Measurement and control system of quantum computer, quantum computer and monitoring method

Abstract

The invention discloses a measurement and control system of a quantum computer, the quantum computer and a monitoring method. The system comprises a signal generation unit, a signal monitoring unit and a quantum analyzer, the signal generation unit is used for generating a first signal to a quantum bit in a quantum processing unit of the quantum computer so as to perform a corresponding effect on the quantum bit; the input end of the signal monitoring unit is connected with the signal generation unit, and the output end is connected with the quantum analyzer and the quantum processing unit. The coupling unit is used for coupling out the first signal part, demodulating the first signal part, outputting the demodulated first signal part to the quantum analyzer, and outputting the rest first signal part to the quantum processing unit; and the quantum analyzer is used for collecting and analyzing the demodulated signal output by the signal monitoring unit. According to the invention, real-time monitoring of the first signal can be realized, and in the monitoring process, the connection relationship of the measurement and control system of the quantum computer does not need to be additionally changed, so that the risk of misconnection possibly existing in a recovery circuit after inspection is also avoided.

Description

Technical Field

[0001] The present invention relates to the field of quantum information technology, and particularly to a measurement and control system for a quantum computer, a quantum computer, and a monitoring method. Background Art

[0002] In current quantum computers, users interact with a quantum measurement and control system through a host computer, a gigabit Ethernet switch. Specifically, the host computer transmits any waveform to be emitted to an arbitrary waveform generator (AWG) in the quantum measurement and control system. The quantum analyzer in the quantum measurement and control system collects the signals of the quantum processing unit and sends the collected signals to the host computer for analysis and processing, so as to obtain the current state of the quantum bit. During the experiment, when it is suspected that software or hardware problems cause the actual emitted waveform of the AWG not to meet the expectations, it is necessary to check and troubleshoot the experimental waveform to find the cause of the failure.

[0003] In a typical example of checking and troubleshooting, assume that the cavity frequency of the quantum bit has been found, and now its energy spectrum is to be found. On the control signal path, the AWG first emits a section of control waveform, which is mixed with the pulse signal emitted by the microwave source to form a high-frequency signal (i.e., the control signal) and enters the quantum processing unit to try to excite the quantum bit. Then, a read-in signal transmission module is used to emit a read-in signal to the quantum bit to read the state of the cavity and then the state of the quantum bit. Among them, the read-in signal transmission module includes an AWG (not the same AWG as the AWG on the control signal path) and an IQ mixer. The waveform emitted by the AWG and the pulse signal emitted by the microwave source are mixed by the IQ mixer to obtain the read-in signal. When the energy spectrum cannot be scanned out, the following situations are generally suspected: 1. The control signal is not emitted; 2. The read-in signal is not emitted; 3. The relative order of the read-in signal and the control signal is incorrect.

[0004] In the above checking and troubleshooting process, in order to check whether the signal meets the expectations, the general solution is to change the connection wires, directly connect the output port of the AWG to an external oscilloscope, and check whether the actually output waveform conforms to the waveform theoretically generated by the software and whether the time sequence between the signals is correct through the oscilloscope. The implementation process of such a checking scheme is relatively cumbersome. Especially when there are multiple quantum bits, the number of channels to be checked increases, more lines need to be changed, and there is also a risk of incorrect restoration of the circuit connection after the check, resulting in low efficiency and being not conducive to expansion. Summary of the Invention

[0005] In view of the above problems, the present invention is proposed to provide a measurement and control system for a quantum computer, a quantum computer, and a monitoring method that overcome the above problems or at least partially solve the above problems.

[0006] In a first aspect, an embodiment of the present invention provides a measurement and control system for a quantum computer, including: a signal generation unit, a signal monitoring unit, and a quantum analyzer;

[0007] The signal generation unit is configured to generate a first signal for qubits in a quantum processing unit of the quantum computer to perform corresponding operations on the qubits;

[0008] The input end of the signal monitoring unit is connected to the signal generation unit, and the output end is respectively connected to the quantum analyzer and the quantum processing unit; the signal monitoring unit is configured to partially couple out a part of the first signal generated by the signal generation unit, demodulate it and output it to the quantum analyzer, and output the remaining first signal to the quantum processing unit;

[0009] The quantum analyzer is configured to collect and analyze the demodulated signal output by the control signal monitoring unit to monitor the first signal.

[0010] In an embodiment, the signal monitoring unit includes: a signal distribution device and a demodulation mixer; where:

[0011] The signal distribution device is connected between the signal generation unit and the quantum processing unit;

[0012] The input ends of the demodulation mixer are respectively connected to the signal distribution device and the signal generation unit, and the output end of the demodulation mixer is connected to the quantum analyzer;

[0013] The signal distribution device is configured to couple out a part of the first signal generated by the signal generation unit and output it to the demodulation mixer, and output the remaining first signal to the quantum processing unit;

[0014] The demodulation mixer is configured to demodulate the first signal coupled out by the signal distribution device and output it to the quantum analyzer;

[0015] The quantum analyzer is further configured to collect and analyze the first signal demodulated by the demodulation mixer to monitor the first signal.

[0016] In an embodiment, the signal generation unit includes: an arbitrary waveform generator, an IQ mixer, and a microwave source;

[0017] The input ends of the IQ mixer are respectively connected to the arbitrary waveform generator and the microwave source; the output end of the IQ mixer is connected to the signal distribution device;

[0018] The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the signal distribution device, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer;

[0019] The arbitrary waveform generator is used to transmit a baseband signal to the IQ mixer, the microwave source outputs a local oscillator signal to the IQ mixer, and after the IQ mixer mixes the baseband signal and the local oscillator signal, it outputs the first signal to the signal distribution device;

[0020] The demodulation mixer is specifically configured to mix the first signal output by the signal distribution device with the local oscillator signal output by the microwave source, down-convert it into a signal that can be collected and analyzed by the quantum analyzer, and output it to the quantum analyzer.

[0021] In one embodiment, the signal monitoring unit includes: a signal distribution module, a combiner, and a demodulation mixer;

[0022] The combiner is arranged between the signal distribution module and the demodulation mixer;

[0023] The signal distribution module includes a plurality of signal distribution devices; the plurality of signal distribution devices are connected to the combiner;

[0024] The plurality of signal distribution devices are respectively connected to the output ends of multiple channels of the signal generation unit in a corresponding manner; each signal distribution device is used to couple out a part of the first signal of the corresponding channel;

[0025] The combiner is used to combine and output the signals coupled by the plurality of signal distribution devices;

[0026] The demodulation mixer is used to demodulate the signal output after being combined by the combiner and input it to the quantum analyzer.

[0027] In one embodiment, the signal generation unit specifically includes: an arbitrary waveform generation module, an IQ mixing module, and a microwave source;

[0028] The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the combiner, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer;

[0029] The arbitrary waveform generation module includes a plurality of arbitrary waveform generators;

[0030] The IQ mixing module includes a plurality of IQ mixers;

[0031] The multiple IQ mixers in the IQ mixing module are respectively and correspondingly connected to the multiple arbitrary waveform generators in the arbitrary waveform generation module and the output ends of multiple channels of the microwave source, so as to form multiple first signal generation channels; wherein, the input ends of each IQ mixer are respectively connected to the microwave source and the arbitrary waveform generator of the same channel; the output ends of each IQ mixer are respectively and correspondingly connected to the input ends of the signal distribution devices of the same channel of the signal distribution module;

[0032] The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the combiner and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer;

[0033] The arbitrary waveform generator is used to transmit a baseband signal to the IQ mixer, the microwave source is used to output a local oscillator signal to the IQ mixer, and the IQ mixer is used to mix the baseband signal and the local oscillator signal and output the first signal to the signal distribution device;

[0034] The microwave source is further used to output a local oscillator signal for demodulating the first signal to the demodulation mixer;

[0035] The demodulation mixer is specifically used to mix the first signal output after being combined by the combiner with the local oscillator signal for demodulating the control signal, and down-convert it into a signal that can be collected and analyzed by the quantum analyzer.

[0036] In one embodiment, the signal generation unit specifically includes: an arbitrary waveform generation module, an IQ mixing module, and a microwave source;

[0037] The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the combiner and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer;

[0038] The arbitrary waveform generation module includes an arbitrary waveform generator with multiple-channel output ends;

[0039] The IQ mixing module includes multiple IQ mixers;

[0040] The multiple IQ mixers in the IQ mixing module are respectively and correspondingly connected to the output ends of multiple channels of the arbitrary waveform generation module and the output ends of multiple channels of the microwave source, so as to form multiple first signal generation channels; wherein, the input ends of each IQ mixer are respectively connected to the output ends of the microwave source and the arbitrary waveform generator of the same channel; the output ends of each IQ mixer are respectively and correspondingly connected to the input ends of the signal distribution devices of the same channel of the signal distribution module;

[0041] The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the multiplexer, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer;

[0042] The arbitrary waveform generator is used to transmit a baseband signal to the IQ mixer, the microwave source is used to output a local oscillator signal to the IQ mixer, and the IQ mixer is used to mix the baseband signal and the local oscillator signal and output the first signal to the signal distribution device;

[0043] The microwave source is further used to output a local oscillator signal for demodulating the first signal to the demodulation mixer;

[0044] The demodulation mixer is specifically used to mix the signal output after being combined by the first multiplexer with the local oscillator signal for demodulating the first signal, and down-convert it into a signal that can be collected and analyzed by the quantum analyzer.

[0045] In one embodiment, the local oscillator signal output by the microwave source to the IQ mixer or the IQ mixer module is the same as the local oscillator signal output to the demodulation mixer.

[0046] In one embodiment, the signal distribution device is a power splitter or a directional coupler.

[0047] In one embodiment, the first signal is a read-in signal, and the signal generation unit is used to generate a read-in signal for the qubits in the quantum processing unit to read the states of the qubits.

[0048] In one embodiment, the measurement and control system is the measurement and control system in a superconducting quantum computer, and the quantum processing unit is a superconducting quantum chip.

[0049] In a second aspect, an embodiment of the present invention provides a quantum computer, including: the measurement and control system of the quantum computer as described above and a quantum processing unit;

[0050] The signal monitoring unit in the measurement and control system is connected to the quantum processing unit, and is used to couple out a part of the first signal sent by the signal generation unit in the measurement and control system, output it to the quantum analyzer for acquisition and analysis after demodulation, and output the remaining first signal to the quantum processing unit for corresponding actions on the qubits.

[0051] In one embodiment, the measurement and control system of the quantum computer further includes: a host computer;

[0052] The host computer is respectively connected to the signal sending unit and the quantum analyzer in the measurement and control system;

[0053] The host computer is used to control the signal generation unit to generate a first signal; and monitor whether the first signal is sent and whether it is abnormal according to the signals collected and analyzed by the quantum analyzer.

[0054] In a third aspect, an embodiment of the present invention provides a signal monitoring method for a quantum computer. The method uses the measurement and control system of the quantum computer as described above to monitor the first signal to be transmitted.

[0055] In one embodiment, monitoring the first signal to be transmitted includes:

[0056] The signal monitoring unit in the measurement and control system of the quantum computer partially couples out the first signal generated by the signal generation unit, demodulates it and outputs it to the quantum analyzer, and outputs the remaining first signal to the quantum processing unit;

[0057] The quantum analyzer collects and analyzes the demodulated signal output by the signal monitoring unit;

[0058] The host computer monitors whether the first signal is sent and whether it is abnormal according to the demodulated signal collected and analyzed by the quantum processing unit.

[0059] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:

[0060] In the measurement and control system of the quantum computer provided by the embodiments of the present invention, by connecting the signal monitoring unit between the signal generation unit and the quantum analyzer, a part of the first signal is coupled out by the signal monitoring unit, demodulated and then output to the quantum analyzer so that the quantum analyzer can collect and analyze the signal, thereby realizing real-time monitoring of the first signal, improving the efficiency of the first signal monitoring, and moreover, during the monitoring process, since there is no need to change the connection relationship of the measurement and control system of the quantum computer additionally, the risk of incorrect connection that may exist after the circuit is restored after inspection is also avoided.

[0061] Furthermore, the above signal monitoring unit includes a signal distribution device and a demodulation mixer. The signal distribution device can couple out a part of the first signal. The coupled-out first signal is mixed with the signal output by the microwave source through the demodulation mixer and down-converted to an intermediate frequency signal that can be collected by the quantum analyzer. Since the same-frequency microwave source is used for up-conversion and down-conversion, the signal collected by the quantum analyzer and the signal sent by the AWG are of the same frequency and the same timing, and although there are changes in amplitude, they are completely linearly corresponding, which can ensure the consistency of the monitored signal with the baseband signal originally transmitted by the AWG. Embodiments of the present invention can also monitor whether the IQ mixer and the microwave source in the high-frequency circuit are working properly.

[0062] Furthermore, the embodiment of the present invention also expands and integrates the structure of the measurement and control system through a multi-channel signal distribution module, a combiner, and a demodulation mixer. With the design of the combiner, the demand for microwave source channels is reduced from the hardware, simplifying the structure and saving hardware costs while doing so.

[0063] Other features and advantages of the present invention will be described in the following specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be realized and obtained by the structures specifically pointed out in the written specification, claims, and drawings.

[0064] The technical solution of the present invention will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0065] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0066] Figure 1 is the architecture diagram of the measurement and control system of the quantum computer in the prior art;

[0067] Figure 2 is the schematic diagram of the architecture of the measurement and control system of the quantum computer in the embodiment of the present invention;

[0068] Figure 3 is the schematic diagram of the architecture of the measurement and control system of the quantum computer in the case of a single channel for monitoring signals in the first embodiment of the present invention;

[0069] Figure 4 is the schematic diagram of the architecture of the measurement and control system of the quantum computer in the case of multiple channels for monitoring signals in the second embodiment of the present invention;

[0070] Figure 5 is the schematic diagram of the architecture for monitoring control signals in the measurement and control system of the quantum computer of the present invention;

[0071] Figure 6 is the schematic diagram of the architecture of the measurement and control system of the quantum computer in the case of a single channel for monitoring control signals of the present invention;

[0072] Figure 7 is the schematic diagram of the architecture of the measurement and control system of the quantum computer in the case of multiple channels for monitoring control signals of the present invention;

[0073] Figure 8 is the schematic diagram of the architecture for monitoring read-in signals in the measurement and control system of the quantum computer of the present invention;

[0074] Figure 9Schematic diagram of the measurement and control system of a quantum computer in the single-channel case for monitoring control signals and read-in signals according to the present invention;

[0075] Figure 10 Schematic diagram of the measurement and control system of a quantum computer in the multi-channel case for monitoring control signals and read-in signals according to the present invention;

[0076] Figure 11 Block diagram of the structure of a quantum computer provided by an embodiment of the present invention.

[0077] Description of reference numerals:

[0078] 1. Control signal generation unit; 2. Control signal monitoring unit; 3. Quantum analyzer; 4. First signal distribution device; 5. Demodulation mixer; 6. First arbitrary waveform generator; 7. First IQ mixer; 8. Microwave source; 9. First signal distribution module; 10. First combiner; 11. First arbitrary waveform generation module; 12. First IQ mixing module; 13. Second arbitrary waveform generator; 14. Second IQ mixer; 15. Second signal distribution device; 16. Demodulation mixing module; 17. Second arbitrary waveform generation module; 18. Second IQ mixing module; 19. Second combiner; 20. Host computer; 21. Switch; 22. Quantum processing unit; 23. Second signal distribution module; 24. Measurement and control system of the quantum computer; 25. Read-in signal generation unit; 26. Read-in signal monitoring unit; 27. Signal distribution device; 28. IQ mixer; 29. Arbitrary waveform generator; 33. Arbitrary waveform generation module; 34. Signal monitoring unit; 35. Signal generation unit; 36. IQ mixing module; 37. Signal distribution module; 38. Combiner. Detailed implementation manners

[0079] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0080] The inventors of the present application found that if it is suspected that the arbitrary waveform generator (AWG) does not output a control signal, or the output control signal does not meet the expectations, the solution is to change the connection line of the AWG, directly connect its output port to an external oscilloscope, and check whether the actually output waveform conforms to the waveform generated by the software theoretically.

[0081] The architecture of the existing measurement and control system of a quantum computer is referred to Figure 1As shown, the control signal is sent out by the AWG and mixed with the high-frequency signal sent out by the microwave source through the IQ mixer for mixing modulation. After up-converting to a range of, for example, 4 GHz - 8 GHz, it enters the quantum processing unit. When it is necessary to check the signal, the connection line between the AWG and the IQ mixer needs to be disconnected, and the connection line is changed to directly connect the AWG to the oscilloscope. Since the cost of an oscilloscope with a high bandwidth (above 4 GHz) is very high, generally only the signal sent out by the AWG before mixing is checked (the general frequency range is several hundred MHz). This inspection method has low efficiency, and changing the line back and forth will also bring other risks. For example, when restoring the measurement and control line, it may be connected wrongly, and repeatedly screwing the RF connector will loosen or be deformed and damaged.

[0082] Based on the above problems, the embodiment of the present invention provides an improved measurement and control system for a quantum computer to solve the above problems, realize automatic and real-time signal monitoring, improve the efficiency of signal monitoring, and avoid the problems that may occur when restoring the measurement and control line in the prior art, such as being connected wrongly, and repeatedly screwing the RF connector will loosen or be deformed and damaged.

[0083] A measurement and control system 24 for a quantum computer provided by an embodiment of the present invention is shown in reference to Figure 2 As shown, it includes: a signal generation unit 35, a signal monitoring unit 34, and a quantum analyzer 3; where:

[0084] The signal generation unit 35 is used to generate a first signal for the qubits in the quantum processing unit 22 (see Figure 3 ) of the quantum computer and perform corresponding actions on the qubits.

[0085] The input end of the signal monitoring unit 34 is connected to the signal generation unit 35, and the output end is respectively connected to the quantum processing unit 22 and the quantum analyzer 3; the signal monitoring unit 34 is used to couple out a part of the first signal generated by the signal generation unit 35, demodulate it and output it to the quantum analyzer 3, and output the remaining first signal to the qubits of the quantum processing unit 22.

[0086] The quantum analyzer 3 is used to collect and analyze the demodulated signal output by the signal monitoring unit 34.

[0087] In some embodiments, the quantum analyzer 3 can collect and perform a simple analysis on the demodulated signal, and then output it to the upper computer 20 at the upper level connected to the quantum analyzer 3 (see Figure 9 ) to perform further analysis and logical judgment, such as judging whether the first signal is sent out correctly, etc.

[0088] In some other embodiments, the quantum analyzer 3 has complex analysis and judgment functions. After collecting and analyzing the demodulated signal, it can directly further perform analysis and judgment, such as judging whether the first signal is correctly sent, etc. That is, the functions of the above-mentioned host computer 20 are integrated into one.

[0089] In this application, the "first" in the first signal does not represent the meaning of order or the like. The first signal just refers to a certain signal in the quantum computer. For example, but not limited to, the first signal refers to the control signal or the read-in signal in the measurement and control system of the quantum computer. For those skilled in the art, it can be understood that the first signal can be any suitable signal in the quantum computer, as long as it is based on the technical concept of this application, it should fall within the protection scope of this application.

[0090] When the quantum computer is, for example, a superconducting quantum computer, the control signal is a microwave signal used to control the quantum bit, such as controlling the quantum bit to rotate arbitrarily around the X and Y axes of the Bloch sphere. When the frequency of the control signal is equal to the frequency of the quantum bit, the quantum bit will be excited. The frequency range of the control signal is, for example, 4 GHz to 8 GHz. It can be understood that when the quantum computer is other suitable types of quantum computers other than the superconducting quantum computer, the control signal can also correspond to signals of other frequencies, and this application does not make any limitations in this regard.

[0091] When the quantum computer is, for example, a superconducting quantum computer, the read-in signal is a microwave signal, and the frequency of the read-in signal is equal to the frequency of the measurement resonator used to read the state of the quantum bit. According to the change of the readout signal output by the quantum processing unit 22 relative to the read-in signal, the state of the quantum bit can be determined. The frequency range of the read-in signal is, for example, 4 GHz to 8 GHz. It can be understood that when the quantum computer is other suitable types of quantum computers other than the superconducting quantum computer, the read-in signal can also correspond to signals of other frequencies, and this application does not make any limitations in this regard.

[0092] In a superconducting quantum computer, the reading of the quantum bit state is usually achieved by coupling to a measurement resonator (also called a readout resonator) of the quantum bit.

[0093] This measurement resonator is a microwave resonator, and its frequency is designed to be related to the state of the quantum bit. When wanting to read the state of the quantum bit, a microwave signal with a specific frequency will be sent to the measurement resonator - this is the so-called "read-in signal". The frequency of this signal is usually set to be equal to the frequency of the resonator.

[0094] If the qubit is in the "|0>" state, the response of the resonator will be different from that in the "|1>" state. By measuring the response of the resonator (such as the amplitude or phase change of the microwave signal), the state of the qubit can be determined.

[0095] This reading strategy is based on the "weak measurement" principle of quantum mechanics and aims to minimize the interference of the measurement process on the state of the qubit.

[0096] In the above-mentioned measurement and control system 24 of the quantum computer provided by the embodiment of the present invention, the signal monitoring unit 34 is connected between the signal generating unit 35 and the quantum analyzer 3. A part of the first signal is coupled out by the signal monitoring unit 34, demodulated and then output to the quantum analyzer 3, so that the quantum analyzer 3 can collect and analyze the signal, realizing real-time monitoring of the first signal, improving the monitoring efficiency. Moreover, during the monitoring process, since there is no need to change the connection relationship of the measurement and control system of the quantum computer additionally, the risk of incorrect connection that may exist after the circuit is restored after inspection is also avoided.

[0097] Embodiment 1:

[0098] In one embodiment, referring to Figure 3 As shown, the signal monitoring unit 34 in the measurement and control system 24 of the above-mentioned quantum computer specifically includes, for example but not limited to: a signal distribution device 27 and a demodulation mixer 5; where:

[0099] The signal distribution device 27 is connected between the signal generating unit 35 and the quantum processing unit 22;

[0100] The input ends of the demodulation mixer 5 are respectively connected to the signal distribution device 37 and the signal generating unit 35, and the output end of the demodulation mixer 5 is connected to the quantum analyzer 3;

[0101] The signal distribution device 27 is used to couple out a part of the first signal generated by the signal generating unit 35, output it to the quantum analyzer 3 for analyzing and monitoring the first signal, and output the remaining first signal to the qubits of the quantum processing unit 22 for corresponding actions;

[0102] The demodulation mixer 5 is used to demodulate the first signal coupled out by the signal distribution device 27 and then output it to the quantum analyzer 3;

[0103] The quantum analyzer 3 is further used to collect and analyze the first signal demodulated by the demodulation mixer 5 to realize monitoring of the first signal.

[0104] In specific implementation, the above-mentioned signal distribution device 27 can be implemented by, for example, a power splitter or a directional coupler, etc. However, the signal distribution device 27 can also be other suitable types of electronic devices.

[0105] The main function of the power divider is to split an input signal into multiple output signals; the structural composition of the power divider generally consists of an input end, an output end, a reflection end, a resonant cavity, and electromagnetic components. The working principle and structure of the power divider can be referred to the prior art.

[0106] The directional coupler is a passive four-port device with reciprocal ports, and one of the ports is isolated from the input port. In the ideal state, all four ports are perfectly matched and the circuit has no loss. The directional coupler can be implemented in various ways, such as microstrip line, stripline, coaxial, and waveguide, etc.

[0107] The directional coupler usually utilizes the distributed characteristics of the microwave circuit to achieve. The coupling of the signal usually occurs at a quarter wavelength or an integer multiple thereof. In these distributed couplers, the energy and fields of two adjacent partial circuits interact with each other to couple the signal from one circuit structure to another circuit structure. The specific structure and implementation principle can be referred to the prior art.

[0108] Correspondingly, continue to refer to Figure 3 As shown, the signal generating unit 35, for example but not limited to, specifically includes: an arbitrary waveform generator 33, an IQ mixer 28, and a microwave source 8; wherein:

[0109] The input ends of the IQ mixer 28 are respectively connected to the arbitrary waveform generator 33 and the microwave source 8; the output end of the IQ mixer 28 is connected to the signal distribution device 27;

[0110] The above-mentioned microwave source 8 is used to provide a microwave signal to the IQ mixer 28 and the demodulation mixer 5;

[0111] The input ends of the demodulation mixer 5 are respectively connected to the quantum processing unit 22, the output end of the signal distribution device 27, and the microwave source 8, and the output end of the demodulation mixer 5 is connected to the quantum analyzer 3;

[0112] The demodulation mixer 5 is specifically used to mix the first signal output by the signal distribution device 27 with the local oscillator signal output by the microwave source 8, down-convert it into a signal that the quantum analyzer 3 can collect and analyze, and output it to the quantum analyzer 3.

[0113] In the first embodiment, the microwave signal output by the microwave source 8 to the IQ mixer 7 is the same as the microwave signal output to the demodulation mixer 5.

[0114] In the demodulation mixer 5, the output signal is equal to the product of the input signals, and the product in the time domain corresponds to the convolution in the frequency domain. In the embodiment of the present invention, it can be realized to down-convert the high-frequency carrier into an intermediate-frequency signal.

[0115] An arbitrary waveform generator 33 (hereinafter referred to as AWG) is a signal source that can generate any desired waveform. It can generate the required waveform by using the digital data (such as control parameters) sent by the connected host computer.

[0116] The IQ mixer 28 is composed of two mixers with an internal bridge to achieve sideband suppression based on the mixers. The intermediate frequency IF consists of two paths, I and Q. The LO has an internal bridge and is composed of 2 mixers inside. When the IQ mixer is used for upconversion, it is also called a sideband suppression mixer, and a bridge is added to the IF port. By selecting the input bridge port, the upper sideband or the lower sideband of the radio frequency can be selected; by adjusting the IQ bias voltage, the LO local oscillator leakage can be adjusted; by adjusting the balance of the two paths of IQ, the sideband suppression can be adjusted. The specific structure of the IQ mixer can refer to the prior art.

[0117] In the above-mentioned measurement and control system 24 of the quantum computer provided by the embodiment of the present invention, a signal distribution device 27 is arranged between the IQ mixer 28 and the quantum processing unit 22. After the baseband signal sent by the arbitrary waveform generator 33 is mixed with the local oscillator signal sent by the microwave source 8, before entering the quantum processing unit 22, the signal distribution device 27 can couple out a part of the first signal, and a part of the first signal enters the quantum processing unit 22. The coupled-out first signal is connected to the demodulation mixer 5 and mixed with the microwave signal output by the microwave source 8, and down-converted into a signal that can be collected by the quantum analyzer 3, such as an intermediate frequency signal (with a frequency of several hundred MHz). Since the microwave source 8 provides microwave signals with the same frequency to up-convert the baseband signal output by the arbitrary waveform generator 33 and down-convert the first signal output by the IQ mixer 28, the signal collected by the quantum analyzer 3 and the signal sent by the arbitrary waveform generator 33 are of the same frequency, the same timing, and although there are changes in amplitude, they are also completely linearly corresponding. In this way, the consistency between the monitored signal and the first signal originally emitted by the arbitrary waveform generator 33 can be ensured, and the real-time monitoring of the first signal originally emitted by the arbitrary waveform generator 33 can be realized.

[0118] At the same time, because in the above-mentioned Figure 3 shown architecture, it includes a part for modulating the first signal (IQ mixer 28 and microwave source 8), and through the above-mentioned signal distribution device 27, demodulation mixer 5, quantum analyzer 3, etc., it can also check whether there are problems in the high-frequency line part (IQ mixer 28 and microwave source 8), such as whether the performance of the IQ mixer 28 is normal, whether the microwave source 8 emits normally, and whether the frequency used is correct, etc.

[0119] The process of the above-mentioned measurement and control system 24 of the quantum computer for real-time monitoring of the first signal is briefly described as follows:

[0120] The arbitrary waveform generator 33 emits the required baseband signal, which usually includes two parts: the I signal and the Q signal. The baseband signal is input into the IQ mixer 28, where it is mixed with the local oscillator signal output by the microwave source 8 to generate a high-frequency signal. After a part of the first signal is coupled out by the signal distribution device 27, the coupled first signal is connected to the demodulation mixer 5, and then mixed with the local oscillator signal output by the microwave source 8 again to be down-converted into a signal that can be collected by the quantum analyzer 3, such as an intermediate-frequency signal (with a frequency of several hundred MHz). When there is a problem with the baseband signal emitted by the arbitrary waveform generator 33, or there is a problem with the IQ mixer 28, or the microwave source 8 fails to emit microwave signals normally, etc., the host computer 20 connected to the quantum analyzer 3 can know in real time.

[0121] Embodiment 2:

[0122] In the second embodiment of the present invention, for the multi-qubit measurement and control circuit, it is necessary to expand and integrate the structure of the measurement and control system 24 in the first embodiment.

[0123] Correspondingly, referring to Figure 4 As shown, the above signal monitoring unit 34 includes: a signal distribution module 37, a combiner 38, and a demodulation mixer 5; where:

[0124] The combiner 38 is arranged between the signal distribution module 37 and the demodulation mixer 5;

[0125] The signal distribution module 37 includes a plurality of signal distribution devices 27; the plurality of signal distribution devices 27 are connected to the combiner 38;

[0126] The plurality of signal distribution devices 27 are respectively connected to the multi-channel output ends of the signal generation unit 35; each signal distribution device 27 is used to couple out a part of the first signal of the corresponding channel and output the remaining first signal to the quantum processing unit 22;

[0127] The combiner 38 is used to combine and output the first signals coupled by the plurality of signal distribution devices 27;

[0128] The demodulation mixer 5 is used to demodulate the first signal combined and output by the combiner 38 and then input it to the quantum analyzer 3.

[0129] Similar to the first embodiment, in specific implementation, the above signal distribution device 27 can be implemented by, for example, a power splitter or a directional coupler, etc.

[0130] The above signal generation unit 35, referring to Figure 4 As shown, specifically includes: an arbitrary waveform generation module 33, an IQ mixing module 36, and a microwave source 8;

[0131] The input ends of the demodulation mixer 5 are respectively connected to the quantum processing unit 22, the output end of the multiplexer 38, and the microwave source 8, and the output end of the demodulation mixer 32 is connected to the quantum analyzer 3;

[0132] The arbitrary waveform generation module 33 includes a plurality of arbitrary waveform generators 29; alternatively, the arbitrary waveform generation module 33 includes an arbitrary waveform generator 29 with multi-channel output ends;

[0133] The IQ mixing module 36 includes a plurality of IQ mixers 28;

[0134] The plurality of IQ mixers 28 in the IQ mixing module 36 are respectively and correspondingly connected to the plurality of arbitrary waveform generators 33 in the arbitrary waveform generation module 33 and the multi-channel output ends of the microwave source 8 to form a plurality of control signal generation channels (corresponding to the case where the arbitrary waveform generation module 33 includes a plurality of arbitrary waveform generators 29); wherein, the input ends of each IQ mixer 28 are respectively connected to the output ends of the microwave source 8 and the arbitrary waveform generator 29 in the same channel; the output ends of each IQ mixer 28 are respectively and correspondingly connected to the input ends of the signal distribution devices 27 in the same channel of the signal distribution module 27;

[0135] Alternatively, the connection manner of the plurality of IQ mixers 28 in the above IQ mixing module 36 with the arbitrary waveform generation module 33 and the microwave source 8 may also be: the plurality of IQ mixers 28 in the IQ mixing module 36 are respectively and correspondingly connected to the multi-channel output ends of the arbitrary waveform generation module 33 and the multi-channel output ends of the microwave source 8 to form a plurality of first signal generation channels (corresponding to the case where the arbitrary waveform generation module 33 includes an arbitrary waveform generator 29 with multi-channel output ends).

[0136] The microwave source 8 is used to output a local oscillator signal for demodulation to the demodulation mixer 32;

[0137] In the case where the multiplexer 38 multiplexes multiple first signals, the microwave source 8 outputs a local oscillator signal for demodulation, that is, each first signal uses the same local oscillator signal for demodulation.

[0138] The demodulation mixer 5 is specifically configured to mix the signal output after being combined by the multiplexer 38 with the local oscillator signal of the first signal for demodulation output by the microwave source 8 and down-convert it into a signal that can be collected and analyzed by the quantum analyzer.

[0139] Figure 4In the shown system architecture, since multiple transmission channels for the first signals are required, correspondingly, any of the above-mentioned arbitrary waveform generation modules 33 may include multiple arbitrary waveform generators 29, with each arbitrary waveform generator 29 corresponding to one channel; or the arbitrary waveform generation module 33 itself includes an arbitrary waveform generator 29 with multi-channel outputs, and the multiple output channels of this arbitrary waveform generator 29 correspond to the transmission channels for the multiple first signals.

[0140] On the same channel, the output end of an arbitrary waveform generator 29 is connected to the input end of an IQ mixer 28, and the other input end of this IQ mixer 28 is connected to the output end of a microwave source 8.

[0141] On the same channel, the output end of this IQ mixer 28 is connected to the input end of a signal distribution device 27.

[0142] In this way, the combiner 38 will have multi-channel inputs. The combiner 38 combines the multi-channel signals and then outputs them. In this way, each channel uses a corresponding signal distribution device 27 (such as a directional coupler or a power splitter) to combine all the first signals coupled out by the multi-channel signal distribution devices 27 through the combiner 38, and then uses the same microwave source 8 for down-conversion uniformly to obtain signals that the quantum analyzer 3 can collect and analyze. This architecture not only realizes the expansion and integration of multi-qubit measurement and control circuits, but also reduces the demand for the channels of the microwave source 8 in terms of hardware. While simplifying the structure, it saves hardware costs.

[0143] Figure 4 The shown system architecture has similar characteristics and advantages to, for example Figure 3 the single-channel system architecture shown, such as the ability to monitor the AWG transmission signals of multiple channels, and the ability to monitor whether there are problems in the high-frequency circuits of multiple channels, etc.

[0144] The process of the measurement and control system of the above-mentioned quantum computer for real-time monitoring of the first signals is briefly described as follows:

[0145] The arbitrary waveform generator 29 in the arbitrary waveform generation module 33 transmits the required multi-channel baseband signals (IQ signals), which are respectively input to the IQ mixing module 36. In the IQ mixing module 36, each IQ mixer 28 mixes them with the local oscillator signal (also called: microwave signal) output by the microwave source 8 to generate high-frequency signals. Then, after each signal distribution device 27 in the signal distribution module 37 couples out a part of the first signal respectively, they are combined into one first signal. The first signal obtained after combination is connected to the demodulation mixer 5, and then mixed with the local oscillator signal output by the microwave source 8 to be down-converted into a signal that can be collected by the quantum analyzer 3, such as an intermediate frequency signal (with a frequency of several hundred MHz). When there is a problem with the baseband signal transmitted by the arbitrary waveform generation module 33, or there is a problem with the IQ mixing module 36, or the microwave source 8 fails to transmit the microwave signal normally, etc., the host computer 20 connected to the quantum analyzer 3 can know in real time. In the above-mentioned second embodiment, the microwave signal output by the microwave source 8 to the IQ mixing module 36 is the same as the microwave signal output to the demodulation mixer 5.

[0146] In the following, three cases of monitoring the control signal, monitoring the read-in signal, and monitoring the control signal and the read-in signal in the measurement and control system 24 of the quantum computer of the present invention will be taken as examples for description respectively.

[0147] Embodiment of the single-channel case of monitoring the control signal:

[0148] A measurement and control system 24 of a quantum computer provided by an embodiment of the present invention, referring to Figure 5 as shown, includes: a control signal generation unit 1, a control signal monitoring unit 2, and a quantum analyzer 3; where:

[0149] The control signal generation unit 1 is used to generate a control signal for manipulating the quantum bits in the quantum processing unit 22 of the quantum computer.

[0150] The input end of the control signal monitoring unit 2 is connected to the control signal generation unit 1, and the output end is respectively connected to the quantum processing unit 22 and the quantum analyzer 3; the control signal monitoring unit 2 is used to couple out a part of the control signal generated by the control signal generation unit 1, demodulate it and output it to the quantum analyzer 3, and output the remaining control signals to the quantum processing unit 22 for controlling the quantum bits.

[0151] The quantum analyzer 3 is used to collect and analyze the demodulated signal output by the control signal monitoring unit 2.

[0152] In some embodiments, the quantum analyzer 3 can collect and perform simple analysis on the demodulated signal, and then output it to the host computer 20 at the upper level connected to the quantum analyzer 3 for further analysis and logical judgment, such as judging whether the control signal is correctly sent, whether the order of the control signal and the read-in signal is correct, and so on.

[0153] In some other embodiments, the quantum analyzer 3 has complex analysis and judgment functions. After collecting and analyzing the demodulated signal, it can directly perform further analysis and judgment, such as judging whether the control signal is correctly sent, whether the order of the control signal and the read-in signal is correct, and so on. That is, the functions of the above-mentioned host computer 20 are integrated into one.

[0154] When the quantum computer is, for example, a superconducting quantum computer, the control signal is a microwave signal used to control qubits, such as controlling the qubits to rotate arbitrarily around the X and Y axes of the Bloch sphere. When the frequency of the control signal is equal to the frequency of the qubit, the qubit will be excited. The frequency range of the control signal is, for example, from 4 GHz to 8 GHz. It can be understood that when the quantum computer is other suitable types of quantum computers other than superconducting quantum computers, the control signal can also correspond to signals of other frequencies, and the present application does not limit this.

[0155] In the measurement and control system 24 of the quantum computer provided by the embodiments of the present invention, the control signal monitoring unit 2 is connected between the control signal generating unit 1 and the quantum analyzer 3. A part of the control signal is coupled out through the control signal monitoring unit 2, demodulated and then output to the quantum analyzer 3, so that the quantum analyzer 3 can collect and analyze the signal, realizing real-time monitoring of the control signal, improving the monitoring efficiency, and moreover, during the monitoring process, since there is no need to additionally change the connection relationship of the measurement and control system 24 of the quantum computer, the risk of incorrect connection that may exist when restoring the circuit after inspection is also avoided.

[0156] In one embodiment, referring to Figure 6 as shown, the control signal monitoring unit 2 in the measurement and control system 24 of the above-mentioned quantum computer, for example but not limited to, specifically includes: a first signal distribution device 4 and a demodulation mixer 5; where:

[0157] The first signal distribution device 4 is connected between the control signal generating unit 1 and the quantum processing unit 22;

[0158] The input ends of the demodulation mixer 5 are respectively connected to the first signal distribution device 4 and the control signal generating unit 1, and the output end of the demodulation mixer 5 is connected to the quantum analyzer 3;

[0159] The first signal distribution device 4 is configured to couple out a part of the control signal generated by the control signal generating unit 1, output it to the quantum analyzer 3 for analyzing and monitoring the control signal, and output the remaining control signal to the qubits of the quantum processing unit 22 for control operations;

[0160] The demodulation mixer 5 is configured to demodulate the control signal coupled out by the first signal distribution device 4 and then output it to the quantum analyzer 3;

[0161] The quantum analyzer 3 is further configured to collect and analyze the control signal demodulated by the demodulation mixer 5 to monitor the control signal.

[0162] In specific implementation, the above first signal distribution device 4 can be implemented by, for example, a power splitter or a directional coupler. However, the first signal distribution device 4 can also be other suitable types of electronic devices.

[0163] Correspondingly, continuing to refer to Figure 6 As shown, the control signal generating unit 1 specifically includes, for example but not limited to: a first arbitrary waveform generator 6, a first IQ mixer 7, and a microwave source 8; where:

[0164] The input terminals of the first IQ mixer 7 are respectively connected to the first arbitrary waveform generator 6 and the microwave source 8; the output terminal of the first IQ mixer 7 is connected to the first signal distribution device 4;

[0165] The above microwave source 8 is configured to provide a microwave signal to the first IQ mixer 7 and the demodulation mixer 5;

[0166] The input terminals of the demodulation mixer 5 are respectively connected to the quantum processing unit 22, the output terminal of the first signal distribution device 4, and the microwave source 8, and the output terminal of the demodulation mixer 5 is connected to the quantum analyzer 3;

[0167] The demodulation mixer 5 is specifically configured to mix the control signal output by the first signal distribution device 4 with the local oscillator signal (also referred to as: microwave signal) output by the microwave source 8, down-convert it into a signal that the quantum analyzer 3 can collect and analyze, and output it to the quantum analyzer 3.

[0168] In the first embodiment, the microwave signal (local oscillator signal) output by the microwave source 8 to the first IQ mixer 7 is the same as the microwave signal (local oscillator signal) output to the demodulation mixer 5.

[0169] In the demodulation mixer 5, the output signal is equal to the product of the input signals, and the product in the time domain corresponds to the convolution in the frequency domain. In the embodiments of the present invention, it can be realized to down-convert the high-frequency carrier into an intermediate-frequency signal.

[0170] An arbitrary waveform generator (hereinafter referred to as AWG) is a signal source that can generate any desired waveform. It can generate the required waveform by using the digital data (such as control parameters) sent by the connected host computer.

[0171] The IQ mixer consists of two mixers with an internal bridge to achieve sideband suppression based on the mixers. The intermediate frequency IF consists of two paths, I and Q. The LO has an internal bridge and is composed of 2 mixers inside. When the IQ mixer is used as an upconverter, it is also called a sideband suppression mixer, and a bridge is added to the IF port. By selecting the input bridge port, the upper sideband or lower sideband of the radio frequency can be selected; by adjusting the IQ bias voltage, the LO local oscillator leakage can be adjusted; by adjusting the balance of the two paths of IQ, the sideband suppression can be adjusted. The specific structure of the IQ mixer can refer to the prior art.

[0172] In the measurement and control system 24 of the quantum computer provided in the embodiment of the present invention, a first signal distribution device 4 is provided between the first IQ mixer 7 and the quantum processing unit 22. After the baseband signal sent by the first arbitrary waveform generator 6 is mixed with the local oscillator signal output by the microwave source 8, before entering the quantum processing unit 22, the first signal distribution device 4 can couple out a part of the control signal, and a part of the control signal enters the quantum processing unit 22. The coupled control signal is connected to the demodulation mixer 5 and mixed with the microwave signal output by the microwave source 8 to be downconverted into a signal that can be collected by the quantum analyzer 3, such as an intermediate frequency signal (with a frequency of several hundred MHz). Since the microwave source 8 provides microwave signals of the same frequency to upconvert the baseband signal output by the first arbitrary waveform generator 6 and downconvert the control signal output by the first IQ mixer 7, the signal collected by the quantum analyzer 3 and the signal sent by the first arbitrary waveform generator 6 are of the same frequency, the same timing, and although there are changes in amplitude, they are also completely linearly corresponding. In this way, the consistency between the monitored signal and the baseband signal originally emitted by the first arbitrary waveform generator 6 can be ensured, and the real-time monitoring of the signal originally emitted by the first arbitrary waveform generator 6 can be realized.

[0173] At the same time, because in the Figure 6 architecture shown above, it includes a part for modulating the control signal (the first IQ mixer 7 and the microwave source 8), and problems in the high-frequency circuit part (the first IQ mixer 7 and the microwave source 8) can also be detected through the above-mentioned first signal distribution device 4, demodulation mixer 5, quantum analyzer 3, etc., such as whether the performance of the first IQ mixer 7 is normal, whether the microwave source 8 emits signals normally, and whether the frequency used is correct, etc.

[0174] The process of the above-mentioned quantum measurement and control system for real-time signal monitoring is briefly described as follows:

[0175] The first arbitrary waveform generator 6 transmits the required baseband signals (I-channel signal and Q-channel signal), which are input to the first IQ mixer 7. In the first IQ mixer 7, they are mixed with the microwave source 8 to generate a high-frequency signal. After a part of the control signal is coupled out by the first signal distribution device 4, the coupled control signal is connected to the demodulation mixer 5, and then mixed with the microwave signal output by the microwave source 8 to be down-converted into a signal that can be collected by the quantum analyzer 3, such as an intermediate-frequency signal (with a frequency of several hundred MHz). When there is a problem with the baseband signal transmitted by the first arbitrary waveform generator 6, or a problem with the first IQ mixer 7, or the microwave source 8 fails to transmit signals normally, etc., the host computer 20 connected to the quantum analyzer 3 can know in real time.

[0176] Embodiment of the multi-channel situation for monitoring the control signal:

[0177] In the embodiment of the present invention, for the multi-qubit measurement and control circuit, it is necessary to expand and integrate the structure of the measurement and control system 24 in the above single-channel embodiment.

[0178] Correspondingly, referring to Figure 7 As shown, the above control signal monitoring unit 2 includes: a first signal distribution module 9, a first combiner 10, and a demodulation mixer 5; where:

[0179] The first combiner 10 is arranged between the first signal distribution module 9 and the demodulation mixer 5;

[0180] The first signal distribution module 9 includes a plurality of first signal distribution devices 4; the plurality of first signal distribution devices 4 are connected to the first combiner 10;

[0181] The plurality of first signal distribution devices 4 are respectively connected to the multi-channel output ends of the control signal generating unit 1; each first signal distribution device 4 is used to couple out a part of the control signal of the corresponding channel and output the remaining control signal to the quantum processing unit 22;

[0182] The first combiner 10 is used to combine and output the control signals coupled by the plurality of first signal distribution devices 4;

[0183] The demodulation mixer 5 is used to demodulate the control signal combined and output by the first combiner 10 and input it to the quantum analyzer 3.

[0184] In specific implementation, the first signal distribution device 4 can be implemented by, for example, a power divider or a directional coupler, etc.

[0185] The above control signal generating unit 1, referring to Figure 4 As shown, specifically includes: a first arbitrary waveform generating module 11, a first IQ mixing module 12, and a microwave source 8;

[0186] The input ends of the demodulation mixer 5 are respectively connected to the quantum processing unit 22, the output end of the first multiplexer 10, and the microwave source 8, and the output end of the demodulation mixer is connected to the quantum analyzer 3;

[0187] The first arbitrary waveform generation module 11 includes a plurality of first arbitrary waveform generators 6; alternatively, the first arbitrary waveform generation module 11 includes a first arbitrary waveform generator 6 having a multi-channel output end;

[0188] The first IQ mixing module 12 includes a plurality of first IQ mixers 7;

[0189] The plurality of first IQ mixers 7 in the first IQ mixing module 12 are respectively and correspondingly connected to the plurality of first arbitrary waveform generators 6 in the first arbitrary waveform generation module 11 and the multi-channel output end of the microwave source 8 to form a plurality of control signal generation channels (corresponding to the case where the first arbitrary waveform generation module 11 includes a plurality of first arbitrary waveform generators 6); wherein, the input ends of each first IQ mixer 7 are respectively connected to the output ends of the microwave source 8 and the first arbitrary waveform generator 6 in the same channel; the output ends of each first IQ mixer 7 are respectively and correspondingly connected to the input ends of the first signal distribution devices 4 in the same channel of the first signal distribution module 9;

[0190] Alternatively, the connection manner of the plurality of first IQ mixers 7 in the first IQ mixing module 12 with the first arbitrary waveform generation module 11 and the microwave source 8 may also be: the plurality of first IQ mixers 7 in the first IQ mixing module 12 are respectively and correspondingly connected to the multi-channel output end of the first arbitrary waveform generation module 11 and the multi-channel output end of the microwave source 8 to form a plurality of control signal generation channels (corresponding to the case where the first arbitrary waveform generation module 11 includes a first arbitrary waveform generator 6 having a multi-channel output end).

[0191] The microwave source 8 is used to output a local oscillator signal for demodulation to the demodulation mixer 5;

[0192] In the case of multiplexing a plurality of control signals using the first multiplexer 10, the microwave source 8 outputs a local oscillator signal for demodulation, that is, each control signal is demodulated using the same local oscillator signal.

[0193] The demodulation mixer 5 is specifically configured to mix the control signal output after being combined by the first multiplexer 10 with the local oscillator signal for demodulating the control signal output by the microwave source 8 and down-convert it into a signal that can be collected and analyzed by the quantum analyzer.

[0194] Figure 4In the shown system architecture, since multiple transmission channels for control signals are required, correspondingly, the above-mentioned first arbitrary waveform generation module 11 may include multiple first arbitrary waveform generators 6, and each first arbitrary waveform generator 6 corresponds to one channel; or the first arbitrary waveform generation module 11 itself includes a first arbitrary waveform generator 6 with multi-channel outputs, and the multiple output channels of this first arbitrary waveform generator 6 correspond to the transmission channels of multiple control signals.

[0195] On the same channel, the output end of a first arbitrary waveform generator 6 is connected to the input end of a first IQ mixer 7, and the other input end of this first IQ mixer 7 is connected to the output end of a microwave source 8.

[0196] On the same channel, the output end of this first IQ mixer 7 is connected to the input end of a first signal distribution device 4.

[0197] In this way, the first combiner 10 will have multi-channel inputs. The first combiner 10 combines the multi-channel control signals and then outputs them. In this way, each channel uses a corresponding first signal distribution device 4 (such as a directional coupler or a power splitter) to combine all the control signals coupled out by the multi-channel first signal distribution devices 4 through the first combiner 10, and then uses the same microwave source 8 for down-conversion uniformly to obtain signals that the quantum analyzer 3 can collect and analyze. This architecture not only realizes the expansion and integration of multi-qubit measurement and control circuits, but also reduces the requirement for the channels of the microwave source 8 in terms of hardware, simplifies the structure, and saves hardware costs while doing so.

[0198] Figure 4 The shown system architecture has similar characteristics and advantages to, for example Figure 6 the single-channel system architecture shown, such as the ability to monitor the AWG transmission signals of multiple paths, and the ability to monitor whether there are problems in the high-frequency lines of multiple paths, etc.

[0199] The process of the above-mentioned measurement and control system 24 of the quantum computer for real-time monitoring of control signals is briefly described as follows:

[0200] The first arbitrary waveform generator 6 in the first arbitrary waveform generation module 11 emits the required multi-channel baseband signals (I-channel signal and Q-channel signal), which are respectively input into the first IQ mixing module 12. In the first IQ mixing module 12, each first IQ mixer 7 mixes it with the microwave signal output by the microwave source 8 to generate a high-frequency signal. Then, after each first signal distribution device 4 in the first signal distribution module 9 respectively couples out a part of the control signal, they are combined to form a control signal. The combined control signal is connected to the demodulation mixer 5, and then mixed with the microwave signal output by the microwave source 8 to be down-converted into a signal that can be collected by the quantum analyzer 3, such as an intermediate frequency signal (with a frequency of several hundred MHz). When there is a problem with the signal emitted by the first arbitrary waveform generation module 11, or there is a problem with the first IQ mixing module 12, or the microwave source 8 fails to emit a signal normally, etc., the host computer 20 connected to the quantum analyzer 3 can know in real time. In the above-mentioned second embodiment, the microwave signal output by the microwave source 8 to the first IQ mixing module 12 is the same as the microwave signal output to the demodulation mixer 5.

[0201] Both the above-mentioned first embodiment and the second embodiment illustrate the improvement of the channel for the control signal, which involves the monitoring of the control signal. In the embodiment of the present invention, in addition to the above improvement of the channel for the control signal, optionally, the channel for the read-in signal can also be improved in the same or similar way.

[0202] Embodiment for monitoring the read-in signal:

[0203] Please refer to Figure 8 , Figure 8 which is a schematic diagram of the framework of an embodiment for the measurement and control system 24 of the quantum computer of the present application to monitor the read-in signal. The measurement and control system 24 of the quantum computer includes: a read-in signal generation unit 25, a read-in signal monitoring unit 26, and a quantum analyzer 3. The input end of the read-in signal monitoring unit 26 is connected to the read-in signal generation unit 25, and the output end is respectively connected to the quantum analyzer 3 and the quantum processing unit 22.

[0204] The read-in signal generation unit 25 is used to generate a read-in signal for the quantum processing unit 22 of the quantum computer to read the state of the quantum bits in the quantum processing unit 22;

[0205] The read-in signal monitoring unit 26 is used to partially couple out a part of the read-in signal generated by the read-in signal generation unit 25, demodulate it and output it to the quantum analyzer 3, and output the remaining read-in signal to the quantum processing unit 22;

[0206] The quantum analyzer 3 is used to collect and analyze the demodulated signal output by the read-out signal monitoring unit 26 to realize the monitoring of the read-in signal.

[0207] The quantum analyzer 3 is also used to collect and analyze the readout signal output by the quantum processing unit 22 to read the state of the qubit.

[0208] When the quantum computer is a superconducting quantum computer, for example, the read-in signal is a microwave signal, and the frequency of the read-in signal is equal to the frequency of the measurement resonator for reading the state of the qubit. The state of the qubit can be determined according to the change of the readout signal output by the quantum processing unit 22 relative to the read-in signal. The frequency range of the read-in signal is, for example, 4 GHz to 8 GHz. It can be understood that when the quantum computer is other suitable types of quantum computers other than the superconducting quantum computer, the read-in signal can also correspond to signals of other frequencies, and the present application does not limit this.

[0209] In the measurement and control system 24 of the quantum computer provided by the embodiment of the present invention, the read-in signal monitoring unit 26 is connected between the read-in signal generating unit 25 and the quantum analyzer 3. A part of the read-in signal is coupled out by the read-in signal monitoring unit 26, and after demodulation, it is output to the quantum analyzer 3 so that the quantum analyzer 3 can perform signal collection and analysis, realizing real-time monitoring of the read-in signal, improving the monitoring efficiency, and moreover, during the monitoring process, since there is no need to change the connection relationship of the measurement and control system 24 of the quantum computer additionally, the risk of incorrect connection that may exist after restoring the circuit after inspection is also avoided.

[0210] For the sake of clarity and conciseness, the separate descriptions of the single-channel embodiment and the multi-channel embodiment for monitoring the read-in signal are omitted here, and the relevant descriptions of the above-mentioned Embodiment 1 and Embodiment 2 can be equally referred to. Here, the read-in signal is an embodiment of the first signal. In addition, the relevant descriptions of simultaneously monitoring the control signal and the read-in signal below can also be referred to, where the relevant hardware, signal flow, etc. descriptions of the read-in signal are also applicable to the single-channel embodiment and the multi-channel embodiment for monitoring this read-in signal. This can be understood by those skilled in the art.

[0211] Embodiment of the single-channel case of monitoring the control signal and the read-in signal:

[0212] The structure of a measurement and control system of a quantum computer that improves both the control signal path and the read-in signal path can be seen Figure 9As shown in the figure. For the sake of convenience in description, in the above embodiments, for the components in the control signal path, a prefix of "first" is used to name them. For example, the first signal distribution device, the first arbitrary waveform generator, the first IQ mixer, etc. In the following embodiments of the present invention, the components of the control signal path are still the same as those in the above embodiments, while for the components of the read-in signal path, a prefix of "second" is used to name them. The above "first" and "second" are only used to distinguish different components.

[0213] For the components that are not distinguished by "first" and "second", it means they are the components shared by the control signal path and the read-in signal path.

[0214] For the structure and function of the control signal channel in this embodiment (the structure and function of the first arbitrary waveform generator 6, the first IQ mixer 7, the first signal distribution device 4, the demodulation and mixing module 16, etc. in the solution for monitoring the control signal), reference can be made to the description of the foregoing embodiments and will not be elaborated here.

[0215] Refer to Figure 9 As shown in the figure, on the basis of the relevant structures of the control signal path and the relevant structures of the read-in signal path in the above embodiments, the measurement and control system 24 of the quantum computer will be further described. The read-in signal generation unit 25 includes: a second arbitrary waveform generator 13, a second IQ mixer 14, and a microwave source 8; the read-in signal generation unit 25 and the control signal generation unit 1 share the same microwave source 8; sharing the same microwave source 8 can save hardware costs. In some possible embodiments, the read-in signal generation unit 25 and the control signal generation unit 1 may not share the same microwave source 8, but use their respective microwave sources 8, which is not limited in the embodiments of the present invention.

[0216] The input end of the read-in signal monitoring unit 26 is connected to the read-in signal generation unit 25, and the output end of the read-in signal monitoring unit 26 is respectively connected to the quantum processing unit 22 and the quantum analyzer 3; the read-in signal monitoring unit 26 is used to couple out a part of the read-in signal generated by the read-in signal generation unit 25, demodulate it and output it to the quantum analyzer 3, and output the remaining read-in signals to the quantum processing unit 22.

[0217] Specifically, the read-in signal monitoring unit includes: a second signal distribution device 15 and a demodulation and mixing module 16;

[0218] Since a single solution call mixer can usually only process one signal (control signal or read signal), the above-mentioned read signal monitoring unit 26 and control signal monitoring unit 2 respectively use corresponding solution call mixers for demodulation. In specific implementation, from a hardware perspective, the solution call mixer 5 corresponding to the read signal monitoring unit 26 and the solution call mixer 5 corresponding to the control signal monitoring unit 2 can be integrated, for example, on the same module, that is, the above-mentioned solution call mixing module 16. Of course, the solution call mixers included in the solution call mixing module 16 may not be integrated either.

[0219] A second signal distribution device 15 for coupling out a part of the read signal generated by the read signal generation unit 25;

[0220] The solution call mixing module 16 is further configured to demodulate the read signal coupled out by the second signal distribution device 15 and output it to the quantum analyzer 3;

[0221] The quantum analyzer 3 is further configured to collect and analyze the read signal demodulated by the solution call mixing module 16 to monitor the read signal and / or monitor the relative order of the control signal and the read signal.

[0222] Similar to the path of the control signal, the above-mentioned microwave source 8 is used to provide a microwave signal to the second IQ mixer 14 and the solution call mixing module 16.

[0223] Refer to Figure 9 As shown, the input ends of the solution call mixing module 16 are respectively connected to the quantum processing unit 22, the output end of the first signal distribution device 4, the output end of the second signal distribution device 14, and the microwave source 8, and the output end of the solution call mixing module 16 is connected to the quantum analyzer 3.

[0224] The solution call mixer in the solution call mixing module 16 is specifically configured to mix the read signal coupled out by the second signal distribution device 15 with the local oscillator signal output by the microwave source 8, down-convert it into a signal that the quantum analyzer 3 can collect and analyze, and output it to the quantum analyzer 3.

[0225] In this embodiment, the microwave signal (i.e., the local oscillator signal) output by the microwave source 8 to the second IQ mixer 14 is the same as the microwave signal (i.e., the local oscillator signal) output to the solution call mixing module 16.

[0226] In specific implementation, the above-mentioned second signal distribution device 15 can be implemented, for example, by a power splitter or a directional coupler, etc. However, the second signal distribution device 15 can also be other suitable types of electronic devices. Regarding the structure and corresponding functions of the power splitter and the directional coupler, reference can be made to the description of the foregoing Embodiment 1.

[0227] The quantum analyzer 3 can collect and simply analyze the demodulated input signal, and then output it to the host computer 20 at the upper level connected to the quantum analyzer 3 for further analysis and logical judgment, such as judging whether the input signal is correct, whether the order of the control signal and the input signal is correct, and so on.

[0228] In some other embodiments, the quantum analyzer 3 itself has complex analysis and judgment functions. After collecting and analyzing the demodulated input signal, it can directly further analyze and judge, such as judging whether the input signal is correct, whether the order of the control signal and the input signal is correct, and so on.

[0229] It should be noted that if only a single path is involved, such as only the improvement of the control signal path, a single demodulation mixer 5 can be used. However, if both the control signal path and the input signal path are involved, the demodulation mixer module 16 includes multiple demodulation mixers 5 to respectively achieve the demodulation of the control signal and the input signal.

[0230] In Figure 9 this case, the host computer 20 interacts with the microwave source 8, the first arbitrary waveform generator 6, the second arbitrary waveform generator 13, and the quantum analyzer 3 through, for example, a switch 21. In some embodiments, the host computer 20 can also directly interact with these devices without necessarily passing through network devices such as switches, or it is also possible to interact with these devices through other suitable devices such as a USB interface.

[0231] In the measurement and control system 24 of the quantum computer provided in the embodiment of the present invention, a second signal distribution device 15 is provided between the second IQ mixer 14 and the quantum processing unit 22. After the read-in signal sent by the second arbitrary waveform generator 13 is mixed with the microwave signal output by the microwave source 8 and before entering the quantum processing unit 22, the second signal distribution device 15 can couple out a part of the read-in signal, and a part of the read-in signal enters the quantum processing unit 22. The coupled-out read-in signal is connected to the demodulation mixing module 16 and mixed with the microwave signal output by the microwave source 8, and is down-converted into a signal that can be collected by the quantum analyzer 3, such as an intermediate frequency signal (with a frequency of several hundred MHz). Since the microwave source 8 provides microwave signals of the same frequency to up-convert the read-in signal output by the second arbitrary waveform generator 13 and to down-convert the read-in signal output by the second IQ mixer 14, the signal collected by the quantum analyzer 3 and the signal sent by the second arbitrary waveform generator 13 are of the same frequency, the same timing sequence, and although there are changes in amplitude, they are also completely linearly corresponding. In this way, the consistency between the monitored read-in signal and the baseband signal originally emitted by the second arbitrary waveform generator 13 can be ensured, the real-time monitoring of the signal originally emitted by the second arbitrary waveform generator 13 is realized, the monitoring efficiency is improved, and moreover, during the monitoring process, since there is no need to additionally change the connection relationship of the measurement and control system of the quantum computer, the risk of incorrect connection that may exist after the circuit is restored after inspection is also avoided.

[0232] Embodiment of the multi-channel situation for monitoring the control signal and the read-in signal:

[0233] For the structure and function of the channel of the control signal in this embodiment (the structure and function of the first arbitrary waveform generation module 11, the first IQ mixing module 12, the first signal distribution module 9, the demodulation mixing module 16, etc. in the solution for monitoring the control signal), reference can be made to the descriptions of the foregoing embodiments, and details will not be repeated here.

[0234] Similar to the second embodiment and other embodiments above, for the multi-qubit measurement and control circuit, it is necessary to expand and integrate the structure of the above embodiment, and improve both the control signal channel and the read-in signal channel. Refer to Figure 10 As shown, the measurement and control system 24 of the quantum computer will be further described in relation to the relevant structures of the control signal path and the relevant structures of the read-in signal path in the above embodiment.

[0235] The read-in signal monitoring unit 26 includes: a second signal distribution module 23, a second combiner 19, and a demodulation mixing module 16;

[0236] The second combiner 19 is arranged between the second signal distribution module 23 and the demodulation mixing module 16;

[0237] The second signal distribution module 23 includes a plurality of second signal distribution devices 15; the plurality of second signal distribution devices 15 are connected to the second combiner 19;

[0238] The plurality of second signal distribution devices 15 are respectively connected to the multi-channel output ends of the read-in signal generating unit 25 in a corresponding manner; each of the second signal distribution devices 15 is used to couple out a part of the read-in signal of the corresponding channel and output the remaining read-in signal to the quantum processing unit 22;

[0239] The second combiner 19 is used to combine and output the signals coupled by the plurality of second signal distribution devices 15;

[0240] The demodulation mixer 5 is used to demodulate the signal output after being combined by the second combiner 19 and input it to the quantum analyzer 3.

[0241] Specifically, the read-in signal generating unit 25, for example, includes: a second arbitrary waveform generating module 17, a second IQ mixing module 18, and a microwave source 8;

[0242] The read-in signal generating unit 25 and the control signal generating unit 1 share the same microwave source 8;

[0243] Similar to the foregoing embodiment, the read-in signal generating unit 25 and the control signal generating unit 1 may not necessarily share the same microwave source 8.

[0244] The input ends of the demodulation mixing module 16 are respectively connected to the quantum processing unit 22, the output end of the second combiner 19, and the microwave source 8, and the output end of the demodulation mixing module 16 is connected to the quantum analyzer 3;

[0245] The second arbitrary waveform generating module 17 includes a plurality of second arbitrary waveform generators 13;

[0246] The second IQ mixing module 18 includes a plurality of second IQ mixers 14;

[0247] The plurality of second IQ mixers 14 in the second IQ mixing module 18 are respectively connected to the plurality of second arbitrary waveform generators 13 in the second arbitrary waveform generating module 17 and the multi-channel output ends of the microwave source 8 in a corresponding manner to form a plurality of read-in signal generating channels; wherein, the input ends of each second IQ mixer 14 are respectively connected to the output end of the microwave source 8 and the second arbitrary waveform generator 13 of the same channel; the output ends of each second IQ mixer 14 are respectively connected to the input ends of the second signal distribution devices 15 of the same channel of the second signal distribution module 23 in a corresponding manner;

[0248] The microwave source 8 is used to output a local oscillator signal for demodulating the read-in signal to the demodulation mixing module;

[0249] Although the read-in signals involve multiple channels, when demodulating, the mixing module uses the same local oscillator signal for demodulating the read-in signals of multiple channels.

[0250] The demodulating mixing module 16 is specifically configured to mix the signal output after being combined by the second combiner 19 with a local oscillator signal for demodulating the read-in signal, and down-convert it into a signal that can be collected and analyzed by the quantum analyzer.

[0251] The quantum analyzer 3 is further configured to collect and analyze the read-in signal demodulated by the demodulating mixing module 16, so as to monitor the read-in signal and / or monitor the relative order of the control signal and the read-in signal.

[0252] The second arbitrary waveform generation module 17 may further include a second arbitrary waveform generator 13 having multi-channel output terminals; although only one second arbitrary waveform generator 13 is used, multiple second IQ mixers 14 in the second IQ mixing module 18 are respectively connected to the multi-channel output terminals of the second arbitrary waveform generation module 17 and the multi-channel output terminals of the microwave source 8 to form multiple read-in signal generation channels. The specific structure can be referred to Figure 10 as shown.

[0253] Figure 10 In the system architecture shown, since multiple read-in signal transmission channels are required, correspondingly, the above-mentioned second arbitrary waveform generation module 17 may include multiple second arbitrary waveform generators 13, and each second arbitrary waveform generator 13 corresponds to one channel; or the second arbitrary waveform generation module 17 itself includes a second arbitrary waveform generator 13 having multi-channel output, and multiple output channels of the second arbitrary waveform generator 13 correspond to multiple read-in signal transmission channels.

[0254] On the same channel of the read-in signal, the output terminal of a second arbitrary waveform generator 13 is connected to the input terminal of a second IQ mixer 14, and the other input terminal of the second IQ mixer 14 is connected to the output terminal of the microwave source 8.

[0255] On the same channel, the output terminal of the second IQ mixer 14 is connected to the input terminal of a second signal distribution device 15.

[0256] In this way, the second combiner 19 has an input for multi-channel read-in signals. The second combiner 19 combines the multi-channel read-in signals and then outputs them. In this way, each channel uses a corresponding second signal distribution device 15. The signals coupled out by the multiple second signal distribution devices 15 are all combined by the second combiner 19, and then the same microwave source 8 is uniformly used for down-conversion to obtain signals that the quantum analyzer 3 can collect and analyze. This architecture not only realizes the expansion and integration of the multi-bit measurement and control circuits for the read-in signals, but also reduces the demand for the channels of the microwave source 8 in terms of hardware. While simplifying the structure, it saves the hardware cost.

[0257] The process of the measurement and control system 24 of the above quantum computer for real-time monitoring of the read-in signals is briefly described as follows:

[0258] The second arbitrary waveform generator 13 in the second arbitrary waveform generation module 17 emits the required multi-channel baseband signals, which are respectively input to the second IQ mixing module 18. In the second IQ mixing module 18, each second IQ mixer 14 mixes them with the microwave signals output by the microwave source 8 to generate high-frequency signals, that is, read-in signals. Then, after each second signal distribution device 15 in the second signal distribution module 23 respectively couples out a part of the read-in signals, they are combined to form one read-in signal. The read-in signal obtained after combination is connected to the demodulation mixing module 16, and then mixed with the microwave signals output by the microwave source 8 for down-conversion into signals that the quantum analyzer 3 can collect. When there is a problem with the signal emitted by the second arbitrary waveform generation module 17, or there is a problem with the second IQ mixing module 18, or the microwave source 8 does not emit signals normally, etc., the host computer 20 connected to the quantum analyzer 3 can know in real time. The microwave signals output by the microwave source 8 to the second IQ mixing module 18 are the same as the microwave signals output to the demodulation mixing module 16.

[0259] The above embodiments are improvements for both the control signal channel and the read-in signal channel simultaneously to achieve the monitoring of the control signals and / or the read-in signals, or to achieve the monitoring of whether the emission order of the two is abnormal.

[0260] Those skilled in the art can know from the records of the above embodiments that the improvement of the control signal channel in this application is similar to the improvement of the read-in signal channel. In specific implementation, only the control signal channel can be improved to achieve the monitoring of the control signals, or only the read-in signal channel can be improved to achieve the monitoring of the read-in signals, or both can be improved simultaneously to achieve the monitoring of both. Multiple possible implementation manners can refer to the description of the structure and principle of the foregoing embodiments. In addition, this application is not limited to the examples where the first signal is the above control signal and read-in signal, and can also be other signals in the quantum computer. As long as the technical solutions obtained based on the technical concept of this application should fall within the protection scope of this application.

[0261] In the above embodiments, the host computer 20 is connected to the microwave source 8 through the switch 21. Moreover, the host computer 20 is respectively connected to the first arbitrary waveform generator 6 (or the first arbitrary waveform generation module 11), the second arbitrary waveform generator 13 (or the second arbitrary waveform generation module 17), and the quantum signal analyzer through the switch 21. In a possible embodiment, the host computer 20 can also be directly connected to them without passing through the switch 21. The switch 21 can also be other replaceable network devices as long as they can realize the communication function.

[0262] In the above embodiments, the microwave signal output from the microwave source 8 to the second IQ mixer 14 or the second IQ mixing module 18 is the same as the microwave signal output to the demodulation call mixing module 16.

[0263] In the above embodiments, the second signal distribution device 15 can also be, for example, a power splitter or a directional coupler.

[0264] It can be understood that in the above embodiments, for the control signals and read-in signals of multiple channels, it is also possible to use multiple local oscillator signals for demodulation.

[0265] The measurement and control system in each of the above embodiments of the present application is a measurement and control system for a quantum computer. Preferably, the quantum computer is a superconducting quantum computer. Correspondingly, the quantum processing unit 22 is a superconducting quantum chip. However, alternatively, the quantum computer can also be an ion trap quantum computer, a photonic quantum computer, a topological quantum computer, a neutral atom quantum computer, a silicon-based quantum computer, or a nuclear magnetic resonance quantum computer, etc. Any suitable quantum computer. As long as it is an improvement idea or improvement scheme based on the measurement and control system of the quantum computer of the present invention, it should fall within the protection scope of the present application. It should be noted that for quantum computers of different systems, the quantum processing unit 22 may not necessarily be a chip. The structure, material, working principle, state, etc. of the quantum processing unit 22 may be different, but they are all processing units with quantum bits.

[0266] It should be noted that in the above technical solutions of this case, the same components are labeled with the same reference numerals. However, for different embodiments, some of the same components are labeled with different reference numerals for the necessary clear expression. For those skilled in the art, it can be understood according to the technical content recorded herein.

[0267] Based on the same inventive concept, embodiments of the present invention further provide a quantum computer and a signal monitoring method for a quantum computer. Since the principles of the problems solved by the quantum computer and the signal monitoring method for the quantum computer are similar to those of the aforementioned measurement and control system of the quantum computer, the implementation of the quantum computer and the signal monitoring method for the quantum computer can refer to the implementation of the aforementioned system, and the repeated parts will not be elaborated.

[0268] A quantum computer provided by an embodiment of the present invention, referring to Figure 7 as shown, includes: the measurement and control system 24 of the quantum computer as described above and a quantum processing unit 22;

[0269] The control signal monitoring unit 2 in the measurement and control system is connected to the quantum processing unit 22, and is used to couple out a part of the control signal sent by the control signal generating unit 1 in the measurement and control system, demodulate it and output it to the quantum analyzer 3 for acquisition and analysis, and output the remaining control signal to the quantum processing unit 22 for controlling quantum bits.

[0270] Further, the measurement and control system 24 of the quantum computer in the above quantum computer, referring to Figure 7 as shown, may further include: a host computer 20;

[0271] The host computer 20 is respectively connected to the control signal monitoring unit 2 and the quantum analyzer 3 in the measurement and control system 24 of the quantum computer;

[0272] The host computer 20 is used to control the control signal generating unit 1 to generate a control signal; and monitor whether the control signal is sent and whether it is abnormal according to the signals collected and analyzed by the quantum analyzer 3.

[0273] A signal monitoring method for a quantum computer provided by an embodiment of the present invention, which uses the aforementioned measurement and control system of the quantum computer to monitor the control signal to be transmitted.

[0274] In the above signal monitoring method for the quantum computer, the microwave signal output by the microwave source 8 to the first IQ mixer 7 or the first IQ mixing module 12 is the same as the microwave signal output to the demodulation mixer 5;

[0275] The microwave signal output by the microwave source 8 to the second IQ mixer 14 or the second IQ mixing module 18 is the same as the microwave signal output to the demodulation mixing module 16.

[0276] The quantum computer is a superconducting quantum computer. However, alternatively, the quantum computer may also be any suitable quantum computer such as an ion trap quantum computer, a photonic quantum computer, a topological quantum computer, a neutral atom quantum computer, a silicon-based quantum computer, or a nuclear magnetic resonance quantum computer, etc.

[0277] Further, in the specific implementation of the above signal monitoring method for a quantum computer, the following steps are included:

[0278] A control signal monitoring unit in the measurement and control system of the quantum computer partially couples out a part of the control signals generated by the control signal generating unit, demodulates them and outputs them to the quantum analyzer, and outputs the remaining control signals to the quantum processing unit for controlling quantum bits.

[0279] The quantum analyzer collects and analyzes the demodulated signals output by the control signal monitoring unit.

[0280] The host computer monitors whether the control signals are sent and whether they are abnormal according to the demodulated signals collected and analyzed by the quantum processing unit.

[0281] In one embodiment, the above signal monitoring method can also monitor the read-in signals to be transmitted by the measurement and control system of the aforementioned quantum computer; and when necessary, it can also monitor whether the order of the read-in signals and the control signals is correct.

[0282] For the monitoring process, reference can be made to the description of the embodiment of the measurement and control system of the aforementioned quantum computer, which will not be elaborated here.

[0283] Those skilled in the art should understand that the embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can be implemented in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can be implemented in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories and optical memories, etc.) containing computer-usable program codes.

[0284] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, and the combination of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processors of general-purpose computers, special-purpose computers, embedded processors, or other programmable data processing devices to generate a machine, such that the instructions executed by the processors of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0285] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the function specified in the flowchart(s) Figure 1 a flowchart or flowcharts and / or block(s) Figure 1 a block or blocks.

[0286] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable apparatus provide steps for implementing the function specified in the flowchart(s) Figure 1 a flowchart or flowcharts and / or block(s) Figure 1 a block or blocks.

[0287] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A measurement and control system for a quantum computer, characterized in that, Comprising: A signal generation unit, a signal monitoring unit, and a quantum analyzer; The signal generation unit is configured to generate a first signal for qubits in a quantum processing unit of a quantum computer to perform corresponding operations on the qubits; The input end of the signal monitoring unit is connected to the signal generation unit, and the output end is respectively connected to the quantum analyzer and the quantum processing unit; the signal monitoring unit is configured to partially couple out a part of the first signal generated by the signal generation unit, demodulate it and output it to the quantum analyzer, and output the remaining first signal to the quantum processing unit; The quantum analyzer is configured to collect and analyze the demodulated signal output by the control signal monitoring unit to monitor the first signal.

2. The measurement and control system according to claim 1, characterized in that The signal monitoring unit includes: a signal distribution device and a demodulation mixer; wherein: The signal distribution device is connected between the signal generation unit and the quantum processing unit; The input end of the demodulation mixer is respectively connected to the signal distribution device and the signal generation unit, and the output end of the demodulation mixer is connected to the quantum analyzer; The signal distribution device is configured to couple out a part of the first signal generated by the signal generation unit and output it to the demodulation mixer, and output the remaining first signal to the quantum processing unit; The demodulation mixer is configured to demodulate the first signal coupled out by the signal distribution device and output it to the quantum analyzer; The quantum analyzer is further configured to collect and analyze the first signal demodulated by the demodulation mixer to monitor the first signal.

3. The measurement and control system according to claim 2, wherein The signal generation unit includes: an arbitrary waveform generator, an IQ mixer, and a microwave source; The input ends of the IQ mixer are respectively connected to the arbitrary waveform generator and the microwave source; the output end of the IQ mixer is connected to the signal distribution device; The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the signal distribution device, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer; The arbitrary waveform generator is configured to transmit a baseband signal to the IQ mixer, the microwave source outputs a local oscillator signal to the IQ mixer, and the IQ mixer mixes the baseband signal and the local oscillator signal and then outputs the first signal to the signal distribution device; The demodulation mixer is specifically configured to mix the first signal output by the signal distribution device with the local oscillator signal output by the microwave source, down-convert it into a signal that the quantum analyzer can collect and analyze, and output it to the quantum analyzer.

4. The measurement and control system according to claim 1, wherein The signal monitoring unit includes: a signal distribution module, a combiner, and a demodulation mixer; The combiner is arranged between the signal distribution module and the demodulation mixer; The signal distribution module includes a plurality of signal distribution devices; the plurality of signal distribution devices are connected to the combiner; The plurality of signal distribution devices are respectively connected to the multi-channel output ends of the signal generation unit; each signal distribution device is configured to partially couple out the first signal of the corresponding channel; The combiner is used to combine the signals obtained by coupling multiple signal distribution devices and then output the combined signals; The demodulation mixer is used to demodulate the signals output after combination by the combiner and then input the demodulated signals into the quantum analyzer.

5. The measurement and control system according to claim 4, characterized in that, The signal generation unit specifically includes: an arbitrary waveform generation module, an IQ mixing module, and a microwave source; The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the combiner, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer; The arbitrary waveform generation module includes a plurality of arbitrary waveform generators; The IQ mixing module includes a plurality of IQ mixers; The plurality of IQ mixers in the IQ mixing module are respectively and correspondingly connected to the plurality of arbitrary waveform generators in the arbitrary waveform generation module and the multi-channel output ends of the microwave source to form a plurality of first signal generation channels; wherein, the input ends of each IQ mixer are respectively connected to the microwave source and the arbitrary waveform generator in the same channel; the output ends of each IQ mixer are respectively and correspondingly connected to the input ends of the signal distribution devices in the same channel of the signal distribution module; The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the combiner, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer; The arbitrary waveform generator is used to transmit a baseband signal to the IQ mixer, the microwave source is used to output a local oscillator signal to the IQ mixer, and the IQ mixer is used to mix the baseband signal and the local oscillator signal and output the first signal to the signal distribution device; The microwave source is further used to output a local oscillator signal for demodulating the first signal to the demodulation mixer; The demodulation mixer is specifically used to mix the first signal output after combination by the combiner with the local oscillator signal for demodulating the control signal, and down-convert it into a signal that can be collected and analyzed by the quantum analysis.

6. The measurement and control system according to claim 4, wherein The signal generation unit specifically includes: an arbitrary waveform generation module, an IQ mixing module, and a microwave source; The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the combiner, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer; The arbitrary waveform generation module includes an arbitrary waveform generator with multi-channel output ends; The IQ mixing module includes a plurality of IQ mixers; The plurality of IQ mixers in the IQ mixing module are respectively and correspondingly connected to the multi-channel output ends of the arbitrary waveform generation module and the multi-channel output ends of the microwave source to form a plurality of first signal generation channels; wherein, the input ends of each IQ mixer are respectively connected to the output ends of the microwave source and the arbitrary waveform generator in the same channel; the output ends of each IQ mixer are respectively and correspondingly connected to the input ends of the signal distribution devices in the same channel of the signal distribution module; The input ends of the demodulation mixer are respectively connected to the quantum processing unit, the output end of the multiplexer, and the microwave source, and the output end of the demodulation mixer is connected to the quantum analyzer; The arbitrary waveform generator is used to transmit a baseband signal to the IQ mixer, the microwave source is used to output a local oscillator signal to the IQ mixer, and the IQ mixer is used to mix the baseband signal and the local oscillator signal and output the first signal to the signal distribution device; The microwave source is further used to output a local oscillator signal for demodulating the first signal to the demodulation mixer; The demodulation mixer is specifically used to mix the signal output after being combined by the first multiplexer with the local oscillator signal for demodulating the first signal, and down-convert it into a signal that can be collected and analyzed by the quantum analyzer.

7. The measurement and control system according to any one of claims 3, 5, and 6, characterized in that The local oscillator signal output by the microwave source to the IQ mixer or the IQ mixing module is the same as the local oscillator signal output to the demodulation mixer.

8. The measurement and control system according to claim 2 or 4, characterized in that, The signal distribution device is a power splitter or a directional coupler.

9. The measurement and control system according to claim 1, characterized in that, The first signal is a read-in signal, and the signal generation unit is used to generate a read-in signal for the qubits in the quantum processing unit to read the states of the qubits.

10. The measurement and control system according to claim 1, wherein, The measurement and control system is the measurement and control system in a superconducting quantum computer, and the quantum processing unit is a superconducting quantum chip.

11. A quantum computer, characterized in that, Comprising: The measurement and control system of the quantum computer and the quantum processing unit according to any one of claims 1-10; The signal monitoring unit in the measurement and control system is connected to the quantum processing unit, and is used to couple out a part of the first signal sent by the signal generation unit in the measurement and control system, demodulate it and output it to the quantum analyzer for collection and analysis, and output the remaining first signal to the quantum processing unit for corresponding actions on the qubits.

12. The quantum computer according to claim 11, wherein, The measurement and control system of the quantum computer further includes: a host computer; The host computer is respectively connected to the signal sending unit and the quantum analyzer in the measurement and control system; The host computer is used to control the signal generation unit to generate the first signal; and monitor whether the first signal is sent and whether it is abnormal according to the signal collected and analyzed by the quantum analyzer.

13. A signal monitoring method for a quantum computer, characterized in that, The method uses the measurement and control system of the quantum computer according to any one of claims 1-10 to monitor the first signal to be transmitted.

14. The method according to claim 13, wherein Monitoring the first signal to be transmitted includes: The signal monitoring unit in the measurement and control system of the quantum computer couples out a part of the first signal generated by the signal generation unit, demodulates it and outputs it to the quantum analyzer, and outputs the remaining first signal to the quantum processing unit; The quantum analyzer collects and analyzes the demodulated signal output by the signal monitoring unit; The host computer monitors whether the first signal is sent and whether it is abnormal according to the demodulated signal collected and analyzed by the quantum processing unit.

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