Quantum bit control signal generation method and apparatus, and quantum computer

Abstract

The application belongs to the technical field of quantum measurement and control, and discloses a method and device for generating a quantum bit control signal and a quantum computer. The method for generating a quantum bit control signal comprises: obtaining delay information of a digital-to-analog conversion module outputting a first control signal; wherein the first control signal is used for controlling the frequency or quantum state of a quantum bit, and the delay information is time information of the digital-to-analog conversion module delaying the output of the first control signal; determining the waveform curve of a second control signal to be output to the quantum bit according to the delay information and the waveform data of the first control signal; sampling the waveform curve to obtain sampling data; and outputting a corresponding control signal according to the sampling data. The application can provide a quantum bit with a control signal whose delay precision meets the control precision requirement.

Description

Technical Field

[0001] This application relates to the field of quantum measurement and control technology, and in particular to a method, apparatus and quantum computer for generating qubit control signals. Background Technology

[0002] Quantum computing is a novel computing method that combines quantum mechanics with computer science, performing calculations by manipulating quantum information units in accordance with the laws of quantum mechanics. It uses qubits, composed of microscopic particles, as its basic units, exhibiting properties such as quantum superposition and entanglement. Furthermore, through the controlled evolution of quantum states, quantum computing can achieve information encoding and computational storage, possessing an unparalleled capacity for information carrying and superior parallel computing capabilities compared to classical computing.

[0003] The core of a quantum computer is a quantum chip, which contains a large number of qubits. Each qubit is composed of specific hardware circuits set on the quantum chip. Each qubit has at least two distinguishable logical states. Based on quantum algorithms, the logical states of qubits can be changed in a controllable manner, thereby realizing quantum computing.

[0004] A quantum computer also includes a control system that provides a control environment for the quantum chip. This control system mainly consists of hardware devices located at room temperature and cryogenic devices and signal transmission lines located within a dilution refrigerator. After the quantum chip is packaged, it is fixed in the lowest cryogenic layer of the dilution refrigerator and ultimately connected to the room temperature hardware devices via coaxial lines between the layers. In this control system, two types of lines are mainly used to control the quantum state of the qubits: a first transmission line for driving the quantum state of the qubits and a second transmission line for controlling the frequency of the qubits.

[0005] Due to the different cable lengths of different transmission lines and the addition of different microwave devices on the lines, the transmission delay of signals on different lines is different. As a result, different control signals cannot be transmitted to the quantum chip according to the designed timing. In order to ensure that the control signals on the first and second transmission lines are transmitted to the quantum chip at the same time, it is usually necessary to increase the delay of the control signals with low transmission delay. That is, the output channel of the measurement and control system outputs the control signal with a delay. However, the quantum chip has high timing requirements for the control signals, and the delay accuracy needs to be below 100 picoseconds.

[0006] In existing technologies, the method of delaying the output of control signals usually involves adding a delay at the front end of the control signal. The accuracy of the delay is determined by the sampling rate of the signal generator in the measurement and control system, which is the derivative of the sampling rate. For example, when the sampling rate is 1.2 GHz, its sampling resolution is 830 picoseconds. Even if the sampling rate is increased to 3.2 GHz, its sampling resolution is 310 picoseconds. However, the accuracy requirement of the control signal for qubits is within 100 picoseconds. Therefore, it is impossible to meet the accuracy requirements of the control signal for qubits.

[0007] Therefore, there is an urgent need to provide a device or method for obtaining a control signal with a delay accuracy that can meet the precision requirements of qubit control.

[0008] It should be noted that the information disclosed in the background section of this application is intended only to enhance the understanding of the general background of this application, and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0009] The purpose of this application is to provide a method, apparatus and quantum computer for generating qubit control signals, which can be used to obtain control signals with delay accuracy that meet the control accuracy requirements of qubits.

[0010] To achieve the above objectives, this application proposes a method for generating a qubit control signal, comprising:

[0011] Acquire the delay information of the first control signal output by the digital-to-analog converter module; wherein, the first control signal is used to control the frequency or quantum state of the qubit, and the delay information is the time information of the digital-to-analog converter module delaying the output of the first control signal;

[0012] Based on the delay information and the waveform data of the first control signal, the waveform curve of the second control signal to be output to the quantum bit is determined;

[0013] The waveform curve is sampled to obtain sampled data;

[0014] The corresponding control signal is output based on the sampled data.

[0015] The method for generating the quantum bit control signal as described above, preferably, involves obtaining the delay information of the first control signal output by the digital-to-analog converter module, specifically including:

[0016] Send the experimental waveforms of two first control signals with preset delays to the digital-to-analog converter module;

[0017] The measurement delay of the first control signal output from the two output channels of the digital-to-analog converter module is obtained;

[0018] The measurement delay is determined to be the delay information.

[0019] In the method for generating a qubit control signal as described above, preferably, the first control signal includes a frequency control signal and a quantum state control signal. The frequency control signal is used to control the frequency of the qubit to a target frequency, and the quantum state control signal is used to control the quantum state of the same qubit to a target quantum state. The waveform data of the frequency control signal and the quantum state control signal are determined based on the target frequency and the target quantum state, respectively.

[0020] In the method for generating the quantum bit control signal as described above, preferably, when the frequency control signal is transmitted to the quantum processor before the quantum state control signal, the waveform of the second control signal is formed by splicing the waveform of the frequency control signal and an empty waveform located before the time information of the frequency control signal; wherein, the time information of the empty waveform corresponds to the delay information.

[0021] In the method for generating the quantum bit control signal as described above, preferably, when the quantum state control signal is transmitted to the quantum processor before the frequency control signal, the waveform of the second control signal is formed by splicing the waveform of the quantum state control signal and an empty waveform preceding the time information of the quantum state control signal; wherein, the time information of the empty waveform corresponds to the delay information.

[0022] In the method for generating the quantum bit control signal as described above, preferably, the amplitude of the empty waveform is a preset fixed value.

[0023] The method for generating qubit control signals as described above, preferably, involves determining the waveform curve of the second control signal to be output to the qubit based on the delay information and the waveform data of the first control signal, specifically including:

[0024] Obtain the first waveform curve corresponding to the waveform data of the first control signal, wherein the first waveform curve is a curve characterizing the waveform amplitude of the first control signal and the corresponding time.

[0025] Obtain a first straight line between the amplitude of the empty waveform and the delay information;

[0026] The waveform curve is obtained by splicing the first straight line and the first waveform curve.

[0027] In the preferred embodiment of the method for generating qubit control signals as described above, the step of sampling the waveform curve to obtain sampling data specifically includes:

[0028] The waveform curve is sampled according to the sampling rate of the digital-to-analog conversion module to obtain the sampled data.

[0029] In the preferred embodiment of the method for generating qubit control signals as described above, the step of outputting a corresponding control signal based on the sampled data specifically includes:

[0030] The sampled data is output to the digital-to-analog conversion module;

[0031] The digital-to-analog conversion module outputs a corresponding control signal based on the sampled data.

[0032] Another aspect of this application provides a device for generating quantum bit control signals, comprising:

[0033] A measurement module is used to acquire delay information of the first control signal output by the digital-to-analog converter module; wherein, the first control signal is used to control the frequency or quantum state of the qubit, and the delay information is the time information of the digital-to-analog converter module delaying the output of the first control signal;

[0034] The data processing sampling module is used to determine the waveform curve of the second control signal to be output to the quantum bit based on the delay information and the waveform data of the first control signal;

[0035] The sampling module is used to sample the waveform curve to obtain sampling data;

[0036] The digital-to-analog conversion module is used to output corresponding control signals based on the sampled data.

[0037] In another aspect, this application provides a quantum computer that outputs control signals for controlling qubits on a quantum processor using any of the above-described methods for generating qubit control signals, or includes the above-described qubit control signal generating apparatus and a quantum processor, wherein the qubit control signal generating apparatus is used to provide control signals for the qubits on the quantum processor.

[0038] Compared with the prior art, this application has the following beneficial effects:

[0039] This application constructs the waveform curve of the second control signal for each qubit's control signal by using the measured delay information and the first control signal determined by the control requirements. That is, the waveform curve of the second control signal is obtained based on the measured delay information, and the waveform curve is sampled to obtain sampled data. The corresponding control signal is output based on the sampled data. This ensures that the waveform curves of the control signal and the second control signal are completely consistent and are not affected by the sampling rate, which makes the delay accuracy of the control signal meet the control accuracy requirements of the qubit. Attached Figure Description

[0040] Figure 1 This is a schematic diagram illustrating the effect of delay achieved by shifting the sampled waveform in existing technologies.

[0041] Figure 2This is a flowchart illustrating a method for generating a quantum bit control signal according to an embodiment of this application.

[0042] Figure 3 This is a schematic diagram of the waveform of a second control signal according to an embodiment of this application;

[0043] Figure 4 This is a schematic diagram illustrating a method for sampling a waveform curve according to an embodiment of this application;

[0044] Figure 5 This is a schematic diagram of a process for obtaining a waveform curve according to an embodiment of this application;

[0045] Figure 6 This is a schematic diagram of the functional modules of a quantum bit control signal generation device proposed in an embodiment of this application.

[0046] 10 - Measurement module, 20 - Data processing module, 30 - Sampling module, 40 - Digital-to-analog conversion module. Detailed Implementation

[0047] The specific embodiments of this application will be described in more detail below with reference to the schematic diagrams. The advantages and features of this application will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this application.

[0048] In the description of this application, it should be understood that the terms "center", "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] Most existing quantum computers employ a combination of a host computer, a quantum control system, and quantum chips to perform quantum computing tasks. Typically, the host computer receives the user's quantum computing task, processes it, and forms a quantum circuit. This quantum circuit is then mapped onto the topology of the corresponding quantum chip. The quantum circuit contains the quantum logic gates required for the task, the measurement operations for the final quantum computing result, and the timing sequence of each operation. Upon receiving this information from the quantum circuit, the quantum control system translates it into corresponding instructions to enable the relevant hardware devices to operate and complete the quantum computing task.

[0051] Generally, a quantum chip contains multiple qubits and data transmission lines. Each qubit includes a detector and a qubit device coupled to each other. The qubit device can be an artificial superconducting qubit constructed using a superconducting Josephson junction and capacitance to ground, and the detector can be a resonant cavity. The qubit device has a first control signal line and a second control signal line, and the detector coupled to the qubit device has a third control signal line. The first control signal line transmits quantum state control signals to regulate the quantum state information of the qubit device; the second control signal line transmits frequency control signals to regulate the frequency parameters of the qubit device; and the third control signal line transmits both measurement signals for reading from the detector and outputs the readback signals returned by the detector, thus achieving indirect reading and measurement of the qubit device's state. Therefore, the quantum control system used for qubit manipulation and measurement in the quantum chip needs to generate and output three control signals, respectively, to the first to third control signal lines to achieve the manipulation and measurement of the qubits in the quantum chip.

[0052] Because the cable lengths of different control signal lines are different and different microwave devices are added to the lines, the transmission delay of the signals on different lines is different. As a result, different control signals cannot be transmitted to the quantum chip in the designed timing. In order to ensure that the control signals on the first transmission line and the second transmission line are transmitted to the quantum chip at the same time, it is usually necessary to add a delay to the control signal that is prioritized to be transmitted to the quantum chip. That is, the output channel of the measurement and control system outputs the control signal with a delay.

[0053] In existing technologies, methods for delaying the output of control signals typically involve adding a delay waveform to the front end of the control signal. This delay waveform is a waveform with zero amplitude, and the delay time is determined. The waveform of the control signal is preset; the delay can be understood as a time shift of the control signal waveform. The accuracy of the delay waveform is determined by the sampling rate of the signal generator in the measurement and control system, and is the derivative of the sampling rate. For example, at a sampling rate of 1.2 GHz, the sampling resolution is 830 picoseconds. Even if the sampling rate is increased to 3.2 GHz, the sampling resolution is only 310 picoseconds. This means the delay accuracy is still much greater than the 100 picosecond accuracy requirement for the control signal by the qubit, causing the delayed control signal to deviate from the expected control effect on the qubit.

[0054] As attached Figure 1 The high-low flat-top wave waveform shown illustrates a delay method and its effect for control signal waveforms. The horizontal axis represents time t, and the vertical axis represents the waveform amplitude parameter. Each dot in the signal waveform corresponds to an amplitude parameter with a minimum sampling resolution. C20 represents an initial signal waveform, and C30 represents the effect of shifting C20 to the right by Δt, where Δt is the derivative of the sampling rate of the signal generator, which can be understood as the sampling resolution—the minimum time resolution for each waveform shift. C10 represents the target control signal waveform. It can be observed that, affected by the waveform shift accuracy, the shifted waveform of C20 deviates from the target control signal waveform. For the high-low flat-top wave signal waveform, the amplitude parameters of the waveform during the low-level delay period and the waveform during the high-level duration are fixed and can be considered unaffected by the delay accuracy. The amplitude parameter during the rising edge period is directly affected by the delay accuracy. When the delay accuracy is not met, the amplitude parameter difference is very large, reducing the control accuracy of the qubits.

[0055] Among them, the appendix Figure 1 This example only illustrates a Gaussian flat-top wave. For other waveform shapes, when the sampling resolution is low, the waveform translation accuracy is also low, which will cause the waveform parameters of the translated control signal to deviate from the waveform parameters of the target control signal. This example will not elaborate on these points.

[0056] As attached Figure 2 As shown in the figure, this application provides a method for generating a quantum bit control signal, including the following steps:

[0057] Step S10: Obtain the delay information of the first control signal output by the digital-to-analog converter module; wherein, the first control signal is used to control the frequency or quantum state of the qubit, and the delay information is the time information of the digital-to-analog converter module delaying the output of the first control signal.

[0058] The varying cable lengths of different control signal lines for the same qubit, along with the addition of different microwave devices along the lines, result in different transmission delays for the first control signal controlling the qubit's frequency and the first control signal controlling the qubit's quantum state on different lines. Delaying the output of the first control signal that is preferentially transmitted to the qubit ensures synchronized control of the qubit. For all control signal lines, the delay information for both the first control signal controlling the qubit's frequency and the first control signal controlling the qubit's quantum state needs to be determined through measurement. It should be noted that for the first control signal controlling the frequency of the same qubit and the first control signal controlling the quantum state of that qubit, only one of the first control signals needs to be delayed; this delay information can be obtained through measurement.

[0059] Step S20: Determine the waveform curve of the second control signal to be output to the qubit based on the delay information and the waveform data of the first control signal.

[0060] Combined with appendix Figure 3 As shown in the figure, C10 represents the waveform of the first control signal, which is used to control the frequency or quantum state of the qubit. This signal is preset, meaning its waveform curve is predetermined. After obtaining the delay information through measurement, the waveform curve corresponding to the delay information is stitched before the waveform curve of the control signal to form the waveform curve of the second control signal transmitted to the qubit. Here, t1 represents the delay information, and the waveform curve of t1 is an empty waveform with a fixed amplitude in the attached figure. t2 represents the start time and duration of the first control waveform. When stitching the empty waveform and the waveform of the first control signal, the stitching is performed based on the time information.

[0061] It should be added that, compared to the first control signal, the second control signal adds a waveform curve corresponding to the delay information. The control waveform used to control the frequency or quantum state of the qubit is the same. The waveform curve corresponding to the delay information is typically an empty waveform, and its amplitude is set to a fixed value. This ensures that when the empty waveform is transmitted to the qubit, it does not change the qubit's frequency or quantum state. The signal waveform following the empty waveform, corresponding to the first control signal, takes effect when transmitted to the qubit, adjusting the qubit's frequency or quantum state. (Appendix) Figure 3 The zero amplitude of the empty waveform shown in the diagram is only an illustration of a fixed value; it can also be other fixed values.

[0062] Step S30: Sample the waveform curve to obtain sampled data.

[0063] Continue to combine with the appendix Figure 3 and attached Figure 4As shown, the waveform curve of the second control signal obtained by splicing corresponds to the control signal with the same delay to be transmitted to the qubit. By sampling this waveform curve, sampled data is obtained, ensuring that the obtained sampled data corresponds one-to-one with and is completely identical to the waveform parameters of the second control signal.

[0064] Specifically, sampling involves determining the sampling point and the sampled data at that point on the waveform curve of the second control signal based on the sampling rate of the digital-to-analog converter module, as shown in the attached figure. Figure 4 The example dots are shown in the image. Taking a sampling rate of 1.2 GHz as an example, a sampling point is determined every 830 picoseconds on the waveform curve to obtain the corresponding sampling data, and then the sampling data representing the second control signal is obtained.

[0065] Step S40: Output the corresponding control signal based on the sampled data.

[0066] The sampled data is sent to the digital-to-analog converter module. The digital-to-analog converter module outputs the corresponding control signal based on the sampled data. The output control signal is generated based on the sampled data obtained by sampling the waveform curve of the second control signal, ensuring that the output control signal is the same as the second control signal, thereby ensuring the accuracy of the control signal transmitted to the quantum bit.

[0067] For each qubit's control signal, the waveform curve of the second control signal is constructed by determining the delay information and the first control signal. That is, the waveform curve of the second control signal is obtained based on the measured delay information, and the waveform curve is sampled to obtain sampled data. The corresponding control signal is output based on the sampled data, ensuring that the waveform curve of the control signal and the second control signal are completely consistent and are not affected by the sampling rate. This makes the delay accuracy of the control signal meet the control accuracy requirements of the qubit.

[0068] As one embodiment of this application, the first control signal includes a frequency control signal and a quantum state control signal. The frequency control signal is used to control the frequency of the qubit to a target frequency, and the quantum state control signal is used to control the quantum state of the same qubit to a target quantum state. The waveform data of the frequency control signal and the quantum state control signal are determined based on the target frequency and the target quantum state.

[0069] In the field of quantum computing, a qubit is a two-level resonant system built on nonlinear inductors and capacitors. It has several energy levels and energy level transition frequencies. Energy level transitions require transition energy. The energy level corresponds to the eigenstate in the quantum state of the qubit, and the transition frequency is the frequency of the qubit, which is controlled by applying a square wave signal. The transition energy is usually provided by a microwave signal, that is, controlled by applying a quantum state control signal.

[0070] When controlling the same qubit, the frequency of the qubit is first adjusted to the target frequency using a frequency control signal, and then the quantum state of the qubit is adjusted to the target quantum state using a quantum state control signal. It should be noted that this sequence only describes the principle of qubit control and does not represent the order in which the frequency control signal and the quantum state control signal are transmitted. In actual operation, the frequency control signal and the quantum state control signal need to be transmitted to the same qubit simultaneously.

[0071] After obtaining the delay information of the first control signal controlling the frequency and quantum state of the same qubit through measurement, when the frequency control signal is transmitted to the quantum processor before the quantum state control signal, the waveform of the second control signal is formed by splicing the waveform of the frequency control signal and an empty waveform preceding the time information of the frequency control signal; wherein, the time information of the empty waveform corresponds to the delay information. When the quantum state control signal is transmitted to the quantum processor before the frequency control signal, the waveform of the second control signal is formed by splicing the waveform of the quantum state control signal and an empty waveform preceding the time information of the quantum state control signal; wherein, the time information of the empty waveform corresponds to the delay information.

[0072] It should be added that this embodiment uses the first control signal controlling the frequency and quantum state of the same qubit as an example to describe the frequency control signal and the quantum state control signal. When two qubits perform a two-bit gate operation, the first control signals controlling the frequencies of the two qubits also need to be synchronized through delay information, that is, one of the two frequency control signals also needs to be spliced ​​with an empty waveform before the control waveform; similarly, the first control signals controlling the two quantum states also need to be synchronized through delay information, that is, one of the two quantum state control signals also needs to be spliced ​​with an empty waveform before the control waveform. The method for splicing the empty waveform also adopts the above-described method for generating qubit control signals.

[0073] Specifically, based on the delay information obtained from measurements, the control signal prioritized for transmission to the qubit is delayed; that is, an empty waveform is appended before the control waveform, and the timing information of the empty waveform is the same as the delay information. In this embodiment, the amplitude of the empty waveform is a preset fixed value. The amplitude information of the frequency control signal and the quantum state control signal corresponds to the frequency and quantum state of the qubit. Setting the amplitude of the empty waveform appended before the control waveform to a preset fixed value ensures that when the empty waveform is transmitted to the qubit, it will not change the frequency or quantum state of the qubit. When the signal waveform corresponding to the first control signal after the empty waveform is transmitted to the qubit, it takes effect and adjusts the frequency or quantum state of the qubit.

[0074] It should be added that the preset fixed value can be zero or other non-zero values. When a delay is required for the frequency control signal, the amplitude of the empty waveform preceding the signal waveform can be zero or other non-zero values, as long as the frequency of the qubit is at the preset frequency and the frequency of the qubit is not changed. When a delay is required for the quantum state control signal, the amplitude of the empty waveform preceding the signal waveform is usually set to zero.

[0075] As attached Figure 5 As shown, in one embodiment, determining the waveform curve of the second control signal to be output to the qubit based on the delay information and the waveform data of the first control signal specifically includes the following steps:

[0076] Step S210: Obtain the first waveform curve corresponding to the waveform data of the first control signal, wherein the first waveform curve is a curve representing the waveform amplitude of the first control signal and the corresponding time.

[0077] Step S220: Obtain the first straight line between the amplitude of the empty waveform and the delay information.

[0078] Step S230: Piece together the first straight line and the first waveform curve to obtain the waveform curve.

[0079] The first control signal is a defined square wave or sine wave signal, and its waveform data is known, specifically the relationship between waveform amplitude and corresponding time. The amplitude of the empty waveform is a preset fixed value, mainly reflecting its time delay information; it is a first straight line with a preset fixed amplitude. The empty waveform is spliced ​​before the first control signal according to the time information; the spliced ​​waveform curve is shown in the attached figure. Figure 3 As shown.

[0080] Appendix Figure 3 In the coordinate system, the horizontal axis represents time information, and the vertical axis represents waveform amplitude information. The start time of the first control signal waveform is aligned with the end time of the empty waveform and then spliced ​​together. The spliced ​​waveform curve is the waveform curve of the second control signal that needs to be transmitted to the qubit. Based on this waveform curve, sampling is performed, and the sampled data is output to the digital-to-analog converter module to ensure that the control signal output by the digital-to-analog converter module is the same as the second control signal, thereby ensuring that the delay accuracy meets the requirements of the qubit.

[0081] In this embodiment, after obtaining the waveform curve of the second control signal by splicing, the step of sampling the waveform curve to obtain sampling data specifically includes: sampling the waveform curve according to the sampling rate of the digital-to-analog converter module to obtain the sampling data. That is, several sampling points are determined on the waveform curve of the second control signal according to the derivative of the sampling rate of the digital-to-analog converter module, and sampling data of each sampling point is obtained. The sampling data is sampled from the waveform curve of the second control signal to ensure the accuracy of the sampling data transmitted to the digital-to-analog converter module.

[0082] After sampling data is obtained by sampling the waveform curve of the second control signal, the step of outputting the corresponding control signal based on the sampled data specifically includes the following steps:

[0083] Step S410: Output the sampled data to the digital-to-analog conversion module.

[0084] Step S420: The digital-to-analog conversion module outputs a corresponding control signal based on the sampled data.

[0085] The digital-to-analog converter receives the sampled data and outputs the corresponding control signal based on the sampled data. It can be understood that the sampled data is sampled from the waveform curve of the second control signal, and the waveform curve of the second control signal is obtained by splicing the delay information obtained by measurement. That is, the control signal output based on the sampled data is completely consistent with the waveform curve of the second control signal and is not affected by the sampling rate. This avoids the poor delay accuracy caused by the sampling rate when shifting the signal waveform.

[0086] As attached Figure 6 As shown, based on the same application concept, this application embodiment also provides a qubit control signal generation device, including: a measurement module 10, used to acquire delay information of a first control signal output by a digital-to-analog converter module 40; wherein, the first control signal is used to control the frequency or quantum state of the qubit, and the delay information is the time information of the delay in the output of the first control signal by the digital-to-analog converter module; a data processing module 20, used to determine the waveform curve of a second control signal to be output to the qubit based on the delay information and the waveform data of the first control signal; a sampling module 30, used to sample the waveform curve to obtain sampling data; and a digital-to-analog converter module 40, used to output a corresponding control signal based on the sampling data.

[0087] The measurement module 10, data processing module 20, and sampling module 30 can be functional modules integrated into the host computer or functional modules integrated into an FPGA (Field-Programmable Gate Array). The digital-to-analog converter module 40 can be a DAC (Digital to Analog Converter).

[0088] When the measurement module 10, data processing module 20, and sampling module 30 are integrated into the host computer, the host computer splices the waveform data corresponding to the delay information with the waveform data of the first control signal, samples the spliced ​​waveform data, and sends the sampled data to the digital-to-analog converter module 40, which then outputs the corresponding control signal.

[0089] When the measurement module 10, data processing module 20, and sampling module 30 are integrated into the FPGA, the waveform data splicing and sampling operations are completed by the FPGA, and the sampled data is sent to the digital-to-analog converter module 40, which then outputs the corresponding control signal.

[0090] Based on the same concept, embodiments of this application also provide a quantum computer that outputs control signals for controlling qubits on a quantum processor using any of the above-described methods for generating qubit control signals, or includes the above-described qubit control signal generating apparatus and a quantum processor, wherein the qubit control signal generating apparatus is used to provide control signals for the qubits on the quantum processor.

[0091] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," or "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0092] The above are merely preferred embodiments of this application and do not constitute any limitation on this application. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in this application without departing from the scope of the technical solutions of this application shall still fall within the protection scope of this application.

Claims

1. A method for generating a quantum bit control signal, characterized in that, include: Acquire the delay information of the first control signal output by the digital-to-analog converter module; wherein, the first control signal is used to control the frequency or quantum state of the qubit, and the delay information is the time information of the digital-to-analog converter module delaying the output of the first control signal; Based on the time information, the waveform curve corresponding to the delay information is spliced ​​before the waveform curve of the first control signal to obtain the waveform curve of the second control signal to be output to the quantum bit, wherein the waveform curve corresponding to the delay information is an empty waveform with a preset fixed amplitude. The waveform curve of the second control signal is sampled according to the sampling rate of the digital-to-analog converter module to obtain sampled data, which is then output to the digital-to-analog converter module. The digital-to-analog conversion module outputs corresponding control signals based on the sampled data.

2. The method for generating quantum bit control signals as described in claim 1, characterized in that, Obtain the delay information of the first control signal output by the digital-to-analog converter module, specifically including: Send the experimental waveforms of two first control signals with preset delays to the digital-to-analog converter module; The measurement delay of the first control signal output from the two output channels of the digital-to-analog converter module is obtained; The measurement delay is determined to be the delay information.

3. The method for generating quantum bit control signals as described in claim 1, characterized in that, The first control signal includes a frequency control signal and a quantum state control signal. The frequency control signal is used to control the frequency of the qubit to a target frequency, and the quantum state control signal is used to control the quantum state of the same qubit to a target quantum state. The waveform data of the frequency control signal and the quantum state control signal are determined based on the target frequency and the target quantum state, respectively.

4. The method for generating quantum bit control signals as described in claim 3, characterized in that, When the frequency control signal is transmitted to the quantum processor before the quantum state control signal, the waveform of the second control signal is formed by splicing the waveform of the frequency control signal and an empty waveform preceding the time information of the frequency control signal; wherein the time information of the empty waveform corresponds to the delay information.

5. The method for generating a quantum bit control signal as described in claim 3, characterized in that, When the quantum state control signal is transmitted to the quantum processor before the frequency control signal, the waveform of the second control signal is formed by splicing the waveform of the quantum state control signal and an empty waveform preceding the time information of the quantum state control signal; wherein the time information of the empty waveform corresponds to the delay information.

6. The method for generating a quantum bit control signal as described in claim 1, characterized in that, The step of stitching the waveform curve corresponding to the delay information before the waveform curve of the first control signal based on the time information to obtain the waveform curve of the second control signal to be output to the qubit specifically includes: Obtain the first waveform curve corresponding to the waveform data of the first control signal, wherein the first waveform curve is a curve characterizing the waveform amplitude of the first control signal and the corresponding time. Obtain a first straight line between the amplitude of the empty waveform and the delay information; The waveform curve is obtained by splicing the first straight line and the first waveform curve.

7. A device for generating quantum bit control signals, characterized in that, include: A measurement module is used to acquire delay information of the first control signal output by the digital-to-analog converter module; wherein, the first control signal is used to control the frequency or quantum state of the qubit, and the delay information is the time information of the digital-to-analog converter module delaying the output of the first control signal; The data processing module is used to stitch the waveform curve corresponding to the delay information before the waveform curve of the first control signal according to the time information to obtain the waveform curve of the second control signal to be output to the quantum bit, wherein the waveform curve corresponding to the delay information is an empty waveform with a preset fixed amplitude. The sampling module is used to sample the waveform curve of the second control signal according to the sampling rate of the digital-to-analog converter module to obtain sampled data, and output it to the digital-to-analog converter module; The digital-to-analog conversion module is used to output corresponding control signals based on the sampled data.

8. A quantum computer, characterized in that, The method for generating qubit control signals as described in any one of claims 1-6 outputs control signals for controlling qubits on a quantum processor, or includes a qubit control signal generation device as described in claim 7 and a quantum processor, wherein the qubit control signal generation device is used to provide control signals for qubits on the quantum processor.

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