Quantum voltage output method and apparatus based on josephson junction array
By performing zero-step and positive/negative step scans on the Josephson array, accurate IV characteristic curves were obtained, and quantum voltage control parameters were calculated. This solved the problem of inaccurate quantum voltage output and achieved higher precision and more stable quantum voltage signal control.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- STATE GRID JIANGSU ELECTRIC POWER CO LTD MARKETING SERVICE CENT
- Filing Date
- 2025-11-10
- Publication Date
- 2026-05-21
Smart Images
Figure CN2025133705_21052026_PF_FP_ABST
Abstract
Description
A quantum voltage output control method and device based on Josephson array
[0001] This application claims priority to Chinese Patent Application No. 202411645768.4, filed with the Chinese Patent Office on November 18, 2024, the entire contents of which are incorporated herein by reference. Technical Field
[0002] This application relates to the field of metrology, for example to a quantum voltage output control method and device based on Josephson array. Background Technology
[0003] Josephson junctions are superconducting quantum devices based on the Josephson effect, and they have important applications in the field of superconducting electronics. These devices are formed by integrating several to tens of thousands of Josephson junctions on a single chip, creating an array of Josephson junctions. Under specific microwave radiation conditions, these arrays can generate stable voltage signals under the influence of a DC bias current.
[0004] Due to their extremely high voltage stability and accuracy, Josephson junction arrays have become a key technical component for constructing quantum voltage standards. For example, patent CN110095639A discloses an AC quantum voltage generation device, including a host computer, a clock, a drive circuit, a digital voltmeter, a microwave source, a cryogenic probe, a cryogenic Dewar, and a programmable Josephson Voltage Standard (PJVS) array. Specifically: the host computer is connected to the clock, drive circuit, digital voltmeter (DVM), and microwave source, and controls the drive circuit to generate a drive current; the digital voltmeter is connected to the host computer and the cryogenic probe, receiving instructions from the host computer to read the voltage value during the intensity-voltage (IV) characteristic scan of the PJVS array, and then sending the read voltage value to the host computer for storage and analysis; the microwave source is connected to the host computer and the cryogenic probe, generating a microwave signal under the control of the host computer, and outputting the microwave signal onto the PJVS array through the cryogenic probe to excite the PJVS array. The PJVS array generates quantum voltage. A clock is connected to the host computer, drive circuit, digital voltmeter, and microwave source, providing a working clock for these components. A cryogenic probe is connected to the drive circuit, digital voltmeter, microwave source, and PJVS array. The cryogenic probe receives switching control signals generated by the drive circuit, controlling the switching within its internal circuit. The cryogenic probe also receives drive current generated by the drive circuit and outputs it to the PJVS array, driving it to generate the corresponding voltage value. A cryogenic Dewar provides a low temperature for the PJVS array, keeping the PJVS chip in a superconducting state. The accuracy of the IV characteristic scan directly affects the accuracy of the quantum voltage output. Summary of the Invention
[0005] This application provides a quantum voltage output control method and device based on Josephson array, which can improve the accuracy of quantum voltage output.
[0006] A quantum voltage output control method based on a Josephson array, applied to a quantum voltage synthesis system based on a Josephson array, the method comprising:
[0007] Receive array scanning control signals;
[0008] The quantum voltage synthesis system is controlled to perform a zero-step scan according to the array scanning control signal to obtain the zero-step boundary;
[0009] Based on the zero-step boundary, the quantum voltage synthesis system is controlled to perform positive and negative step scanning to obtain positive and negative step IV characteristic curves.
[0010] Receive quantum voltage output request signal;
[0011] Calculate the quantum voltage control parameters based on the quantum voltage output request signal and the positive and negative step IV characteristic curves;
[0012] The quantum voltage synthesis system is controlled to output a quantum voltage signal according to the quantum voltage control parameters.
[0013] A quantum voltage output control device based on a Josephson array using the above method includes:
[0014] The signal receiving module is configured to receive array scanning control signals;
[0015] The zero-step scanning control module is configured to control the quantum voltage synthesis system to perform a zero-step scan according to the array scanning control signal, so as to obtain the zero-step boundary.
[0016] The positive and negative step scanning control module is configured to control the quantum voltage synthesis system to perform positive and negative step scanning based on the zero step boundary, so as to obtain the positive and negative step IV characteristic curves.
[0017] The request module is configured to receive quantum voltage output request signals;
[0018] The control parameter calculation module is configured to calculate the quantum voltage control parameters based on the quantum voltage output request signal and the positive and negative step IV characteristic curves.
[0019] The signal output control module is configured to control the quantum voltage synthesis system to output a quantum voltage signal according to the quantum voltage control parameters. Attached Figure Description
[0020] Figure 1 is a flowchart of an embodiment of the quantum voltage output control method based on Josephson array provided in this application.
[0021] Figure 2 is a schematic diagram of the structure of a quantum voltage synthesis system in the quantum voltage output control method based on Josephson array provided in this application.
[0022] Figure 3 is a flowchart of one embodiment of the zero-step scanning method in the quantum voltage output control method based on Josephson array provided in this application.
[0023] Figure 4 is a schematic diagram of one embodiment of the step in the quantum voltage output control method based on Josephson array provided in this application.
[0024] Figure 5 is a flowchart of an embodiment of positive and negative step scanning in the quantum voltage output control method based on Josephson array provided in this application.
[0025] Figure 6 is a schematic diagram of one embodiment of the positive and negative step IV characteristic curves in the quantum voltage output control method based on Josephson array provided in this application.
[0026] Figure 7 is a flowchart of an embodiment of the quantum voltage control parameter calculation in the quantum voltage output control method based on Josephson array provided in this application.
[0027] Figure 8 is a flowchart of one embodiment of the quantum voltage output control device based on Josephson array provided in this application. Detailed Implementation
[0028] Referring to Figure 1, in some embodiments, a quantum voltage output control method based on a Josephson array is provided, applied to a quantum voltage synthesis system based on a Josephson array, the method comprising:
[0029] S1, Receive array scanning control signal;
[0030] S2. Control the quantum voltage synthesis system to perform a zero-step scan according to the array scanning control signal to obtain the zero-step boundary;
[0031] S3. Based on the zero-step boundary, control the quantum voltage synthesis system to perform positive and negative step scanning to obtain positive and negative step IV characteristic curves;
[0032] S4. Receive quantum voltage output request signal;
[0033] S5. Calculate the quantum voltage control parameters based on the quantum voltage output request signal and the positive and negative step IV characteristic curves;
[0034] S6. Control the quantum voltage synthesis system to output a quantum voltage signal according to the quantum voltage control parameters.
[0035] Referring to Figure 2, the quantum voltage synthesis system includes a bias system 1, a cryogenic system 2, a microwave source 3, and a Josephson array 4, which includes multiple array elements 41.
[0036] Among them, the cryogenic system 2 provides a cryogenic environment for the Josephson array 4, the bias system 1 provides a bias current for driving the Josephson array 4, and the microwave source 3 provides the required microwave frequency for the Josephson array 4.
[0037] For example, in step S1, the execution subject of the method provided in this embodiment can be an industrial control computer that receives the array scanning control signal input by the user.
[0038] Referring to Figure 3, in step S2, the quantum voltage synthesis system is controlled to perform a zero-step scan according to the array scanning control signal to obtain the zero-step boundary, including:
[0039] S21. Control the output power of the microwave source to the minimum, and set the first bias current scan step size;
[0040] S22. Starting from 0, control the bias system to sequentially increase the output bias current and apply it to the array unit according to the first bias current scanning step size. Detect the output voltage of the array unit under each bias current and calculate the output voltage change. Stop scanning when the output voltage change exceeds a preset threshold.
[0041] S23. Determine whether the corresponding array unit loses its superconducting properties based on the first curve of the output voltage changing with the bias current.
[0042] S24. If the array unit does not lose its superconducting properties, determine the zero-step boundary based on the first change curve.
[0043] For example, in step S21, the output power of the microwave source 3 is controlled to be at its lowest, for example -20dBm, and the first bias current scan step size can be 1mA-2mA.
[0044] In step S22, starting from 0, the control bias system sequentially increases the output bias current and applies it to the array unit according to the first bias current scan step size. Under each bias current, the output voltage of the array unit is detected and the output voltage change is calculated. This output voltage change is the difference between the output voltage under the current bias current and the output voltage under the previous bias current. The scan stops when the output voltage change exceeds a preset threshold.
[0045] In step S23, after stopping the scan, the first curve of the output voltage changing with the bias current is obtained and it is determined whether the corresponding array unit has lost its superconducting characteristics. For example, if a step appears in the first curve of the output voltage changing with the bias current, it is determined that the corresponding array unit has not lost its superconducting characteristics. Conversely, if no step appears in the first curve, it indicates that the array unit in that segment has experienced a frozen flux phenomenon and lost its superconducting characteristics.
[0046] Referring to Figure 4, the step is defined as follows: within a certain bias current range, the output voltage remains constant, and at both ends of the bias current range, the corresponding output voltage jumps. In Figure 4, the output voltage V remains constant between the bias currents I0 and I1, and the output voltage V jumps at bias currents I0 and I1, which constitutes the step.
[0047] In step S24, if the array unit does not lose its superconducting properties, that is, if a step appears in the first change curve, then the zero step boundary can be determined as the bias current corresponding to the starting point of the first step in the first change curve.
[0048] Referring to Figure 5, in step S3, based on the zero-step boundary, the quantum voltage synthesis system is controlled to perform positive and negative step scanning to obtain positive and negative step IV characteristic curves, including:
[0049] S31. Control the output power of the microwave source to a preset value, and set the second bias current scanning step size, the third bias current scanning step size and the fourth bias current scanning step size, wherein the second bias current scanning step size is greater than the third bias current scanning step size.
[0050] S32. Using the zero-step boundary as the first scanning starting point, control the bias system to sequentially increase the output bias current and apply it to the array unit according to the second bias current scanning step size. Detect the output voltage of the array unit under each bias current to obtain a second variation curve of the output voltage with the bias current, and obtain the second scanning starting point based on the second variation curve.
[0051] S33. Starting from the second scanning start point, control the bias system to increase the output bias current sequentially according to the third bias current scanning step size and apply it to the array unit. Detect the output voltage of the array unit under each bias current to obtain the third variation curve of the output voltage with the bias current, and obtain a preset number of first current points to be calculated based on the third variation curve.
[0052] S34. Starting from the second scanning start point, control the bias system to sequentially decrease the output bias current and apply it to the array unit according to the third bias current scanning step size. Detect the output voltage of the array unit under each bias current to obtain a fourth variation curve of the output voltage as a function of the bias current. Obtain a preset number of second current points to be calculated based on the fourth variation curve.
[0053] S35. Calculate the average value of the second scanning starting point, the preset number of the first current points to be calculated and the second current points to be calculated, and use the average value as the left boundary of the positive step.
[0054] S36. Taking the left boundary of the positive step as the third scanning starting point, the bias system is controlled to increase the output bias current sequentially according to the fourth bias current scanning step and apply it to the array unit. The output voltage of the array unit is detected under each bias current and the output voltage change is calculated. When the output voltage change exceeds a preset threshold, the scanning is stopped to obtain the fifth change curve of the output voltage with the bias current. The positive step boundary and the positive step width are obtained according to the fifth change curve.
[0055] S37. Based on the principle of symmetry, the right boundary, negative boundary, and negative width of the negative step are obtained according to the left boundary, positive step boundary, and positive step width of the positive step.
[0056] S38. Obtain the positive and negative step IV characteristic curves of the corresponding array element based on the left boundary, positive step boundary, positive step width, right boundary, negative step boundary, and negative step width of the positive step.
[0057] For example, in step S31, the output power of the microwave source is controlled to a preset value, such as between 0 dBm and 6 dBm.
[0058] In step S32, starting from the zero-step boundary as the first scanning start point, the control bias system sequentially increases the output bias current and applies it to the array unit according to the second bias current scanning step size. Under each bias current, the output voltage of the array unit is detected to obtain the second variation curve of the output voltage with the bias current, and the bias current corresponding to the starting point of the first step in the second variation curve is taken as the second scanning start point.
[0059] In step S33, starting from the second scanning start point, the bias system is controlled to sequentially increase the output bias current according to the third bias current scanning step size, that is, decrease the scanning step size of the bias current. The output voltage of the array unit is detected under each bias current to obtain a third variation curve of the output voltage changing with the bias current. A preset number of first current points to be calculated are obtained according to the third variation curve. The preset number of first current points to be calculated are the bias currents corresponding to the starting points of the preset number of steps in the third variation curve. In some embodiments, the preset number can be 3, that is, the first current points to be calculated are the bias currents corresponding to the starting points of the first 3 steps in the third variation curve.
[0060] In step S34, starting from the second scanning start point, the bias system is controlled to sequentially decrease the output bias current and apply it to the array unit according to the third bias current scanning step size. The output voltage of the array unit is detected under each bias current to obtain a fourth variation curve of the output voltage changing with the bias current. The bias current corresponding to the starting point of a preset number of steps in the fourth variation curve is determined as the second current point to be calculated. In some embodiments, the preset number can be 3, that is, the second current point to be calculated is the bias current corresponding to the starting point of the first 3 steps in the fourth variation curve.
[0061] In step S35, the average value of the second scanning starting point, the preset number of first current points to be calculated and the second current points to be calculated is taken as the left boundary of the positive step. Referring to Figure 6, the left boundary of the positive step is shown as point A in Figure 6.
[0062] In step S36, the left boundary of the positive step is used as the third scanning starting point. The bias system is controlled to increase the output bias current sequentially according to the fourth bias current scanning step size and apply it to the array unit. The output voltage of the array unit is detected under each bias current and the output voltage change is calculated. When the output voltage change exceeds a preset threshold, the scanning stops, and a fifth change curve of the output voltage with the bias current is obtained. The positive step boundary and positive step width of each positive step are obtained according to the fifth change curve. In some embodiments, the boundary and width of the first step in the fifth change curve are taken as the positive step boundary and positive step width, respectively. Referring to Figure 6, the positive step boundary is points B and C in Figure 6, and the positive step width is the distance between points B and C.
[0063] In step S37, the bias currents corresponding to the left boundary of the positive step and the right boundary of the negative step are equal in magnitude but opposite in polarity. The bias current and output voltage corresponding to the positive step boundary are also equal in magnitude but opposite in polarity to the negative step boundary. The widths of the positive and negative steps are equal. For example, in Figure 6, point D is the right boundary of the negative step, points E and F are the boundaries of the negative step, and the width of the negative step is the distance between points E and F.
[0064] In step S38, the positive and negative step IV characteristic curves of the corresponding array element are obtained based on the left boundary, positive step boundary, positive step width, right boundary, negative step boundary, and negative step width of the positive step, as shown in Figure 6.
[0065] In step S4, the received quantum voltage output request signal includes the quantum voltage value to be output.
[0066] Referring to Figure 7, in step S5, the quantum voltage control parameters are calculated based on the quantum voltage output request signal and the positive and negative step IV characteristic curves, including:
[0067] S51. Obtain the quantum voltage value to be output based on the quantum voltage output request signal;
[0068] S52. Based on the quantum voltage value to be output and the positive and negative step IV characteristic curves of each array unit, set the bias state of each array unit.
[0069] S53. Determine the required bias current for each array element based on the positive and negative step IV characteristic curves.
[0070] S54. Calculate the quantum voltage control parameters based on the bias current required for each array unit.
[0071] For example, in step S52, the bias state of each array unit is set according to the required output quantum voltage value and the positive and negative step IV characteristic curves of each array unit. The bias state of the array unit includes zero bias state, positive bias state and negative bias state. There is no voltage output in the zero bias state. In the positive bias state, the current direction is the same as the reference direction. In the negative bias state, the current direction is opposite to the reference direction.
[0072] In step S53, the required bias current for each array unit is determined based on the positive and negative step IV characteristic curves. Specifically, based on the bias state of each array unit and the required output quantum voltage value, the bias current corresponding to the voltage value to be output by each array unit is obtained by searching the positive and negative step IV characteristic curves. In some embodiments, the required bias current may be the bias current corresponding to the midpoint of the positive step, negative step, or zero step in the positive and negative step IV characteristic curves.
[0073] In step S54, the quantum voltage control parameters are calculated using the following formula:
[0074] ;
[0075] Where n represents the number of array elements. Indicates the first The value of the output quantum voltage corresponding to each array element. Indicates the first The bias current required for each array element Indicates the bias system towards the first The current input to each array element, Indicates the first The bias state of each array element takes the value 0, +1, or -1. 0 represents a zero-bias state with no voltage output; +1 represents a positive bias state with current flowing in the same direction as the reference direction; and -1 represents a negative bias state with current flowing in the opposite direction to the reference direction. Indicates the first The number of Josephson nodes contained in each array element. Indicates microwave frequency. Represents Josephson's constant. This represents the resistance parameters in the bias system.
[0076] Initial values need to be assigned before calculating the above quantum voltage control parameters, for example:
[0077] .
[0078] In step S6, the quantum voltage synthesis system is controlled to output the required quantum voltage signal according to the quantum voltage control parameters.
[0079] In some embodiments, the method further includes:
[0080] Receive array protection control signals;
[0081] According to the array protection control signal, the output power of the microwave source is controlled to be at its minimum, the bias current output by the bias system is controlled to be 0, and the Josephson array is short-circuited.
[0082] When the Josephson array is not in operation, it is susceptible to electromagnetic interference from the external environment. Therefore, it is necessary to set the output of the bias system to zero, reduce the output power of the microwave source to a minimum (-20dBm), and short-circuit the output terminals of the Josephson array to prevent electrostatic damage to the array.
[0083] Referring to Figure 8, in some embodiments, a quantum voltage output control device based on a Josephson array applying the above method is also provided, comprising:
[0084] Signal receiving module 201 is configured to receive array scanning control signals;
[0085] The zero-step scanning control module 202 is configured to control the quantum voltage synthesis system to perform a zero-step scan according to the array scanning control signal to obtain the zero-step boundary.
[0086] The positive and negative step scanning control module 203 is configured to control the quantum voltage synthesis system to perform positive and negative step scanning based on the zero step boundary, so as to obtain the positive and negative step IV characteristic curves.
[0087] Request module 204 is configured to receive quantum voltage output request signals;
[0088] The control parameter calculation module 205 is configured to calculate the quantum voltage control parameters based on the quantum voltage output request signal and the positive and negative step IV characteristic curves.
[0089] The signal output control module 206 is configured to control the quantum voltage synthesis system to output a quantum voltage signal according to the quantum voltage control parameters.
[0090] The quantum voltage synthesis system includes a bias system, a cryogenic system, a microwave source, and a Josephson array, wherein the Josephson array comprises multiple array elements.
[0091] The device also includes an array protection module, configured as follows:
[0092] Receive array protection control signals;
[0093] According to the array protection control signal, the output power of the microwave source is controlled to be at its minimum, the bias current output by the bias system is controlled to be 0, and the Josephson array is short-circuited.
[0094] The zero-step scanning control module 202 is configured as follows:
[0095] The output power of the microwave source is controlled to be at its minimum, and the first bias current scan step size is set.
[0096] Starting from 0, the bias system is controlled to increase the output bias current sequentially according to the first bias current scanning step size and apply it to the array unit. Under each bias current, the output voltage of the array unit is detected and the output voltage change is calculated. When the output voltage change exceeds a preset threshold, the scanning stops.
[0097] Determine whether the corresponding array unit loses its superconducting properties based on the first curve of the output voltage changing with the bias current.
[0098] If the array element does not lose its superconducting properties, the zero-step boundary is determined based on the first change curve.
[0099] If a step appears in the first curve of the output voltage changing with the bias current, it is determined that the corresponding array unit has not lost its superconducting properties.
[0100] The step is defined as follows: within a certain bias current range, the output voltage remains constant, and at both ends of the bias current range, the corresponding output voltage jumps.
[0101] The zero-step boundary is the bias current corresponding to the starting point of the first step in the first variation curve.
[0102] The positive and negative step scanning control module 203 is configured as follows:
[0103] The output power of the microwave source is controlled to a preset value, and a second bias current scanning step size, a third bias current scanning step size, and a fourth bias current scanning step size are set, wherein the second bias current scanning step size is greater than the third bias current scanning step size.
[0104] Using the zero-step boundary as the first scanning starting point, the bias system is controlled to increase the output bias current sequentially according to the second bias current scanning step size and apply it to the array unit. The output voltage of the array unit is detected under each bias current to obtain the second variation curve of the output voltage with the bias current. The second scanning starting point is obtained according to the second variation curve.
[0105] Starting from the second scanning start point, the bias system is controlled to increase the output bias current sequentially according to the third bias current scanning step size and apply it to the array unit. The output voltage of the array unit is detected under each bias current to obtain the third change curve of the output voltage with the bias current. A preset number of first current points to be calculated are obtained based on the third change curve.
[0106] Starting from the second scanning start point, the bias system is controlled to sequentially decrease the output bias current and apply it to the array unit according to the third bias current scanning step size. The output voltage of the array unit is detected under each bias current to obtain a fourth variation curve of the output voltage with the bias current. A preset number of second current points to be calculated are obtained based on the fourth variation curve.
[0107] The average value of the second scanning starting point, the preset number of the first current points to be calculated and the second current points to be calculated is used as the left boundary of the positive step.
[0108] Using the left boundary of the positive step as the third scanning starting point, the bias system is controlled to increase the output bias current sequentially according to the fourth bias current scanning step and apply it to the array unit. The output voltage of the array unit is detected under each bias current and the output voltage change is calculated. When the output voltage change exceeds a preset threshold, the scanning stops, and a fifth change curve of the output voltage with the bias current is obtained. The boundary of the positive step and the width of the positive step are obtained according to the fifth change curve.
[0109] Based on the principle of symmetry, the right boundary, negative boundary, and negative width of the negative step are obtained according to the left boundary, positive step boundary, and positive step width of the positive step.
[0110] The positive and negative step IV characteristic curves of the corresponding array element are obtained based on the left boundary, positive step boundary, positive step width, right boundary, negative step boundary, and negative step width of the positive step.
[0111] The second scan starting point is the bias current corresponding to the starting point of the first step in the second change curve;
[0112] The first current point to be calculated, which is a preset number, is the bias current corresponding to the starting point of a preset number of steps in the third change curve;
[0113] The preset number of second current points to be calculated are the bias currents corresponding to the starting points of the preset number of steps in the fourth change curve.
[0114] The left boundary of the positive step and the right boundary of the negative step have the same magnitude but opposite polarity of bias current. The bias current and output voltage corresponding to the boundary of the positive step and the boundary of the negative step have the same magnitude but opposite polarity. The width of the positive step and the width of the negative step are the same.
[0115] The control parameter calculation module 205 is configured as follows:
[0116] The quantum voltage value to be output is obtained based on the quantum voltage output request signal;
[0117] Based on the quantum voltage value to be output and the positive and negative step IV characteristic curves of each array unit, the bias state of each array unit is set.
[0118] Based on the positive and negative step IV characteristic curves, determine the required bias current for each array element;
[0119] The quantum voltage control parameters are calculated based on the bias current required for each array element;
[0120] The quantum voltage control parameters are calculated using the following formula:
[0121] ;
[0122] Where n represents the number of array elements. Indicates the first The value of the output quantum voltage corresponding to each array element. Indicates the first The bias current required for each array element Indicates the bias system towards the first The current input to each array element, Indicates the first The bias state of each array element takes the value 0, +1, or -1. 0 represents a zero-bias state with no voltage output; +1 represents a positive bias state with current flowing in the same direction as the reference direction; and -1 represents a negative bias state with current flowing in the opposite direction to the reference direction. Indicates the first The number of Josephson nodes contained in each array element. Indicates microwave frequency. Represents Josephson's constant. This represents the resistance parameters in the bias system.
[0123] The quantum voltage output control method and apparatus based on Josephson arrays provided in the above embodiments have at least the following technical effects:
[0124] By performing zero-step and positive-negative step scans on the Josephson array, more accurate positive-negative step IV characteristic curves are obtained, enabling precise control and output of quantum voltage signals and significantly improving voltage synthesis accuracy and stability.
[0125] (2) By scanning the array elements, the array elements that have lost their superconducting properties can be located.
Claims
1. A quantum voltage output control method based on a Josephson array, applied to a quantum voltage synthesis system based on a Josephson array, the method comprising: Receive array scanning control signals; The quantum voltage synthesis system is controlled to perform a zero-step scan according to the array scanning control signal to obtain the zero-step boundary; Based on the zero-step boundary, the quantum voltage synthesis system is controlled to perform positive and negative step scanning to obtain positive and negative step current-voltage IV characteristic curves. Receive quantum voltage output request signal; Calculate the quantum voltage control parameters based on the quantum voltage output request signal and the positive and negative step IV characteristic curves; The quantum voltage synthesis system is controlled to output a quantum voltage signal according to the quantum voltage control parameters.
2. The method of claim 1, wherein, The quantum voltage synthesis system includes a bias system, a cryogenic system, a microwave source, and a Josephson array, wherein the Josephson array comprises multiple array elements.
3. The method according to claim 2, further comprising: Receive array protection control signals; According to the array protection control signal, the output power of the microwave source is controlled to be at its minimum, the bias current output by the bias system is controlled to be 0, and the Josephson array is short-circuited.
4. The method of claim 2, wherein, The quantum voltage synthesis system is controlled to perform a zero-step scan according to the array scanning control signal to obtain the zero-step boundary, including: The output power of the microwave source is controlled to be at its minimum, and the first bias current scan step size is set. Starting from 0, the bias system is controlled to increase the output bias current sequentially according to the first bias current scanning step size and apply it to the array unit. The output voltage of the array unit is detected under each bias current and the output voltage change is calculated. When the output voltage change exceeds a preset threshold, the scanning stops. Determine whether the corresponding array unit loses its superconducting properties based on the first curve of the output voltage changing with the bias current. In response to the judgment that the array unit has not lost its superconducting properties, the zero-step boundary is determined based on the first change curve.
5. The method of claim 4, wherein, If a step appears in the first curve of the output voltage changing with the bias current, it is determined that the corresponding array unit has not lost its superconducting properties. The step is defined as follows: within a certain bias current range, the output voltage remains constant, and at both ends of the bias current range, the corresponding output voltage jumps. The zero-step boundary is the bias current corresponding to the starting point of the first step in the first variation curve.
6. The method of claim 5, wherein, Based on the zero-step boundary, the quantum voltage synthesis system is controlled to perform positive and negative step scans to obtain positive and negative step IV characteristic curves, including: The output power of the microwave source is controlled to a preset value, and a second bias current scanning step size, a third bias current scanning step size, and a fourth bias current scanning step size are set, wherein the second bias current scanning step size is greater than the third bias current scanning step size. Using the zero-step boundary as the first scanning starting point, the bias system is controlled to increase the output bias current sequentially according to the second bias current scanning step size and apply it to the array unit. The output voltage of the array unit is detected under each bias current to obtain the second variation curve of the output voltage with the bias current. The second scanning starting point is obtained according to the second variation curve. Starting from the second scanning start point, the bias system is controlled to increase the output bias current sequentially according to the third bias current scanning step size and apply it to the array unit. The output voltage of the array unit is detected under each bias current to obtain the third change curve of the output voltage with the bias current. A preset number of first current points to be calculated are obtained based on the third change curve. Starting from the second scanning start point, the bias system is controlled to sequentially decrease the output bias current and apply it to the array unit according to the third bias current scanning step size. The output voltage of the array unit is detected under each bias current to obtain a fourth variation curve of the output voltage with the bias current. A preset number of second current points to be calculated are obtained based on the fourth variation curve. The average value of the second scanning starting point, the preset number of first current points to be calculated and the second current points to be calculated is used as the left boundary of the positive step. Using the left boundary of the positive step as the third scanning starting point, the bias system is controlled to increase the output bias current sequentially according to the fourth bias current scanning step and apply it to the array unit. The output voltage of the array unit is detected under each bias current and the output voltage change is calculated. When the output voltage change exceeds a preset threshold, the scanning stops, and a fifth change curve of the output voltage with the bias current is obtained. The boundary of the positive step and the width of the positive step are obtained according to the fifth change curve. Based on the principle of symmetry, the right boundary, negative boundary, and negative width of the negative step are obtained from the left boundary, positive step boundary, and positive step width. The positive and negative step IV characteristic curves of the corresponding array element are obtained based on the left boundary, positive step boundary, positive step width, right boundary, negative step boundary, and negative step width of the positive step.
7. The method of claim 6, wherein, The second scan starting point is the bias current corresponding to the starting point of the first step in the second change curve; The first current point to be calculated, which is a preset number, is the bias current corresponding to the starting point of a preset number of steps in the third change curve; The preset number of second current points to be calculated are the bias currents corresponding to the starting points of the preset number of steps in the fourth change curve.
8. The method of claim 6, wherein, The left boundary of the positive step and the right boundary of the negative step have the same magnitude but opposite polarity of bias current. The bias current and output voltage corresponding to the boundary of the positive step and the boundary of the negative step have the same magnitude but opposite polarity. The width of the positive step and the width of the negative step are equal.
9. The method of claim 2, wherein, Based on the quantum voltage output request signal and the positive and negative step IV characteristic curves, the quantum voltage control parameters are calculated, including: Based on the quantum voltage output request signal, the quantum voltage value to be output is obtained; Based on the quantum voltage value to be output and the positive and negative step IV characteristic curves of each array unit, the bias state of each array unit is set. Based on the positive and negative step IV characteristic curves, determine the required bias current for each array element; The quantum voltage control parameters are calculated based on the bias current required for each array element; The quantum voltage control parameters are calculated using the following formula: ； wherein n represents the number of junction array units, represents the 1 a value of a quantum voltage output by a junction array, represents the 1 a bias current required for a junction array, representing the bias system to the first a current input to the junction array, represents the 1 a bias state of a junction array unit, taking values of 0, +1 or -1, 0 representing that the junction array unit is in a zero bias state without voltage output, +1 indicating that the junction array unit is in a positive bias state with the same current direction as the reference direction, and -1 indicating that the junction array unit is in a negative bias state with the opposite current direction to the reference direction, represents the 1 The number of Josephson junctions included in a junction array, denotes a microwave frequency, denotes the Josephson constant, This represents the resistance parameters in the bias system.
10. A quantum voltage output control device based on a Josephson array applying the method of any one of claims 1-9, comprising: The signal receiving module is configured to receive array scanning control signals; The zero-step scanning control module is configured to control the quantum voltage synthesis system to perform a zero-step scan according to the array scanning control signal, so as to obtain the zero-step boundary. The positive and negative step scanning control module is configured to control the quantum voltage synthesis system to perform positive and negative step scanning based on the zero step boundary, so as to obtain the positive and negative step current-voltage IV characteristic curves. The request module is configured to receive quantum voltage output request signals; The control parameter calculation module is configured to calculate the quantum voltage control parameters based on the quantum voltage output request signal and the positive and negative step IV characteristic curves. The signal output control module is configured to control the quantum voltage synthesis system to output a quantum voltage signal according to the quantum voltage control parameters.