first half-cycle of the oscillation waveform is read through the Rabi experimental oscillation attenuation curve, and the amplitude coefficient needs to be determined, so as to find the preset qubit modulation sub-signal, i.e., the first qubit modulation decomposition signal, which can realize 180 quantum state inversion in the superconducting qubit device. It should be noted that Rabi experimental oscillation attenuation curve is an oscillation curve having an oscillation period, and the first half period is half of the first oscillation period.
Step S103-2-4: and adjusting the power of the preset qubit regulation and control signal according to the comparison between the pi pulse measurement amplitude value and a preset condition.
Specifically, when the amplitude coefficient of the preset qubit adjustment and control signal corresponding to the first half cycle of the oscillation waveform is read out through the Rabi experimental oscillation attenuation curve, the amplitude coefficient needs to be compared with a preset condition. The power of the preset qubit regulation signal can be adjusted, so that the read amplitude coefficient corresponding to the first half cycle of the oscillation waveform reaches a preset condition.
Wherein, adjusting the power of the preset qubit regulation signal to make the read amplitude coefficient corresponding to the first half cycle of the oscillating waveform reach a preset condition specifically includes:
a: if the amplitude coefficient is located in the first gradient of the amplitude range interval A, the power of the preset qubit regulation signal is increased;
b: if the amplitude coefficient is located in the second gradient of the amplitude range interval A, no operation is performed;
c: and if the amplitude coefficient is located in a third gradient of the amplitude range interval A, reducing the power of the preset qubit regulation signal.
In particular, the first gradient is defined as 0.95- + ∞ofthe amplitude range interval A; the second gradient is defined as 0.7-0.95 of the amplitude range interval A; the third gradient is defined as-infinity-0.7 for the amplitude range interval A.
In a specific implementation of the present invention, the amplitude coefficient of the preset condition is defined as a second gradient of the amplitude range interval a. And when the obtained amplitude coefficient of the qubit modulation sub-signal is in the second gradient, defining the qubit modulation sub-signal corresponding to the amplitude coefficient as the first qubit modulation decomposition signal.
And when the amplitude coefficient of the obtained qubit modulation sub-signal is in the first gradient, increasing the power of the preset qubit modulation signal, and then repeating the step S103-2 until the obtained amplitude coefficient of the qubit modulation sub-signal reaches a second gradient of the preset amplitude range A. And defining the qubit modulation sub-signal corresponding to the amplitude coefficient as the first qubit modulation decomposition signal.
And when the amplitude coefficient of the obtained qubit modulation sub-signal is in the third gradient, reducing the power of the preset qubit modulation signal, and then repeating the step S103-2 until the obtained amplitude coefficient of the qubit modulation sub-signal reaches a second gradient of the preset amplitude range A. And defining the qubit modulation sub-signal corresponding to the amplitude coefficient as the first qubit modulation decomposed signal.
Step S103-3: and applying the first signal combination, the second signal combination and two second qubit regulation decomposition signals with interval delay parameters on the superconducting quantum chip.
Specifically, the second qubit controlled decomposed signal having an amplitude value half of the amplitude parameter of the first qubit controlled decomposed signal is obtained from the first qubit controlled decomposed signal obtained through the Rabi experiment in the step S103-2.
Applying the first signal combination and the second signal combination to the superconducting qubit device via the first control signal transmission line, such that the superconducting qubit device to be measured operates at a two-bit operating point and other superconducting qubit devices operate at a single-bit operating point; and then applying the second qubit regulation and decomposition signal to the superconducting qubit device through a second control signal transmission line of the superconducting qubit device, then stopping applying the second qubit regulation and decomposition signal, after a preset time interval, applying the second qubit regulation and decomposition signal through the second control signal transmission line for a second time, applying the superconducting qubit reading signal through the data transmission bus, receiving the superconducting qubit reading feedback signal from the data transmission bus, and analyzing information related to a quantum state in the superconducting qubit device through the superconducting qubit reading feedback signal. This step of the experiment may also be referred to as a Ramsey experiment.
Step S103-4: obtaining a change curve of the superconducting qubit reading feedback signal along with the interval delay parameter between the two second qubit regulation decomposition signals, and recording the change curve as a qubit coherence time curve;
specifically, the superconducting qubit reading feedback signal is received from the data transmission bus, and the information related to the quantum state in the superconducting qubit device is analyzed through the superconducting qubit reading feedback signal. Wherein the qubit coherence time curve is shown in fig. 8. Each dot in fig. 8 represents a datum, i.e., information of quantum state in the superconducting qubit device measured by the superconducting qubit read feedback signal for each predetermined time interval.
And S103-5, determining an oscillation actual frequency value according to the quantum bit coherence time curve.
Specifically, the qubit coherence time curve is a curve obtained by fitting all the data measured in step S103-4 with a formula, where the formula is as follows:
y＝A+B*exp(-t/T2*)*cos(2*pi*f*t)
wherein, T2*Namely, the coherence time of the superconducting qubit, f, which is the actual frequency value of the oscillation, is measured through the Ramsey experiment. From the plurality of data obtained by measurement, the value of f can be calculated by a formula.
Step S103-6: and determining the working frequency measurement value according to the initial frequency value, the actual oscillation frequency value and the preset oscillation frequency value.
Specifically, the variation of the oscillation frequency can be analyzed by comparing the actual oscillation frequency value measured by the qubit coherence time curve with a preset oscillation frequency value. The variation of the oscillation frequency represents a variation of a frequency of the second qubit modulation decomposition signal, that is, a variation of a frequency of the superconducting qubit device can also be represented.
The initial frequency value of each superconducting qubit device can be directly obtained through an energy spectrum curve of the superconducting qubit device frequency; the oscillation actual frequency value can be calculated through the qubit coherence time curve. And when the Ramsey waveform decomposition is carried out on the second qubit modulation decomposition signal, the preset oscillation frequency value is already set to be a fixed value of 2MHz, so that the working frequency measured value of the superconducting qubit device can be calculated.
Step S103-6-1: determining an oscillation frequency offset according to the oscillation actual frequency value and the oscillation preset frequency value, wherein: the oscillation frequency offset is equal to the absolute value of the difference value of the oscillation actual frequency value minus the oscillation preset frequency value.
Specifically, the frequency of the selected superconducting qubit device may change due to the influence of interference from other superconducting qubit devices, environmental interference, and the like, and thus the oscillation actual frequency value calculated from the Ramsey experimental result may also deviate from a preset oscillation frequency value. Wherein:
and the oscillation frequency offset is the oscillation actual frequency value-the oscillation preset frequency value.
Step S103-6-2: determining the working frequency measurement value according to the oscillation frequency offset and the frequency initial value, wherein: the measured value of the working frequency is equal to the initial value of the frequency + -the offset of the oscillation frequency.
Specifically, the offset of the oscillation frequency represents an offset of the oscillation frequency of the second qubit controlled decomposition signal, that is, an offset of the frequency of the superconducting qubit device can also be represented. The operating frequency measurement value of the superconducting qubit device may be further calculated by the step S103-6-1, where the oscillation frequency offset is the oscillation actual frequency value and the oscillation preset frequency value.
Namely, the measured value of the working frequency is equal to the initial value of the frequency +/-the offset of the oscillation frequency.
In the specific implementation of the invention, the oscillation actual frequency value is measured as fz' through the Rabi experimental oscillation attenuation curve, and the oscillation preset frequency value is set to be fz equal to 2 MHz; the initial value of the frequency of the superconducting qubit device is measured as fq1 through a frequency spectrum experiment of the superconducting qubit device, and then the calculation formula of the measured value of the working frequency is as follows:
fz'-fz＝fq1'-fq
wherein fq1' is the calculated operating frequency measurement of the superconducting qubit device.
Step S104: and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance.
Specifically, the operating frequency measurement value of the superconducting qubit device calculated in the step S103-6-2 is compared with the predetermined frequency of the superconducting qubit device. Comparing the operating frequency measurement to the first frequency value for the superconducting qubit device being measured; comparing the operating frequency measurement to the second frequency value for the other of the superconducting qubit devices.
When the measured operating frequency of the measured superconducting qubit device is equal to the first frequency value and the measured operating frequency of the other superconducting qubit devices is equal to the second frequency value, it may be determined that the crosstalk residue is not present on the superconducting qubit chip.
When the working frequency measurement value of any one of the superconducting qubit devices is judged to be different from the preset frequency value, it can be judged that the crosstalk residue still exists on the superconducting quantum chip, a crosstalk matrix measurement method needs to be introduced based on the obtained measurement working performance, namely the working frequency measurement value of the superconducting qubit device, a more accurate crosstalk matrix is recalculated, and then the recalculated more accurate crosstalk matrix is utilized to repeatedly execute the steps S101-S104 of the invention, perform secondary verification of the crosstalk residue, and continue to compensate and measure and judge the crosstalk residue on the superconducting quantum chip.
In summary, the present embodiment determines the crosstalk compensation matrix based on the crosstalk measurement matrix, where: the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix; determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip; performing operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip; and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance. The invention verifies that the crosstalk residue of the superconducting quantum chip provides support and basis for crosstalk compensation of the superconducting quantum chip.
Example 2
The embodiment 2 of the invention provides a crosstalk residue verification method of a superconducting quantum chip. Embodiment 1 describes performing crosstalk residue verification for selected ones of the superconducting qubit devices on the superconducting quantum chip.
Crosstalk residue verification is required for any superconducting qubit device on the superconducting quantum chip, and it is ensured that the crosstalk compensation matrix and the pulse bias regulation and control signal applied to any superconducting qubit device do not generate crosstalk influence on the frequencies of other superconducting qubit devices.
Specifically, when crosstalk residue verification is performed on the replaced and selected superconducting qubit device, the pulse bias control signal applied to the first control signal transmission line of the replaced and selected superconducting qubit device needs to be adjusted so that a preset frequency value of the pulse bias control signal becomes a first frequency update value, and a first signal update combination is obtained; and simultaneously adjusting the pulse bias regulation and control signals applied to other superconducting qubit devices to enable the preset frequency values corresponding to other superconducting qubit devices to be second frequency updating values, so as to obtain a second signal updating combination.
Wherein: the first frequency updating value and the first frequency value are both frequency values corresponding to two bit working points of the superconducting qubit device; and the second frequency updating value and the second frequency value are both frequency values corresponding to the single-bit working point of the superconducting qubit device.
Repeating the operation of embodiment 1 by using the first signal updating combination and the second signal updating combination, measuring the crosstalk residue of the superconducting qubit device after replacement, and judging. For any of the superconducting qubit devices on the superconducting quantum chip, the first signal update combination and the second signal update combination need to be updated in sequence, and the steps of embodiment 1 are repeated to perform crosstalk residue verification.
During the performance test of the superconducting quantum chip, a crosstalk compensation matrix is calculated based on a measured specific value of a crosstalk matrix of the superconducting quantum chip, namely the crosstalk measurement matrix, the magnetic flux modulation signal applied through the first control signal transmission line on the superconducting quantum chip is calculated based on the crosstalk compensation matrix and is recorded as an update signal, and when the update signal and a direct current voltage bias signal (namely a second signal combination) act, the update signal regulates, controls and cancels the frequency of the superconducting quantum bit device which is not connected with each other so as to perform proper crosstalk compensation operation, so that the regulation and control of the frequency of the superconducting quantum bit device reach a regulation and control expected value of the direct current voltage bias signal. Effectively compensating the crosstalk on the superconducting quantum chip, so that the working performance of the superconducting quantum chip is optimal.
The construction, features and functions of the present invention are described in detail in the embodiments illustrated in the drawings, which are only preferred embodiments of the present invention, but the present invention is not limited by the drawings, and all equivalent embodiments modified or changed according to the idea of the present invention should fall within the protection scope of the present invention without departing from the spirit of the present invention covered by the description and the drawings.
Claims (10)
1. A method for verifying crosstalk residues of a superconducting quantum chip is characterized by comprising the following steps:
determining a crosstalk compensation matrix based on the crosstalk measurement matrix, wherein: the matrix product of the crosstalk compensation matrix and the crosstalk measurement matrix is an identity matrix;
determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip;
performing operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip;
and judging whether crosstalk residues exist on the superconducting quantum chip or not by comparing the measured working performance with the preset working performance.
2. The method of claim 1, wherein a plurality of superconducting qubit devices are disposed on the superconducting quantum chip; the preset working performance comprises the following steps: presetting the working frequency of a selected superconducting qubit device as a first frequency value, and presetting the working frequency of other superconducting qubit devices as a second frequency value, wherein: the first frequency value and the second frequency value are different;
determining a crosstalk verification condition of the superconducting quantum chip corresponding to the preset working performance based on the crosstalk compensation matrix and the preset working performance of the superconducting quantum chip; the method specifically comprises the following steps:
determining the pulse bias regulation signal amplitude corresponding to each superconducting qubit device based on the selected first frequency value of the superconducting qubit device, the second frequency values of other superconducting qubit devices, and the crosstalk compensation matrix, and recording as a first signal combination.
3. The method of claim 2, wherein the preset conditions comprise: each superconducting qubit device has a corresponding direct-current voltage bias signal when the second frequency value is obtained, and the direct-current voltage bias signal is recorded as a second signal combination;
the performing an operation on the superconducting quantum chip based on a preset condition and the crosstalk verification condition to obtain the measurement working performance of the superconducting quantum chip specifically includes:
under the condition that the first signal combination and the second signal combination are simultaneously applied to the superconducting qubit, respectively obtaining an operating frequency measurement of the selected superconducting qubit device and operating frequency measurements of other respective superconducting qubit devices.
4. The method for verifying crosstalk residues of a superconducting quantum chip according to claim 3, wherein the obtaining of the operating frequency measurement value of the superconducting qubit device to be measured specifically comprises:
aiming at the superconducting qubit device to be measured, performing an energy spectrum experiment based on a corresponding preset frequency value to determine a corresponding frequency initial value;
determining two second qubit modulation decomposition signals with interval delay parameters; the frequency of the second qubit controlled decomposed signal is equal to the initial frequency value of the superconducting qubit device, and the preset oscillation frequency of the second qubit controlled decomposed signal is a fixed value; the amplitude of the second qubit modulation decomposition signal is equal to half of the amplitude of a first qubit modulation decomposition signal required for controlling the quantum state in the superconducting qubit device to undergo a flip change, and the first qubit modulation decomposition signal is determined by means of the frequency initial value;
applying the first signal combination, the second signal combination and two second qubit modulation decomposition signals with interval delay parameters on the superconducting quantum chip;
obtaining a change curve of the superconducting qubit reading feedback signal along with the interval delay parameter between the two second qubit regulation decomposition signals, and recording the change curve as a qubit coherence time curve;
determining an oscillation actual frequency value according to the quantum bit coherence time curve;
and determining the working frequency measurement value according to the initial frequency value, the actual oscillation frequency value and the preset oscillation frequency value.
5. The method for verifying crosstalk residue of a superconducting quantum chip according to claim 4, wherein the determining, by performing an energy spectrum experiment on the superconducting qubit device to be measured based on the corresponding preset frequency value, a corresponding initial frequency value specifically comprises:
setting a first qubit regulation and control signal corresponding to the superconducting qubit device to be measured, wherein the first qubit regulation and control signal takes a preset frequency value corresponding to the superconducting qubit device to be measured as a center and has a set frequency range;
applying the first signal combination, the second signal combination, a first qubit modulation signal, and a superconducting qubit read signal on the superconducting quantum chip;
obtaining a variation curve of a qubit feedback reading signal along with a set frequency range of the first qubit regulation signal, and recording the variation curve as a qubit characteristic energy spectrum curve;
and determining a frequency initial value corresponding to the superconducting qubit device to be measured according to the qubit characteristic energy spectrum curve.
6. The method for verifying crosstalk residues of a superconducting quantum chip according to claim 4, wherein the determining the first qubit modulation and decomposition signal by means of the initial frequency value specifically comprises:
setting a preset quantum bit regulation signal with an amplitude value parameter; the amplitude value parameter of the preset qubit regulation and control signal is a series of values which are increased in an arithmetic progression in an amplitude range interval A; the frequency of the preset qubit regulation signal is equal to the initial frequency value of the superconducting qubit device;
when the first signal combination, the second signal combination and the preset qubit regulation and control signal are applied, obtaining a change curve of the superconducting qubit reading feedback signal along with the amplitude value parameter of the preset qubit regulation and control signal, and recording the change curve as a Rabi experiment oscillation attenuation curve;
and determining a specific value of an amplitude value parameter of the preset qubit regulation and control signal for realizing quantum state inversion in the qubit device for the first time according to the Rabi experimental oscillation attenuation curve, and recording the specific value as a pi pulse measurement amplitude value.
7. The qubit operating parameter detection method of claim 6, wherein said determining a first qubit modulation decomposition signal further comprises:
and adjusting the power of the preset qubit regulation and control signal according to the comparison between the pi pulse measurement amplitude value and a preset condition.
8. The method for verifying crosstalk residue of a superconducting quantum chip according to claim 4, wherein the determining the operating frequency measurement value according to the initial frequency value, the actual oscillation frequency value, and the preset oscillation frequency value specifically comprises:
determining an oscillation frequency offset according to the oscillation actual frequency value and the oscillation preset frequency value, wherein: the oscillation frequency offset is equal to the absolute value of the difference value obtained by subtracting the oscillation preset frequency value from the oscillation actual frequency value;
determining the working frequency measurement value according to the oscillation frequency offset and the frequency initial value, wherein: the measured value of the working frequency is equal to the initial value of the frequency + -the offset of the oscillation frequency.
9. The method for verifying crosstalk residues of a superconducting quantum chip according to claim 3, wherein the step of determining whether crosstalk residues exist on the superconducting quantum chip by comparing the measured working performance with the preset working performance specifically comprises:
and comparing the working frequency measured value of the selected superconducting qubit device with the first frequency value, and comparing the working frequency measured values of other superconducting qubit devices with the second frequency values, and if the two values are equal, judging that no crosstalk residue exists.
10. The method of claim 3, wherein the pre-set operating performance further comprises:
replacing the selected superconducting qubit device, correspondingly updating a preset frequency value of the selected superconducting qubit device to be a first frequency updating value aiming at the replacement of the selected superconducting qubit device, and updating preset frequency values corresponding to other superconducting qubit devices to be second frequency updating values;
wherein: the first frequency updating value and the first frequency value are both frequency values corresponding to two bit working points of the superconducting qubit device;
and the second frequency updating value and the second frequency value are both frequency values corresponding to the single-bit working point of the superconducting qubit device.
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