A quantum computing system and a nuclear magnetic resonance quantum computer

Abstract

The utility model discloses a quantum computing system and nuclear magnetic resonance quantum computer, this quantum computing system includes: main resonance coil, probe resonant circuit, main control module, magnet module and sample module, probe resonant circuit includes first varactor diode circuit, first varactor diode circuit one end connects main resonance coil, and the other end ground connection, sample module is equipped with the sample of quantum bit carrier, main resonance coil is connected with main control module, and is set between main control module and sample module, main resonance coil is used for inducting the first nuclear magnetic signal of atomic nucleus in the sample of quantum bit carrier as quantum bit when happening nuclear magnetic resonance, main control module connects first varactor diode circuit, is used for sending first bias voltage signal for adjusting the resonance frequency of main resonance coil to first varactor diode circuit. Based on varactor diode circuit and bias voltage signal, realize resonance frequency adjustment.

Description

Technical Field

[0001] This utility model relates to the field of quantum information technology, and in particular to a quantum computing system and a nuclear magnetic resonance quantum computer. Background Technology

[0002] Currently, there are many physical experimental platforms upon which quantum computing systems rely to realize quantum computing, such as spin quantum systems based on nuclear magnetic resonance (NMR), superconducting quantum circuits (superconducting quantum chips), ion trapping systems, and photonic quantum systems. Among these, spin quantum systems based on nuclear magnetic resonance are the earliest developed, most mature, and have the most implemented quantum algorithms. Quantum computing systems based on nuclear magnetic resonance can realize a wide range of quantum computing algorithms at room temperature and pressure, have mature radio frequency measurement and control technology, and require simple experimental conditions.

[0003] Nuclear magnetic resonance quantum computing systems utilize the spins of atomic nuclei in a strong magnetic field as qubits for quantum computing, and achieve quantum entanglement between different qubits through J-coupling between different atomic nuclei in the same molecule.

[0004] Nuclear magnetic resonance (NMR) utilizes a magnetic field source (magnet module) to excite non-zero spin atomic nuclei (spin nuclei) in a sample, causing polarization level splitting (Zeeman splitting). A specific frequency radio frequency pulse is used to excite the nuclei, causing them to absorb energy and undergo energy level transitions. When the radio frequency pulse stops, the nuclei return from the excited state to the ground state, releasing energy and generating NMR signals. These signals are sensed by the probe's main resonant coil and converted into electrical signals. When the atomic nuclei (spin nuclei) are in a magnetic field source of intensity B0, in addition to their spin, they also move around the magnetic field source B0. This motion is very similar to that of a gyroscope and is called Larmor precession. The frequency of precession in the magnetic field source B0 is called the Larmor frequency. When the frequency of the radio frequency pulse matches the Larmor frequency, the NMR phenomenon occurs.

[0005] The Larmor frequency is determined by both the magnetic field strength and the gyrometry of the atomic nuclei, f0 = γB0 / 2π, where γ is the gyrometry ratio, a characteristic constant of the atomic nucleus, and different nuclei have different gyrometry ratios. When the sample changes, if the types of atomic nuclei involved in the sample are different, the gyrometry ratio γ will also be different. Furthermore, since the magnetic field strength generated by the magnet module is sensitive to temperature, the magnetic field strength B0 changes when the external temperature changes. Therefore, both sample replacement and temperature changes will cause changes in the Larmor frequency (NMR signal frequency), resulting in distortion of the measured NMR signal. Utility Model Content

[0006] In view of the above problems, this utility model is proposed to provide a quantum computing system and nuclear magnetic resonance quantum computer that overcomes or at least partially solves the above problems.

[0007] In a first aspect, this utility model provides a quantum computing system, including: a main resonant coil, a probe resonant circuit, a main control module, a magnet module, and a sample module;

[0008] The probe resonant circuit includes a first varactor diode circuit, one end of which is connected to the main resonant coil and the other end is grounded.

[0009] The sample module contains a sample serving as a quantum bit carrier; the sample serving as a quantum bit carrier is placed in the magnetic field of the magnet module.

[0010] The main resonant coil is disposed in the magnetic field of the magnet module, connected to the main control module, and positioned between the main control module and the sample module;

[0011] The main resonant coil is used to sense the first nuclear magnetic signal when the atomic nuclei that serve as qubits in the sample that serve as qubit carriers undergo nuclear magnetic resonance.

[0012] The main control module is connected to the first varactor diode circuit;

[0013] The main control module is used to send a first bias voltage signal to the first varactor diode circuit to adjust the resonant frequency of the main resonant coil.

[0014] In one embodiment, the quantum computing system further includes a control coil and a field-locking coil;

[0015] The sample module also contains a sample for field locking; the sample for field locking is placed in the magnetic field of the magnet module.

[0016] The control coil and the field-locking coil are disposed in the magnetic field of the magnet module, connected to the main control module, and positioned between the main control module and the sample module;

[0017] The control coil is used to transmit radio frequency pulses of at least one frequency corresponding to the control signal sent by the main control module.

[0018] The field-locking coil is used to transmit radio frequency pulses of at least one frequency corresponding to the field-locking signal according to the field-locking signal sent by the main control module, and to sense a second nuclear magnetic signal when nuclear magnetic resonance occurs between the atomic nuclei used for field-locking in the sample.

[0019] The main control module is also used to send the locking signal to the locking coil and receive and demodulate the second nuclear magnetic resonance signal corresponding to the locking signal when not performing quantum computing; and to send the control signal to the control coil and receive and demodulate the first nuclear magnetic resonance signal corresponding to the control signal when performing quantum computing.

[0020] In one embodiment, the quantum computing system further includes a field-locked resonant circuit, which includes a second varactor diode circuit, one end of which is connected to the field-locked coil and the other end is grounded.

[0021] The main control module is connected to the second varactor diode circuit;

[0022] The main control module is also used to send a second bias voltage signal to the second varactor diode circuit to adjust the resonant frequency of the field-locking coil when not performing quantum computing, so as to adjust the resonant frequency of the field-locking coil.

[0023] In one embodiment, the main resonant coil and the field-locking coil share the same coil; the probe resonant circuit and the field-locking resonant circuit are the same circuit, or the probe resonant circuit and the field-locking resonant circuit are connected on both sides of the same coil;

[0024] or,

[0025] The main resonant coil and the field-locking coil are arranged adjacent to each other.

[0026] In one embodiment, the quantum computing system further includes a control resonant circuit, which includes a third varactor diode circuit, one end of which is connected to the control coil and the other end is grounded.

[0027] The main control module is connected to the third varactor diode circuit;

[0028] The main control module is also used to send a third bias voltage signal to the third varactor diode circuit to adjust the resonant frequency of the control coil, so as to adjust the resonant frequency of the control coil.

[0029] In one embodiment, the main resonant coil is a helical coil, and the control coil is a cage coil;

[0030] Alternatively, the main resonant coil and the control coil share the same coil; the probe resonant circuit and the control resonant circuit are the same circuit.

[0031] In one embodiment, the number of probe resonant circuits is two sets, and the two sets of probe resonant circuits are respectively connected to both sides of the main resonant coil;

[0032] The sample serving as the carrier of qubits includes atomic nuclei at two different frequencies that serve as qubits.

[0033] The main resonant coil is specifically used to sense two first nuclear magnetic signals when the atomic nuclei at two different frequencies that serve as quantum bits in the sample that are quantum bit carriers undergo nuclear magnetic resonance.

[0034] The main control module is connected to two of the first varactor diode circuits;

[0035] The main control module is specifically used to send a first bias voltage signal to each of the two first varactor diode circuits to adjust the resonant frequency of the corresponding main resonant coil.

[0036] In one embodiment, the number of control resonant circuits is two sets, and the two sets of control resonant circuits are respectively connected to both sides of the control coil;

[0037] The control coil is used to transmit radio frequency pulses at frequencies corresponding to the two sets of control signals sent by the main control module.

[0038] The main control module is connected to the two third varactor diode circuits;

[0039] Specifically, when performing quantum computing, the main control module sends two sets of control signals corresponding to the two different frequency atomic nuclei in the sample that serve as qubit carriers; and sends third bias voltage signals to the two third varactor diode circuits to adjust the resonant frequency of the corresponding control coils.

[0040] In one embodiment, the main control module includes: a programmable logic device, a digital-to-analog converter module, and an analog-to-digital converter module, wherein the programmable logic device is connected to the digital-to-analog converter module and the analog-to-digital converter module respectively; wherein:

[0041] The programmable logic device is used to modulate and generate the control signal and the field-locking signal, and to demodulate the second nuclear magnetic signal returned by the field-locking coil and the first nuclear magnetic signal returned by the main resonant coil;

[0042] The digital-to-analog conversion module is used to convert the control signal or field-locking signal into a digital-to-analog signal, and then into a corresponding analog signal, so as to send it to the control coil or the field-locking coil.

[0043] The analog-to-digital conversion module is used to convert the second nuclear magnetic resonance signal returned by the field-locking coil and the first nuclear magnetic resonance signal returned by the main resonant coil into analog-to-digital signals, convert them into corresponding digital signals, and send them to the programmable logic device.

[0044] In one embodiment, the quantum computing system further includes: at least one first radio frequency switch, at least one channel control signal processing module, and at least one channel first broadband radio frequency amplification module corresponding to the at least one channel control signal processing module.

[0045] Each control signal processing module and its corresponding first broadband RF amplification module are connected to a first RF switch and switch operation via the first RF switch;

[0046] At least one channel of the control signal processing module and the at least one first radio frequency switch are connected between the digital-to-analog converter module of the main control module and the control resonant circuit;

[0047] At least one channel of the first broadband RF amplifier module and at least one first RF switch are connected between the analog-to-digital conversion module of the main control module and the probe resonant circuit;

[0048] The first radio frequency switch conducts the control coil, control resonant circuit, control signal processing module, and main control module when the control signal is transmitted; and conducts the main resonant coil, probe resonant circuit, first broadband radio frequency amplification module, and main control module when the control signal is turned off and a non-locked field signal is transmitted.

[0049] In one embodiment, the first broadband radio frequency amplification module includes: a first broadband filter circuit and a first low-noise amplification circuit;

[0050] The first broadband filter circuit is used to filter the first nuclear magnetic signal induced by the main resonant coil;

[0051] The first low-noise amplifier circuit is used to amplify the filtered first nuclear magnetic resonance signal.

[0052] In one embodiment, the first broadband filtering circuit is a broadband filter.

[0053] In one embodiment, the control signal processing module includes a power amplifier circuit; the power amplifier circuit is used to amplify the control signal emitted by the main control module.

[0054] In one embodiment, the quantum computing system further includes: a lock field signal transmission module, a second broadband radio frequency amplification module, and a second radio frequency switch;

[0055] The field-locking signal transmitting module and the second broadband radio frequency amplification module are respectively connected to the second radio frequency switch, and their operation is switched through the second radio frequency switch;

[0056] The field-locking signal transmitting module and the second radio frequency switch are connected between the digital-to-analog converter module of the main control module and the field-locking resonant circuit;

[0057] The second broadband RF amplifier module and the second RF switch are connected between the analog-to-digital converter module of the main control module and the field-locked resonant circuit.

[0058] In one embodiment, the second broadband RF amplification module includes: a second broadband filter circuit and a second low-noise amplification circuit;

[0059] The second broadband filter circuit is used to filter the second nuclear magnetic signal induced by the field-locking coil;

[0060] The second low-noise amplifier circuit is used to amplify the filtered second nuclear magnetic resonance signal.

[0061] In one embodiment, the second broadband filtering circuit is a broadband filter.

[0062] In one embodiment, the field-locking signal transmitting module and one channel of the multiple-channel control signal processing module are configured to share the same circuit;

[0063] The second broadband RF amplifier module and one channel of the first broadband RF amplifier module with multiple channels are configured to share the same circuit.

[0064] In one embodiment, the field-locking signal transmitting module and the control signal processing module for all channels are configured as the same circuit;

[0065] The second broadband RF amplifier module and the first broadband RF amplifier module for all channels are configured to use the same circuit.

[0066] In one embodiment, the varactor diode circuit includes a distributed varactor diode array, or at least one varactor diode and at least one fixed capacitor connected in parallel.

[0067] In one embodiment, the probe resonant circuit further includes an impedance matching capacitor;

[0068] The main resonant coil is connected in series with the impedance matching capacitor.

[0069] In one embodiment, the quantum computing system further includes a power supply module;

[0070] The main control module also includes a power management module;

[0071] The power management module is used to control the power module to output a corresponding bias voltage signal based on a determined bias voltage.

[0072] In one embodiment, the quantum computing system further includes: a temperature detection module;

[0073] The temperature detection module is connected to the main control module and is located on the magnet module. It is used to detect the temperature of the magnet module and send the temperature signal to the main control module.

[0074] The main control module is also used to determine whether the temperature of the magnet module has changed based on the received temperature signal.

[0075] Secondly, this utility model embodiment provides a nuclear magnetic resonance quantum computer, including: a quantum computing host and a quantum computing system as described above;

[0076] The quantum computing host is communicatively connected to the main control module of the quantum computing system.

[0077] The beneficial effects of the above-mentioned technical solutions provided by the embodiments of this utility model include at least the following:

[0078] The quantum computing system and nuclear magnetic resonance quantum computer provided in this embodiment of the invention utilize a main resonant coil and a varactor diode circuit in the probe resonant circuit. The main resonant coil senses the first nuclear magnetic resonance signal when the atomic nuclei in the sample, which serve as the carrier of the qubits, undergo nuclear magnetic resonance. When the resonant frequency of the main resonant coil needs to be adjusted, the main control module sends a corresponding bias voltage signal to change the capacitance value of the varactor diode circuit, thus achieving simple and efficient resonant frequency adjustment. In this scheme, the main control module sends a bias voltage signal to change the capacitance value of the varactor diode circuit, achieving rapid adjustment of the resonant circuit frequency to the optimal frequency of the corresponding sample. The frequency adjustment speed can reach the nanosecond level, and the frequency adjustment accuracy can reach 0.01MHz, greatly improving the detection efficiency and accuracy of the nuclear magnetic resonance signal, and enhancing the quantum computing efficiency of the quantum computing system.

[0079] The quantum computing system and nuclear magnetic resonance quantum computer provided in this embodiment of the invention, compared with the prior art of changing the capacitance value in the circuit through manual mechanical adjustment mechanisms, adopt an electronic tuning method based on varactor diode circuits and bias voltage. This not only increases the frequency adjustment range, making it adaptable to most nuclear magnetic resonance detection scenarios, including high-frequency bands, but also avoids the electromagnetic interference problems caused by mechanical adjustment mechanisms. Compared with traditional methods of manually soldering other capacitors or mechanically adjusting capacitors, the varactor diode circuit allows for a reduction in probe size, resulting in a more compact structure, higher integration, and smaller footprint for the quantum computing system. Furthermore, the electronic tuning method facilitates intelligent control using standardized digital intelligent control interfaces, making it easy to integrate with modern detection systems.

[0080] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0081] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0082] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0083] Figure 1 This is a schematic diagram of the quantum computing system in an embodiment of the present invention;

[0084] Figure 2 This is a schematic diagram of the probe resonant circuit in an embodiment of the present invention;

[0085] Figure 3 This is another structural schematic diagram of the quantum computing system in this embodiment of the present invention;

[0086] Figure 4 This is a schematic diagram of the FID signal collected in an embodiment of this utility model;

[0087] Figure 5 To Figure 4 The diagram shows the FFT signal obtained by transforming the NMR signal.

[0088] Figure 6 This is another schematic diagram of the probe resonant circuit in this embodiment of the present invention;

[0089] Figure 7 This is a schematic diagram of the molecular structure of dimethyl phosphite (C2H7O3P) in the embodiments of this utility model;

[0090] Figure 8 This is a schematic diagram of the relevant circuitry of the quantum computing system in Embodiment 1 of this utility model;

[0091] Figure 9 This is a schematic diagram of the relevant circuitry of the quantum computing system in Embodiment 2 of this utility model;

[0092] Figure 10 This is a schematic diagram of the relevant circuitry of the quantum computing system in Embodiment 3 of this utility model;

[0093] Figure 11This is a schematic diagram of the structure of the nuclear magnetic resonance quantum computer according to an embodiment of the present invention.

[0094] Explanation of reference numerals in the attached figures:

[0095] 100. Quantum Computing System; 200. Quantum Computing Host; 1. Probe Resonant Circuit; L1. Main Resonant Coil; DIODE1. First Varactor Diode Circuit; C2. Impedance Matching Capacitor; Term1. Indicates Virtual Port; 2. Main Control Module; 3. Magnet Module; 4. Sample Module; 5. Field Lock Coil; 6. Field Lock Resonant Circuit; 7. Control Coil; 8. Control Resonant Circuit; 9. Programmable Logic Device; 10. Digital-to-Analog Conversion Module; 11. Analog-to-Digital Conversion Module; 12. Control Signal Processing Module; 13. First broadband RF amplifier module; 14. First RF switch; 15. Power amplifier circuit; 16. First broadband filter circuit; 17. First low-noise amplifier circuit; 18. Field lock signal transmission module; 19. Second broadband RF amplifier module; 20. Second RF switch; 21. Second broadband filter circuit; 22. Second low-noise amplifier circuit; 23. Power supply module; 24. Power management module; 25. Temperature detection module; 26. Temperature control module; 27. Shimming coil; 28. Shimming current source. Detailed Implementation

[0096] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0097] In existing technologies, nuclear magnetic resonance quantum computers utilize magnetic modules (such as superconducting coils) as magnetic field sources. To measure the NMR signals of different types of atomic nuclei, different resonant frequencies are typically set in a signal tuning circuit, allowing the probe to receive signals of different frequencies at a single port of the circuit, as described in patent application number 2021115991365. This fixed resonant frequency method is only applicable to a limited number of types of atomic nuclei, and manually soldering additional capacitors is required to change the resonant frequency.

[0098] With the diversification of testing needs, fixed-frequency probes can no longer meet the testing requirements of different samples. Researchers have attempted to use mechanical adjustment methods, adjusting the probe frequency by changing the capacitor plate spacing or coil position. In recent years, with technological advancements, tuning schemes based on variable capacitors have emerged, employing NMR probes with adjustable capacitors where the resonant frequency is changed by mechanically adjusting the capacitance value using a knob. While these mechanical adjustment schemes achieve basic frequency adjustment, their mechanical mechanisms inevitably suffer from wear and tear, affecting the equipment's lifespan. After prolonged use, accuracy significantly decreases, severely impacting testing reliability. Furthermore, the mechanical adjustment process is time-consuming, typically requiring several seconds or even longer to complete frequency switching, failing to meet rapid testing requirements. Especially at high frequencies, conventional mechanical adjustment methods often struggle to achieve stable and reliable frequency control. In addition, the mechanical adjustment mechanism inevitably leads to an excessively large probe size, posing challenges to equipment integration and hindering the compact design of modern testing equipment. Electromagnetic interference directly affects the quality of the detection signal. These technological bottlenecks severely restrict the development and application expansion of NMR testing technology. More importantly, existing solutions lack intelligent control interfaces, have low levels of automation, and are difficult to integrate well with modern testing systems. These shortcomings directly affect testing efficiency and result accuracy, becoming major obstacles to technological development and failing to meet increasingly stringent testing requirements.

[0099] The quantum computing system provided in this embodiment of the present invention refers to... Figure 1 and Figure 2 As shown, it includes: main resonant coil L1, probe resonant circuit 1, main control module 2, magnet module 3, and sample module 4; wherein:

[0100] The probe resonant circuit 1 includes a first varactor diode circuit DIODE1, one end of which is connected to the main resonant coil L1, and the other end is grounded.

[0101] Sample module 4 contains a sample that serves as a carrier of qubits; the sample that serves as a carrier of qubits is placed in the magnetic field of magnet module 3;

[0102] The main resonant coil L1 is placed in the magnetic field of the magnet module 3, connected to the main control module 2, and positioned between the main control module 2 and the sample module 4;

[0103] The main resonant coil L1 is used to sense the first nuclear magnetic signal when the atomic nuclei that are qubits in the sample, which are qubit carriers, undergo nuclear magnetic resonance.

[0104] Main control module 2 is connected to the first varactor diode circuit DIODE1;

[0105] The main control module 2 is used to send a first bias voltage signal to the first varactor diode circuit DIODE1 based on the pre-configured relationship between the resonant frequency and the bias voltage, so as to adjust the resonant frequency of the main resonant coil L1; and to receive and demodulate the first nuclear magnetic resonance signal.

[0106] In this embodiment of the invention, when the ambient temperature of the magnet module 3 changes, the magnet module 3 will be affected by the temperature, and the magnetic field strength will change, causing the frequency of the NMR signal observed by the main resonant coil L1 (i.e., the actual NMR signal frequency of the first NMR signal) to change. At this time, the actual resonant frequency of the main resonant coil L1 will be inconsistent with the observed NMR signal frequency. The NMR signal affected by the temperature is received by the main control module 2, but it will affect the quality of the observed signal. In this embodiment of the invention, the main control module 2 can output a bias voltage signal to the first varactor diode circuit DIODE1 to adjust the resonant frequency of the main resonant coil L1 to match the actual NMR signal frequency at the current temperature. Similarly, when the test sample is changed, the gyromagnetic ratio γ changes, causing the frequency of the NMR signal observed by the main resonant coil L1 to change. At this time, the actual resonant frequency of the main resonant coil L1 will be inconsistent with the observed NMR signal frequency. The NMR signal (first NMR signal) observed by the main resonant coil L1 is received by the main control module 2, but it will affect the quality of the observed signal. In this embodiment of the invention, the main control module 2 can also output a bias voltage signal to the first varactor diode circuit DIODE1 to adjust the resonant frequency of the main resonant coil L1, adapting it to the actual NMR signal frequency of the current sample. Only when the resonant frequency of the main resonant coil L1 and the actual NMR signal frequency are kept the same can the best signal observation effect be achieved. This scheme can ensure that the signal quality of the entire system will not degrade due to temperature changes or sample replacement.

[0107] In one embodiment, refer to Figure 2 As shown, the probe resonant circuit 1 also includes an impedance matching capacitor C2;

[0108] The main resonant coil L1 is connected in series with the impedance matching capacitor C2.

[0109] In this embodiment of the invention, the probe resonant circuit 1 employs an LC resonant circuit. By connecting the first varactor diode circuit DIODE1 in parallel with the main resonant coil L1, the main resonant coil L1 is matched to its resonant frequency. Then, it is connected in series with the impedance matching capacitor C2. Impedance matching is achieved through the selection of parameters for the main resonant coil L1, the first varactor diode circuit DIODE1, and the capacitor C2. (Refer to...) Figure 2As shown, Term1 in the circuit represents a virtual port with an impedance matched to 50 ohms, signifying the achievement of 50Ω impedance matching. By applying a bias voltage to the first varactor diode circuit DIODE1, DIODE1 can be equivalent to a capacitor in the circuit. The capacitance value of the first varactor diode circuit DIODE1 changes with the applied voltage, thereby achieving simple and efficient resonant frequency adjustment, enabling the main resonant coil L1 to operate at the target resonant frequency, reducing noise generated by non-resonant frequencies, and improving signal detection efficiency and result accuracy. For NMR signals of different frequencies, the same main resonant coil L1 can receive NMR signals of different frequencies by adjusting the resonant frequency. In this embodiment of the invention, since the values ​​of the main resonant coil L1 and the impedance matching capacitor C2 are known, the frequency of the main resonant coil L1 is measured by continuously applying different bias voltage signals to the first varactor diode circuit DIODE1. This yields a pre-configured relationship between the resonant frequency and the bias voltage of the main resonant coil. This relationship between the resonant frequency and the bias voltage of the configured main resonant coil L1 can be pre-built into the main control module 2 as a data table. When it is necessary to adjust the resonant frequency of the main resonant coil L1, the operator can determine the first bias voltage signal to be sent to the first varactor diode circuit based on the pre-configured relationship between the resonant frequency and the bias voltage of the main resonant coil, thereby quickly adjusting the resonant frequency of the main resonant coil L1.

[0110] In this embodiment of the present invention, the first varactor diode circuit DIODE1 can be implemented using a distributed varactor diode array, or by connecting at least one varactor diode and at least one fixed capacitor in parallel. For example, refer to... Figure 2 As shown, the first varactor diode circuit DIODE1 is a varactor diode, and the cathode of the varactor diode is... Figure 2 When a reverse bias voltage signal is applied to point A, the varactor diode can be equivalent to a capacitor in the circuit.

[0111] In this embodiment of the invention, the impedance matching capacitor C2 may include at least two fixed capacitors connected in parallel.

[0112] In one embodiment, reference is made to Figure 3 As shown, the quantum computing system described above also includes a field-locking coil 5 and a control coil 7;

[0113] Sample module 4 also contains a sample for field locking; the sample for field locking is placed in the magnetic field of magnet module 3;

[0114] The locking coil 5 and the control coil 7 are placed in the magnetic field of the magnet module 3, connected to the main control module 2, and positioned between the main control module 2 and the sample module 4;

[0115] The field-locking coil 5 is used to transmit radio frequency pulses of at least one frequency corresponding to the field-locking signal sent by the main control module 2, and to transmit a second nuclear magnetic signal when the sample applied to the field-locking undergoes nuclear magnetic resonance with the atomic nuclei used for field-locking.

[0116] The control coil 7 is used to transmit radio frequency pulses of at least one frequency corresponding to the control signal sent by the main control module 2.

[0117] The main control module 2 is also used to send the locking signal to the locking coil and receive and demodulate the second nuclear magnetic resonance signal corresponding to the locking signal when not performing quantum computing; and to send the control signal to the control coil and receive and demodulate the first nuclear magnetic resonance signal corresponding to the control signal when performing quantum computing.

[0118] The first or second NMR signal actually acquired by the main control module 2 is a free induction decay (FID) signal, such as... Figure 4 As shown. The main control module 2 performs a Fast Fourier Transform (FFT) on the FID signal to obtain a frequency-domain NMR signal (FFT signal), including a first frequency-domain NMR signal and a second frequency-domain NMR signal, as shown. Figure 5 As shown, the FFT signal will have a peak height significantly higher than the noise floor. The frequency change of the NMR signal is very obvious in the frequency domain NMR signal spectrum. Therefore, it is possible to clearly observe whether the peak has shifted in the spectrum. Based on the magnitude of the frequency after the peak shift, the actual NMR signal frequency of the first NMR signal or the actual frequency of the second NMR signal can be observed.

[0119] Furthermore, the main control module 2 has a frequency sweep function, which scans the spectrum of the entire frequency domain NMR signal to identify whether it is an NMR signal. The judgment criteria include indicators such as peak height range and signal-to-noise ratio range, and parameters such as the frequency sweep range can be set in advance.

[0120] In this embodiment of the invention, in sample module 4, under the same magnetic field strength and temperature conditions, the ratio of the nuclear magnetic resonance frequency of the nuclei used as qubit carriers to the nuclear magnetic resonance frequency of the nuclei used as lock fields remains constant. Therefore, regardless of changes in external temperature and magnetic field, since the nuclei used as qubit carriers and the nuclei used as lock fields are always under the same magnetic field strength and temperature, the ratio of their nuclear magnetic resonance frequencies remains constant. By transmitting a lock field signal and inducing a second nuclear magnetic resonance signal through lock field coil 5, main control module 2 can obtain the frequency domain nuclear magnetic resonance signal corresponding to the second nuclear magnetic resonance signal through fast Fourier transform. The frequency of the second nuclear magnetic resonance signal is obtained by observing the spectrum of the frequency domain nuclear magnetic resonance signal. After obtaining the frequency of the second nuclear magnetic resonance signal, the actual nuclear magnetic resonance signal frequency of the first nuclear magnetic resonance signal is calculated based on the ratio of the nuclear magnetic resonance frequencies of the first and second nuclear magnetic resonance signals. This calculation process can be implemented by main control module 2 or by an operator using other computing devices. The actual nuclear magnetic resonance signal frequency of the first nuclear magnetic resonance signal is the resonant frequency of the main resonant coil L1 that needs to be adjusted.

[0121] When the ambient temperature of magnet module 3 changes, since both temperature and NMR signal frequency change slowly, the main control module 2 can quickly determine the actual NMR signal frequency of the first NMR signal based on the ratio of the NMR resonance frequencies of the first and second NMR signals, while locking the frequency of the second NMR signal through the field-locking coil 5. Thus, the operator can determine the actual NMR signal frequency of the first NMR signal, i.e., the bias voltage corresponding to the resonant frequency of the main resonant coil, based on the pre-configured relationship between the resonant frequency and the bias voltage. The main control module 2 then sends the corresponding bias voltage signal to the first varactor diode circuit DIODE1 to quickly adjust the resonant frequency.

[0122] If the sample is changed, the frequency may be lost instantaneously during quantum computing, and the first NMR signal will also disappear. A frequency scan can be initiated via the main control module 2 to scan the spectrum of the frequency-domain NMR signal within a set sweep range to identify the new frequency-domain NMR signal and find its frequency. After finding the frequency, the operator determines the frequency of the new first NMR signal based on the new frequency-domain NMR signal frequency as the actual NMR signal frequency. Then, based on the pre-configured relationship between the resonant frequency and the bias voltage, the bias voltage of the first varactor diode circuit DIODE1 is determined, and the corresponding bias voltage signal is sent via the main control module 2 to quickly adjust the resonant frequency.

[0123] If the sample is changed, the frequency may be lost instantaneously without quantum computing, and the second NMR signal will also disappear. A frequency scan can be initiated via the main control module 2 to scan the spectrum of the frequency-domain NMR signal within a set sweep range to identify the new frequency-domain NMR signal and find its frequency. After finding the frequency, the operator can determine the frequency of the second NMR signal based on the frequency of the new frequency-domain NMR signal. Then, based on the ratio of the resonant frequencies of the first and second NMR signals, the actual NMR signal frequency of the first NMR signal is calculated. Based on the pre-configured relationship between the resonant frequency and the bias voltage, the bias voltage of the first varactor diode circuit DIODE1 is determined, and the corresponding bias voltage signal is sent via the main control module 2 to quickly adjust the resonant frequency.

[0124] When quantum computing is performed, the first NMR signal may disappear, or when quantum computing is not performed, the second NMR signal may disappear. This could indicate either a sample replacement or that the original sample was removed but no new sample was placed in it. To determine the actual cause, the operator can use the main control module 2 to continuously send control signals multiple times at set time intervals, sweeping the frequency within a set range. By observing the spectrum of the frequency domain NMR signal, the operator can determine whether a new first NMR signal has been received from the main resonant coil. Alternatively, the main control module 2 can continuously send field-locking signals multiple times at set time intervals, sweeping the frequency within a set range, and by observing the spectrum of the frequency domain NMR signal, the operator can determine whether a new second NMR signal has been received from the field-locking coil. If a new first or second NMR signal is received, it indicates that a new sample may have been used.

[0125] Furthermore, to avoid false detections caused by signal interference, the operator can receive a new first NMR signal at least twice consecutively through the main control module 2. By observing the spectrum of the frequency domain NMR signal, the operator can check whether both of the two consecutive new first NMR signals meet the preset signal indicators. If so, it indicates that the new first NMR signal is not an interference signal, and the frequency of the new first NMR signal can be used as the actual NMR signal frequency. If only one new first NMR signal is received, or if some of the signals in the two consecutive new first NMR signals do not meet the preset signal indicators, it indicates that a situation may have occurred where the original sample was removed but no new sample was placed in the sample. In this case, the NMR signal detection process needs to be stopped.

[0126] Similarly, to avoid false detections caused by signal interference, the operator can receive at least two new second NMR signals consecutively through the main control module 2. By observing the spectrum of the frequency domain NMR signal, the operator can check whether both of the two new second NMR signals received consecutively meet the preset signal indicators. If so, it indicates that the new second NMR signal is not an interference signal, and the actual NMR signal frequency of the first NMR signal can be determined based on the frequency of the new second NMR signal. If only one new second NMR signal is received, or if some of the signals in the two new second NMR signals received consecutively do not meet the preset signal indicators, it indicates that a situation may have occurred where the original sample was removed but no new sample was placed. In this case, the NMR signal detection process needs to be stopped.

[0127] In this embodiment of the invention, since the change in ambient temperature of the magnet module 3 and the change in frequency caused by changing the sample are very different, the main control module 2 mainly determines whether it is a temperature change or a sample change based on the rate of frequency change.

[0128] In one embodiment, reference is made to Figure 3 As shown, the above-mentioned quantum computing system also includes a field-locked resonant circuit 6, which includes a second varactor diode circuit (not shown in the figure). One end of the second varactor diode circuit is connected to the field-locked coil 5, and the other end is grounded.

[0129] Main control module 2 is connected to the second varactor diode circuit;

[0130] The main control module 2 is also used to send a second bias voltage signal to the second varactor diode circuit to adjust the resonant frequency of the field-locking coil 5 when quantum computing is not being performed.

[0131] In one specific embodiment, the field-locking resonant circuit 6 may further include a corresponding impedance matching capacitor (not shown in the figure). The specific structure of the field-locking resonant circuit 6 can be referred to the detailed description of the probe resonant circuit 1 described above. It should be noted that the specifications of the various electrical components in the field-locking resonant circuit 6 and the probe resonant circuit 1 described above may be different, and the sizes of the varactor diode circuit and the impedance matching capacitor in the two circuits can be selected according to actual needs.

[0132] In this embodiment of the invention, since the values ​​of the impedance matching capacitors in the field-locking coil 5 and the field-locking resonant circuit 6 are known, the frequency of the field-locking coil 5 is measured by continuously applying different bias voltage signals to the second varactor diode circuit. This yields a configured relationship between the resonant frequency of the field-locking coil and the bias voltage. This configured relationship between the resonant frequency of the field-locking coil and the bias voltage can be pre-built into the main control module 2 as a data table. When it is necessary to adjust the resonant frequency of the field-locking coil 5, the operator can determine the second bias voltage signal sent to the second varactor diode circuit based on the configured relationship between the resonant frequency of the field-locking coil and the bias voltage, thereby quickly adjusting the resonant frequency of the field-locking coil 5.

[0133] In one specific embodiment, the main resonant coil L1 and the field-locking coil 5 can share the same coil. In this case, the probe resonant circuit 1 and the field-locking resonant circuit 6 can be the same circuit, or the probe resonant circuit 1 and the field-locking resonant circuit 6 can be connected on both sides of the same coil. In some other embodiments, the main resonant coil L1 and the field-locking coil 5 can be different coils. In this case, the main resonant coil L1 and the field-locking coil 5 are arranged adjacent to each other, that is, the main resonant coil L1 and the field-locking coil 5 are arranged side by side in the magnetic field of the magnet module 3.

[0134] In one embodiment, reference is made to Figure 3 As shown, the above-mentioned quantum computing system also includes a control resonant circuit 8;

[0135] The control resonant circuit 8 includes a third varactor diode circuit (not shown in the figure), one end of which is connected to the control coil 7 and the other end is grounded;

[0136] Main control module 2 is connected to the third varactor diode circuit;

[0137] The main control module 2 is also used to send a third bias voltage signal to the third varactor diode circuit to adjust the resonant frequency of the control coil.

[0138] In one specific embodiment, the main resonant coil L1 and the control coil 7 can share the same coil; that is, the main resonant coil L1 serves as both a receiving coil and a transmitting coil. In this case, the probe resonant circuit 1 and the control resonant circuit 8 are the same circuit.

[0139] In one specific embodiment, the main resonant coil L1 and the control coil 7 can be two coils. Specifically, the main resonant coil L1 can be a helical coil, and the control coil 7 can be a cage coil. In this case, the probe resonant circuit 1 and the control resonant circuit 8 are different circuits. The control resonant circuit 8 may also include a corresponding impedance matching capacitor. The specific structure of the control resonant circuit 8 can be referred to in the detailed description of the probe resonant circuit 1. It should be noted that the specifications of the various electrical components in the control resonant circuit 8 and the probe resonant circuit 1 may be different, and the size of the varactor diode circuit and the impedance matching capacitor in the two circuits can be selected according to actual needs.

[0140] In this embodiment of the invention, since the values ​​of the impedance matching capacitors in the control coil 7 and the control resonant circuit 8 are known, the frequency of the control coil 7 is measured by continuously applying different bias voltage signals to the third varactor diode circuit. This yields a configured relationship between the resonant frequency of the control coil and the bias voltage. This configured relationship between the resonant frequency of the control coil and the bias voltage can be pre-built into the main control module 2 as a data table. When it is necessary to adjust the resonant frequency of the control coil 7, the operator can determine the third bias voltage signal to be sent to the third varactor diode circuit based on the configured relationship between the resonant frequency of the control coil and the bias voltage, thereby quickly adjusting the resonant frequency of the control coil 7.

[0141] In this embodiment of the present invention, the main resonant coil L1, the control coil 7, and the field-locking coil 5 can be implemented by the same coil or by multiple different coils.

[0142] For example, the main resonant coil L1, control coil 7, and field-locking coil 5 can share the same coil. Figure 3 (This is the illustrated case). In this case, the sample module 4 contains a mixed sample of a sample that serves as a quantum bit carrier and a sample used for locking the field. The mixed sample is placed in the middle of the shared coil. In other words, the shared coil is placed outside the mixed sample.

[0143] In one embodiment, the above-mentioned mixed sample is a mixed solution of dimethyl phosphite (or aqueous solution of phosphorous acid) and hexafluorobenzene, wherein dimethyl phosphite (or aqueous solution of phosphorous acid) is the sample used as a quantum bit carrier; and hexafluorobenzene is the sample used for field locking.

[0144] Optionally, in the mixed sample, the volume ratio of the above-mentioned dimethyl phosphite and hexafluorobenzene is 7:3.

[0145] In another embodiment, the above-mentioned mixed sample is a mixed solution of trifluoroiodide and acetone, wherein trifluoroiodide is the sample used as a quantum bit carrier; and acetone is the sample used for field locking.

[0146] Optionally, in the mixed sample, the volume ratio of trifluoroiodide (C2F3I) to acetone (C3H6O) is 7:3.

[0147] Understandably, different samples can be selected for different numbers of qubits, and this application does not impose any restrictions on this.

[0148] For example, the main resonant coil L1 and the control coil 7 share the same coil, while the field-locking coil 5 uses a different coil. Figure 3 (This situation is not illustrated). The coil shared by the control coil 7 and the main resonant coil L1 is arranged adjacent to the field-locking coil 5. Correspondingly, the sample for the qubit carrier and the sample for field locking in the sample module 4 are placed separately; the sample used as the qubit carrier is placed in the middle of the coil shared by the control coil 7 and the main resonant coil L1, and the sample used for field locking is placed in the middle of the field-locking coil 5.

[0149] In the above case, similarly, the sample used as the quantum bit carrier is dimethyl phosphite or an aqueous solution of phosphorous acid; correspondingly, the sample used for field locking is hexafluorobenzene.

[0150] For example, the sample used as the carrier of qubits is trifluoroiodide; the sample used for field locking is acetone.

[0151] This embodiment of the invention does not limit the specific sample used as the carrier of the qubit or the sample used as the shimming field; the above are merely specific examples.

[0152] Regardless of whether the main resonant coil L1, control coil 7, and field-locking coil 5 are set as the same coil or as multiple coils, the working periods of the signal transmission and reception of these coils are staggered, and there is a timing relationship between them.

[0153] For the field-locking coil 5, it operates during the periods when neither the control coil 7 nor the main resonant coil L1 is working. In other words, the field-locking coil 5 does not work when transmitting control signals and when using the main resonant coil L1 to detect the first NMR signal. The field-locking coil 5 only works when the system does not need to use the control coil 7 to transmit the radio frequency pulse corresponding to the control signal or use the main resonant coil L1 to detect the first NMR signal.

[0154] For control coil 7, it only operates when the system needs to transmit a control signal to transmit radio frequency pulses to excite the atomic nuclei that serve as qubits in the sample that act as qubit carriers.

[0155] For the main resonant coil L1, the first nuclear magnetic resonance signal (also a radio frequency signal) of the quantum bit is induced only after the control coil 7 has finished transmitting the control signal.

[0156] In one embodiment, when the main resonant coil L1, control coil 7, and field-locking coil 5 use the same coil, this method of sharing the same coil can realize the transmission and reception of multiple signals, while also having the advantages of simple and compact structure and higher integration.

[0157] In one embodiment, refer to Figure 6 As shown, there are two sets of probe resonant circuits 1, and the two sets of probe resonant circuits 1 are respectively connected to both sides of the main resonant coil L1.

[0158] The sample serving as a quantum bit carrier includes atomic nuclei at two different frequencies that also serve as quantum bits;

[0159] The main resonant coil L1 is specifically used to sense the two first nuclear magnetic signals when the atomic nuclei at two different frequencies that are quantum bits in the sample that serve as quantum bit carriers undergo nuclear magnetic resonance.

[0160] The main control module 2 connects to two first varactor diode circuits, DIODE1;

[0161] The main control module 2 is specifically used to send a first bias voltage signal to each of the two first varactor diode circuits DIODE1 to adjust the resonant frequency of the corresponding main resonant coil.

[0162] In this embodiment of the invention, considering that the sample serving as the quantum bit carrier may include two atomic nuclei at different frequencies that act as quantum bits, and that a single resonant circuit can only sense the nuclear magnetic resonance (NMR) signal of one atomic nucleus at any given time, the probe resonant circuit 1 can be configured as two sets to simultaneously sense the NMR signals of two atomic nuclei at different frequencies in order to achieve the sensing of NMR signals of two atomic nuclei at different frequencies. Since the atomic nuclei at different frequencies used as the quantum bit carrier and the atomic nuclei used as the locking field are always under the same magnetic field strength and temperature, the ratio of the NMR resonance frequency of each atomic nucleus to that of the atomic nucleus used as the locking field is fixed. Therefore, the main control module 2 can obtain the frequency domain NMR signal corresponding to the second NMR signal through a fast Fourier transform, determine the frequency of the second NMR signal based on the frequency of the frequency domain NMR signal, and the operator can calculate the actual NMR signal frequency of the first NMR signal sensed by the atomic nuclei at different frequencies based on the ratio of the resonance frequencies of the first NMR signal sensed by the atomic nuclei at different frequencies and the second NMR signal. Based on the pre-configured relationship between the resonant frequency and bias voltage of the main resonant coil, the operator can determine the first bias voltage to be sent to the two first varactor diode circuits, and then send the corresponding first bias voltage signal to the two first varactor diode circuits through the main control module 2, so as to quickly adjust the resonant frequency of the two sets of probe resonant circuits 1.

[0163] Taking dimethyl phosphite as an example, which serves as the carrier of qubits, Figure 7 The diagram shows the molecular structure of dimethyl phosphite (C2H7O3P). It reveals that the dimethyl phosphite molecule contains seven hydrogen (H) atoms and one phosphorus (P) atom. By setting up two sets of probe resonant circuits 1, and sending the corresponding bias voltage signals of the first varactor diode circuits DIODE1 of the two sets of probe resonant circuits 1 to sense hydrogen and phosphorus nuclei, the two resonant frequencies of the main resonant coil L1 are adjusted. Through the main resonant coil L1, the nuclear magnetic resonance signals of hydrogen and phosphorus nuclei can be sensed simultaneously.

[0164] Correspondingly, the number of the above-mentioned control resonant circuits 8 can also be two sets, with the two sets of control resonant circuits 8 respectively connected to both sides of the control coil 7;

[0165] The control coil 7 is used to transmit radio frequency pulses at frequencies corresponding to the two sets of control signals sent by the main control module 2.

[0166] Main control module 2 connects to two third varactor diode circuits;

[0167] The main control module 2 is specifically used to send two sets of control signals corresponding to the two different frequency atomic nuclei in the sample that serve as qubit carriers when performing quantum computing; and to send third bias voltage signals to the two third varactor diode circuits to adjust the resonant frequency of the corresponding control coils.

[0168] Of course, when the main resonant coil L1 and the control coil 7 use the same coil, the two sets of probe resonant circuits 1 and the two sets of control resonant circuits 8 are the same circuit.

[0169] In one embodiment, the aforementioned main control module 2, refer to Figure 3 As shown, it specifically includes: a programmable logic device 9, a digital-to-analog converter (DAC) 10, and an analog-to-digital converter (ADC) 11. The programmable logic device 9 is connected to both the DAC 10 and the ADC 11.

[0170] Programmable logic device 9 is used to modulate and generate control signals and field-locking signals, and to demodulate the second nuclear magnetic signal returned by field-locking coil 5 and the first nuclear magnetic signal returned by main resonant coil L1;

[0171] The aforementioned programmable logic device 9 can be a field programmable gate array (FPGA), a complex programmable logic device (CPLD), an erasable programmable logic device (EPLD), etc.

[0172] The digital-to-analog conversion module 10 is used to convert the control signal or field-locking signal into a digital-to-analog signal, and then into a corresponding analog signal for further transmission to the control coil 7 or the field-locking coil 5.

[0173] The programmable logic device 9 generates digital control signals and lock field signals, which can be converted into corresponding analog signals after digital-to-analog conversion.

[0174] The analog-to-digital conversion module 11 is used to convert the second nuclear magnetic signal returned by the field-locking coil 5 and the first nuclear magnetic signal returned by the main resonant coil L1 into analog-to-digital signals, convert them into corresponding digital signals, and send them to the programmable logic device 9.

[0175] The second nuclear magnetic signal returned by the field-locking coil 5 and the first nuclear magnetic signal returned by the main resonant coil L1 are analog signals. The analog-to-digital conversion module 11 converts them into corresponding digital signals and returns them to the programmable logic device 9.

[0176] The programmable logic device 9 generates modulated radio frequency signals (control signals and field-locking signals) that meet the requirements of quantum computing, and receives and demodulates radio frequency signals (first nuclear magnetic resonance signals and second nuclear magnetic resonance signals). In this embodiment of the invention, the modulation and demodulation of radio frequency signals are both implemented by the programmable logic device 9, without the need to add an additional hardware modem.

[0177] In order to control each quantum bit, the resonant radio frequency corresponding to each quantum bit is set in a different frequency band. Therefore, the programmable logic device 9 is required to generate multiple radio frequency signals (control signals) of different frequencies, and also needs to be able to receive and demodulate radio frequency signals (first nuclear magnetic resonance signals) of different frequencies.

[0178] Taking the selection of dimethyl phosphite as the physical bit carrier for quantum computing as an example, Figure 7 The diagram shows the molecular structure of dimethyl phosphite (C₂H₇O₃P). It reveals that the molecule contains seven hydrogen (H) atoms and one phosphorus (P) atom. The phosphorus nucleus is directly coupled to a hydrogen nucleus, and the nuclear magnetic moments of this phosphorus and coupled hydrogen nuclei can be used as the carriers of two physical bits for quantum computing. In other words, in a magnetic field, the phosphorus and hydrogen nuclei on the molecule split into two two-level systems due to Zeeman splitting, and each is used as a qubit.

[0179] By manipulating the directly coupled hydrogen and phosphorus nuclei with radio frequency electromagnetic waves, quantum computing gate operations can be performed using their nuclear magnetic moments, and their final states can be read (by sensing and demodulating the first nuclear magnetic signal).

[0180] For example, the fluorine nuclei in hexafluorobenzene (C6F6) or the hydrogen nuclei in acetone (C3H6O) in the sample used for field locking are excited by the radio frequency signal emitted by the field locking coil 5, and a second nuclear magnetic signal is induced by the field locking coil 5 and transmitted to the main control module 2 for demodulation.

[0181] The principle of field locking is to periodically excite the atomic nuclei used for field locking (such as the fluorine nuclei in hexafluorobenzene or the hydrogen nuclei in acetone) during the time without quantum computing, and read the state of the atomic nuclei used for field locking by sensing a second nuclear magnetic signal.

[0182] In sample module 4, regardless of whether the sample used as the qubit carrier and the sample used for locking the field are placed separately or together as a mixed sample, under the same magnetic field strength and temperature conditions, the ratio of the NMR frequency of the nuclei used as the qubit carrier to that used as the locking field remains constant. Therefore, regardless of changes in external temperature and magnetic field, since the nuclei used as the qubit carrier and the nuclei used as the locking field are always under the same magnetic field strength and temperature, the ratio of their NMR frequencies remains unchanged. For example, in a mixed solution of dimethyl phosphite and hexafluorobenzene, the ratio of the NMR frequencies of hydrogen nuclei to fluorine nuclei remains constant regardless of changes in external magnetic field strength and temperature. Similarly, the ratio of the NMR frequencies of phosphorus nuclei to fluorine nuclei does not change.

[0183] However, in quantum computing systems, the magnetic field strength of magnet module 3 is sensitive to temperature. Changes in external temperature may lead to changes in magnetic field strength, which in turn will cause changes in the nuclear magnetic resonance frequencies of the atomic nuclei used as qubit carriers and the atomic nuclei used as lock fields (although the ratio between the two does not change).

[0184] Based on the above principles, the field-locking signal and the second NMR signal can be used to calibrate the frequency of the future transmitted control signal and the actual NMR signal frequency of the first NMR signal. The frequency of the control signal manipulating the same atomic nucleus is the same as the actual NMR signal frequency of the corresponding first NMR signal.

[0185] When quantum computing is not performed, the lock field signal is sent periodically. The programmable logic device 9 in the main control module 2 demodulates the second nuclear magnetic resonance signal that is sensed back. The latest frequency value of the lock field signal obtained by periodically sending the lock field signal is saved so that when a control signal needs to be sent, the latest frequency value corresponding to the first nuclear magnetic resonance signal and the control signal can be calculated based on this latest frequency value.

[0186] In one embodiment, the above-described quantum computing system, referring to Figure 3 As shown, it also includes: at least one first RF switch 14, at least one channel control signal processing module 12, and at least one channel first broadband RF amplification module 13 corresponding to the at least one channel control signal processing module 12; wherein:

[0187] Each control signal processing module 12 and its corresponding first broadband radio frequency amplification module 13 are respectively connected to a first radio frequency switch 14 and switch operation through the first radio frequency switch 14;

[0188] At least one channel of the control signal processing module 12 and at least one first radio frequency switch 14 are connected between the digital-to-analog converter module 10 of the main control module 2 and the control resonant circuit 8;

[0189] At least one channel of the first broadband RF amplifier module 13 and at least one first RF switch 14 are connected between the analog-to-digital converter module 11 of the main control module 2 and the probe resonant circuit 1;

[0190] The first RF switch 14 conducts the control coil 7, the control resonant circuit 8, the control signal processing module 12, and the main control module 2 when the control signal is transmitted; when the control signal is turned off and the non-locked field signal is transmitted, the main resonant coil L1, the probe resonant circuit 1, the first broadband RF amplification module 13, and the main control module 2 are conducted.

[0191] The first RF switch 14 is responsible for switching between the control signal processing module 12 and the first broadband RF amplification module 13.

[0192] The reason why the control signal processing module 12 has multiple channels is that there are multiple atomic nuclei in the sample that serve as qubit carriers, and each needs to be processed by a separate control signal processing module 12. For example, in the case of the mixed sample of dimethyl phosphite and hexafluorobenzene, the phosphorus nucleus and the hydrogen nucleus are used as two qubits respectively. In this case, two different control signal processing modules 12 can be set up to process the control signals of different qubits respectively (the frequencies of the control signals are different from each other).

[0193] In one embodiment, when control signals of different frequencies are sent sequentially, the multiple control signal processing modules 12 of different channels can be implemented using a single channel. Correspondingly, the multiple first broadband RF amplification modules 13 of different channels can also be implemented using a single channel. That is, control signals of different frequencies are processed through the same channel control signal processing module 12, and correspondingly, first NMR signals of different frequencies (the control signals and the corresponding first NMR signals have the same frequency) can also be processed through the same channel first broadband RF amplification module 13.

[0194] Furthermore, the aforementioned control signal processing module 12 specifically includes: a power amplifier circuit 15; the power amplifier circuit 15 is used to amplify the control signals sent by the main control module 2;

[0195] The power amplifier circuit 15 is responsible for amplifying the control signal to a suitable intensity. In this embodiment of the invention, the power amplifier circuit 15 may have a gain of 56dB and a maximum power of 50W in the range of 10-60MHz.

[0196] In one embodiment, a filter circuit may also be provided on the control signal processing module 12. Figure 3(Not shown in the diagram) If a filtering circuit is required, it should be placed before the power amplifier circuit 15 (i.e., the control signal should be filtered before amplification). Alternatively, if the power amplifier circuit 15 is a multi-stage amplifier circuit, the filtering circuit can be placed between the multi-stage amplifier circuits, for example, between two stages of amplifier circuits.

[0197] Correspondingly, the first broadband radio frequency amplification module 13 includes: a first broadband filter circuit 16 and a first low noise amplifier circuit 17;

[0198] The first broadband filter circuit 16 is used to filter the first nuclear magnetic signal induced by the main resonant coil L1;

[0199] The first low-noise amplifier circuit 17 is used to amplify the filtered first nuclear magnetic resonance signal.

[0200] In one embodiment, the first broadband filtering circuit 16 is a broadband filter.

[0201] In one embodiment, the first broadband filter circuit 16 and the first radio frequency switch 14 are integrated into the same module.

[0202] In one embodiment, the above-described quantum computing system, referring to Figure 3 As shown, it may also include: a field-locking signal transmitting module 18, a second broadband radio frequency amplifier module 19, and a second radio frequency switch 20;

[0203] The field-locking signal transmitting module 18 and the second broadband radio frequency amplification module 19 are respectively connected to the second radio frequency switch 20, and are switched to work by the second radio frequency switch 20;

[0204] The field-locking signal transmitting module 18 and the second radio frequency switch 20 are connected between the digital-to-analog converter module 10 of the main control module 2 and the field-locking resonant circuit 6;

[0205] Correspondingly, the second broadband RF amplifier module 19 and the second RF switch 20 are connected between the analog-to-digital converter module 11 and the field-locked resonant circuit 6 of the main control module 2.

[0206] In one embodiment, since the transmitted field lock signal does not need to be as high quality as the control signal, the field lock signal transmitting module 18 may not be equipped with any functional circuits (no filtering or amplification, etc.), and may only serve the purpose of transmitting the field lock signal.

[0207] Of course, in an optional embodiment, the above-mentioned field signal transmission module 18 can also be equipped with functional circuits such as filtering circuits and amplification circuits, which are similar in structure to the aforementioned control signal processing module 12, and will not be described in detail here.

[0208] The second RF switch 20 is responsible for switching between the field lock signal transmitting module 18 and the second broadband RF amplification module 19. First, the field lock signal is transmitted. After the transmission is completed, it switches to the second broadband RF amplification module 19, so that the second nuclear magnetic signal induced by the field lock coil 5 can be successfully processed by the second broadband RF amplification module 19 and returned to the main control module 2.

[0209] In one embodiment, the second broadband RF amplifier module 19 specifically includes: a second broadband filter circuit 21 and a second low-noise amplifier circuit 22;

[0210] The second broadband filter circuit 21 is used to filter the second nuclear magnetic signal induced by the field-locking coil 5;

[0211] The second low-noise amplifier circuit 22 is used to amplify the filtered second nuclear magnetic resonance signal.

[0212] In one embodiment, the second broadband filtering circuit 21 is a broadband filter.

[0213] The second broadband filter circuit 21 functions similarly to the first broadband filter circuit 16, and the second low-noise amplifier circuit 22 functions similarly to the first low-noise amplifier circuit 17, so they will not be described again here.

[0214] In one embodiment, the second broadband filter circuit 21 and the second radio frequency switch 20 are integrated into the same module.

[0215] In one embodiment, the field-locking signal transmitting module 18 and one of the multiple channels of the control signal processing module 12 can be configured as the same circuit;

[0216] Accordingly, the second broadband RF amplifier module 19 and one of the multiple channels of the first broadband RF amplifier module 13 can also be configured as the same circuit.

[0217] In one embodiment, refer to Figure 3 As shown, the quantum computing system also includes a power supply module 23; the main control module 2 also includes a power management module 24.

[0218] The power management module 24 is used to control the power module 23 to output a corresponding bias voltage signal based on a determined bias voltage. The determined bias voltage may include the first bias voltage, the second bias voltage, and the third bias voltage mentioned above, and the corresponding bias voltage signal may include the first bias voltage signal, the second bias voltage signal, and the third bias voltage signal mentioned above.

[0219] In this embodiment of the invention, the magnitude of the output bias voltage signal can be precisely controlled by the power management module 24 to achieve resonant frequency adjustment, so that the resonant frequency of the probe resonant circuit 1 is precisely matched with the actual frequency of the nuclear magnetic resonance signal.

[0220] In one embodiment, refer to Figure 3 As shown, optionally, the above-mentioned quantum computing system may also include, for example, a temperature detection module 25;

[0221] The temperature detection module 25 is connected to the main control module 2 and is located in the magnet module 3. It is used to detect the temperature of the magnet module 3 and send the temperature signal to the main control module 2.

[0222] The main control module 2 is also used to determine whether the temperature of the magnet module 3 has changed based on the received temperature signal.

[0223] In this embodiment of the invention, by setting a temperature detection module 25 to detect the temperature of the magnet module 3, it is possible to verify whether the temperature of the magnet module 3 has actually changed.

[0224] In one embodiment, reference is made to Figure 3 As shown, the existing temperature control module 26 can also be retained to keep the magnet module 3 at a very stable temperature. The temperature control module is used to control the temperature of the magnet module 3 based on the temperature returned by the temperature detection module 25, and to maintain the temperature of the magnet module 3 at the set temperature.

[0225] In one embodiment, the magnet module 3 includes two permanent magnet modules 3 and a magnetic yoke disposed on the permanent magnet module 3; by finely adjusting the structure of the permanent magnet module 3, a highly uniform magnetic field can be generated, with a magnetic field strength of, for example, 1 Tesla and a uniformity of, for example, 10 ppm (within a range of 5 mm in both diameter and height).

[0226] In one embodiment, refer to Figure 3 As shown, the quantum computing system described above may further include: a shimming current source 28 and at least one set of shimming coils 27 electrically connected to the shimming current source 28; the shimming coils 27 are disposed between two permanent magnet modules 3, and the shimming coils 27 are used to actively shimmy the magnetic field generated by the magnet modules 3.

[0227] Due to factors such as processing precision, the magnetic field uniformity produced by the permanent magnet module 3 is not yet able to meet the requirements of quantum computing (even if these permanent magnet modules 3 have undergone very careful passive shimming). Therefore, it is necessary to use shimming coils 27 of different shapes with current to generate a compensating magnetic field in order to achieve superposition with the magnetic field of the permanent magnet module 3 and finally obtain a magnetic field with higher uniformity.

[0228] Reference Figure 3As shown, there are multiple sets of shimming coils 27, each set of shimming coils 27 is symmetrically arranged inside the two permanent magnet modules 3. For example, there are 12 sets of shimming coils 27, and the magnitude of the current in the shimming coils 27 can be controlled by the main control module 2.

[0229] The quantum computing system and nuclear magnetic resonance quantum computer provided in this embodiment of the invention, by setting a main resonant coil L1 and a varactor diode circuit in the probe resonant circuit 1, allows the main resonant coil L1 to sense the first nuclear magnetic resonance signal when the atomic nuclei of the sample, which serve as the carrier of the qubits, undergo nuclear magnetic resonance. When it is necessary to adjust the resonant frequency of the resonant circuit, the main control module 2 sends a corresponding bias voltage signal to change the capacitance value of the varactor diode circuit, thus achieving simple and efficient resonant frequency adjustment. In this scheme, the bias voltage is determined based on the pre-configured relationship between the resonant frequency and the bias voltage. The main control module 2 sends a bias voltage signal to change the capacitance value of the varactor diode circuit, achieving rapid adjustment of the frequency point of the resonant circuit to the optimal frequency point of the corresponding sample. The frequency adjustment speed can reach the nanosecond level, and the frequency adjustment accuracy can reach 0.01MHz, greatly improving the detection efficiency and accuracy of the nuclear magnetic resonance signal, and enhancing the quantum computing efficiency of the quantum computing system.

[0230] The quantum computing system and nuclear magnetic resonance quantum computer provided in this embodiment of the invention, compared with the prior art of changing the capacitance value in the circuit through manual mechanical adjustment mechanisms, adopt an electronic tuning method based on varactor diode circuits and bias voltage. This not only increases the frequency adjustment range, making it adaptable to most nuclear magnetic resonance detection scenarios, including high-frequency bands, but also avoids the electromagnetic interference problems caused by mechanical adjustment mechanisms. Compared with traditional methods of manually soldering other capacitors or mechanically adjusting capacitors, the varactor diode circuit allows for a reduction in probe size, resulting in a more compact structure, higher integration, and smaller footprint for the quantum computing system. Furthermore, the electronic tuning method facilitates intelligent control using standardized digital intelligent control interfaces, making it easy to integrate with modern detection systems.

[0231] To better illustrate the structure and function of each part of the quantum computing system provided in the embodiments of this utility model, several specific embodiments are described below.

[0232] Example 1:

[0233] The structure of Embodiment 1 of this utility model can be referred to Figure 8 As shown, the quantum computing system includes: a magnet module ( Figure 8 (not shown in the image), sample module ( Figure 8 (not shown in the image), power module ( Figure 8 (not shown in the image), power management module ( Figure 8(not shown in the image), temperature detection module ( Figure 8 (not shown in the image), temperature control module ( Figure 8 (not shown in the image), uniform current source and uniform coil (in...) Figure 8 (Not shown in the diagram) Main control module, main resonant coil, control coil and field-locking coil, control signal processing module, first broadband RF amplification module, first RF switch, field-locking signal transmission module, second broadband RF amplification module, second RF switch, probe resonant circuit, control resonant circuit and field-locking resonant circuit, etc., wherein the main resonant coil, control coil and field-locking coil are the same coil. The structure and function of magnet module, sample module, shimming current source and shimming coil are the same as in the previous embodiment, and will not be repeated here. The following describes... Figure 8 Each module shown in the diagram will be explained.

[0234] In Example 1, the sample module contains a mixed sample, which is a mixed solution of dimethyl phosphite (C2H7O3P) and hexafluorobenzene (C6F6). The hydrogen (H) and phosphorus (P) nuclei in the dimethyl phosphite serve as the carriers of the qubits, while the fluorine nuclei in the hexafluorobenzene serve as the field-locking nuclei.

[0235] The frequency of the control signal that manipulates the hydrogen nucleus is the same as the frequency of the corresponding first NMR signal. Similarly, the frequency of the control signal that manipulates the phosphorus nucleus is the same as the frequency of the corresponding first NMR signal. However, the frequency of the control signal that manipulates the hydrogen nucleus is not the same as the frequency of the control signal that manipulates the phosphorus nucleus.

[0236] The frequency of the lock field signal that controls the fluorine nucleus is different from the frequency of the control signals that control the hydrogen and phosphorus nuclei, but the frequency of the lock field signal is the same as the frequency of the corresponding second nuclear magnetic resonance signal.

[0237] exist Figure 8 In this system, the letter H represents the hydrogen nucleus, the letter P represents the phosphorus nucleus, and the letter F represents the fluorine nucleus.

[0238] The main control module includes a programmable logic device (FPGA) and a digital-to-analog converter (DAC) and an analog-to-digital converter (ADC) connected to the FPGA.

[0239] The DAC has two outputs, corresponding to the control signal processing module (including the power amplifier circuit) and the field lock signal transmission module, respectively.

[0240] The control signal processing module is equipped with a power amplifier circuit;

[0241] The field-locking signal transmission module is connected between the DAC and the second RF switch.

[0242] The ADC has two inputs: one from the second NMR signal processing module (including low-noise amplification and wideband filtering circuits), and the other from either of the two first NMR signal processing modules (each channel includes low-noise amplification and wideband filtering circuits). These two first NMR signal processing modules are used to process the first NMR signals returned by the excitation of hydrogen and phosphorus nuclei, respectively. Since the first NMR signals corresponding to hydrogen nuclei and phosphorus nuclei are not generated simultaneously, only the first NMR signal from one of the channels will return to the main control module at any given time. Therefore, the two first NMR signal processing modules can share the same input channel of the ADC. Figure 8 In the diagram, the first nuclear magnetic resonance signal processing module for the two channels is labeled as: First Nuclear Magnetic Resonance Signal Processing Module (H&P).

[0243] In Example 1, the control signals corresponding to the hydrogen nuclei and the phosphorus nuclei share the same control signal processing module. Figure 8 The label indicates: Control Signal Processing Module (H&P). On the one hand, the transmission of control signals for hydrogen and phosphorus nuclei is time-division multiplexing (for example, hydrogen nuclei are excited first, then phosphorus nuclei are excited, there is a sequence), and they will not occur simultaneously. On the other hand, because the bandwidth of the power amplifier circuit is relatively wide, although the frequencies of the control signals for hydrogen and phosphorus nuclei are different, they can share the same power amplifier circuit.

[0244] In Example 1, the control signals and the first NMR signal for hydrogen and phosphorus nuclei are processed by the same probe resonant circuit (the control resonant circuit and the probe resonant circuit are the same circuit and are therefore not shown separately), while the field-locking signal and the second NMR signal for fluorine nuclei are processed by the field-locking resonant circuit.

[0245] Example 2:

[0246] The structure of Embodiment 2 of this utility model can be referred to Figure 9 As shown, the quantum computing system includes: a magnet module ( Figure 9 (not shown in the image), sample module ( Figure 9 (not shown in the image), power module ( Figure 9 (not shown in the image), power management module ( Figure 9 (not shown in the image), temperature detection module ( Figure 9 (not shown in the image), temperature control module ( Figure 9 (not shown in the image), uniform current source and uniform coil (in...) Figure 9(Not shown in the diagram) The main control module, main resonant coil, control coil and field-locking coil, control signal processing module, first broadband RF amplification module, first RF switch, field-locking signal transmission module, second broadband RF amplification module, second RF switch, probe resonant circuit, control resonant circuit and field-locking resonant circuit, etc., wherein the main resonant coil, control coil and field-locking coil are the same coil. The structure and function of the magnet module, sample module, shimming current source and shimming coil are the same as in the previous embodiment, and will not be repeated here. The following describes... Figure 9 Each module shown in the diagram will be explained.

[0247] In Example 2, similar to Example 1, the mixed sample contained in the sample module was also a mixed solution of dimethyl phosphite (C2H7O3P) and hexafluorobenzene (C6F6). Figure 9 In this system, the letter H represents the hydrogen nucleus, the letter P represents the phosphorus nucleus, and the letter F represents the fluorine nucleus.

[0248] Unlike Example 1, in Example 2, the field-locking signal transmission module corresponding to the fluorine nucleus and the control signal processing module corresponding to the hydrogen nucleus share the same circuit. Figure 9 The module is designated as the control signal processing module and the field-locking signal transmission module; the second broadband RF amplification module corresponding to the fluorine nucleus shares the same circuit implementation as the first broadband RF amplification module corresponding to the hydrogen nucleus. Figure 9 The designations are: First Wideband RF Amplifier Module (H) & Second Wideband RF Amplifier Module (F), see reference. Figure 9 As shown, the circuit includes a low-noise amplification and broadband filtering circuit.

[0249] The control signal processing module for the phosphorus nucleus and the first broadband radio frequency amplification module are set separately from the signal processing circuits for the aforementioned fluorine and hydrogen nuclei.

[0250] When the control signal processing module corresponding to the hydrogen nucleus and the field-locking signal transmission module corresponding to the fluorine nucleus share the same circuit, refer to... Figure 9 As shown, the circuit includes a power amplifier circuit.

[0251] The specific structures of the first broadband RF amplification module and the second broadband RF amplification module are similar to those in the aforementioned embodiment 1, and will not be described again here.

[0252] Since the field-locking signal corresponding to the fluorine nucleus and the control signal corresponding to the hydrogen nucleus also have different timing sequences and will not be generated and transmitted simultaneously, the control signal processing module 12 corresponding to the hydrogen nucleus and the field-locking signal transmitting module corresponding to the fluorine nucleus can share the same circuit.

[0253] The first radio frequency switch is used to switch the transmission of the phosphorus nucleus control signal and the reception of the first nuclear magnetic signal of the phosphorus nucleus.

[0254] The second radio frequency switch is used to switch the transmission of the hydrogen nucleus control signal and the reception of the first nuclear magnetic resonance signal of the hydrogen nucleus; and to switch the transmission of the fluorine nucleus lock field signal and the reception of the second nuclear magnetic resonance signal of the fluorine nucleus.

[0255] In Example 2, two resonant circuits were also used to process the radio frequency signals of phosphorus nuclei and the radio frequency signals of hydrogen and fluorine nuclei, respectively.

[0256] Example 3:

[0257] The structure of Embodiment 3 of this utility model can be referred to Figure 10 As shown, the quantum computing system includes: a magnet module ( Figure 10 (not shown in the image), sample module ( Figure 10 (not shown in the image), power module ( Figure 10 (not shown in the image), power management module ( Figure 10 (not shown in the image), temperature detection module ( Figure 10 (not shown in the image), temperature control module ( Figure 10 (not shown in the image), uniform current source and uniform coil (in...) Figure 10 (Not shown in the diagram) The main control module, main resonant coil, control coil and field-locking coil, control signal processing module, first broadband RF amplification module, first RF switch, field-locking signal transmission module, second broadband RF amplification module, second RF switch (which is the same device as the first RF switch 14, so it is not shown separately), probe resonant circuit, control resonant circuit and field-locking resonant circuit, etc. Among them, the main resonant coil, control coil and field-locking coil are the same coil. The structure and function of the magnet module, sample module, shimming current source and shimming coil are the same as those in the previous embodiment, and will not be repeated here.

[0258] Unlike Embodiments 1 and 2, all channels' control signal processing modules and field lock signal transmission modules utilize the same circuit implementation. Figure 10 The diagram only illustrates the structure of the control signal processing module for one channel, labeled: Control Signal Processing Module (F) & Lock Signal Transmission Module (H). This circuit includes a power amplifier circuit. Furthermore, since the first and second broadband RF amplifier modules for multiple channels are also implemented using the same circuit, Figure 10 The diagram only shows the structure of the first broadband RF amplifier module with one channel, labeled as: First Broadband RF Amplifier Module (F) & Second Broadband RF Amplifier Module (H). This circuit includes low-noise amplification and broadband filtering circuits.

[0259] Furthermore, the functions of the first and second RF switches are implemented using the same RF switch. Figure 10 Only the first radio frequency switch is shown in the diagram.

[0260] In Example 3, the functions of the probe resonant circuit, control resonant circuit, and field-locking resonant circuit are also implemented using the same circuit. Therefore, Figure 10 Only the probe resonant circuit is shown in the diagram (the control resonant circuit and the field-locking resonant circuit are the same circuit as the probe resonant circuit, so they are not shown separately). One end of the probe resonant circuit is grounded.

[0261] Unlike Examples 1 and 2, the sample module in Example 3 contained a mixed sample solution of trifluoroiodide (C2F3I) and acetone (C3H6O). In a magnetic field, the three fluorine nuclei on the trifluoroiodide molecule split into three two-level systems due to Zeeman splitting, which were then used as three qubits. The hydrogen atoms on the acetone were used for field locking. Figure 10 In this context, the letter H represents the hydrogen nucleus, and the letter F represents the fluorine nucleus.

[0262] Whether it is trifluoroiodide as the control signal of the three fluorine atoms of the three qubits, or the field-locking signal of the hydrogen atoms on acetone, their transmission timing is separate. Similarly, the reception timing of the first NMR signal of the three fluorine atoms and the second NMR signal corresponding to the hydrogen atoms is also separate.

[0263] In Example 3, from Figure 10 As can be seen, the ADC has only one input and the DAC has only one output.

[0264] Compared with Examples 1 and 2, Example 3 has higher hardware integration, a more compact structure, lower hardware cost, and is more conducive to the miniaturization of the overall system.

[0265] Based on the same inventive concept, this utility model also provides a nuclear magnetic resonance quantum computer, referring to... Figure 11 As shown, it includes: a quantum computing host 200 and a quantum computing system 100 as provided in the foregoing embodiments;

[0266] The quantum computing host 200 is communicatively connected to the main control module 2 of the quantum computing system 100.

[0267] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A quantum computing system, characterized in that, include: Main resonant coil, probe resonant circuit, main control module, magnet module and sample module; The probe resonant circuit includes a first varactor diode circuit, one end of which is connected to the main resonant coil and the other end is grounded. The sample module contains a sample serving as a quantum bit carrier; the sample serving as a quantum bit carrier is placed in the magnetic field of the magnet module. The main resonant coil is disposed in the magnetic field of the magnet module, connected to the main control module, and positioned between the main control module and the sample module; The main resonant coil is used to sense the first nuclear magnetic signal when the atomic nuclei that serve as qubits in the sample that serve as qubit carriers undergo nuclear magnetic resonance. The main control module is connected to the first varactor diode circuit; The main control module is used to send a first bias voltage signal to the first varactor diode circuit to adjust the resonant frequency of the main resonant coil.

2. The quantum computing system as described in claim 1, characterized in that, It also includes control coils and field-locking coils; The sample module also contains a sample for field locking; the sample for field locking is placed in the magnetic field of the magnet module. The control coil and the field-locking coil are disposed in the magnetic field of the magnet module, connected to the main control module, and positioned between the main control module and the sample module; The control coil is used to transmit radio frequency pulses of at least one frequency corresponding to the control signal sent by the main control module. The field-locking coil is used to transmit radio frequency pulses of at least one frequency corresponding to the field-locking signal according to the field-locking signal sent by the main control module, and to sense a second nuclear magnetic signal when nuclear magnetic resonance occurs between the atomic nuclei used for field-locking in the sample. The main control module is also used to send the locking signal to the locking coil and receive and demodulate the second nuclear magnetic resonance signal corresponding to the locking signal when not performing quantum computing; and to send the control signal to the control coil and receive and demodulate the first nuclear magnetic resonance signal corresponding to the control signal when performing quantum computing.

3. The quantum computing system as described in claim 2, characterized in that, It also includes a field-locking resonant circuit, which includes a second varactor diode circuit, one end of which is connected to the field-locking coil and the other end is grounded. The main control module is connected to the second varactor diode circuit; The main control module is also used to send a second bias voltage signal to the second varactor diode circuit to adjust the resonant frequency of the field-locking coil when not performing quantum computing, so as to adjust the resonant frequency of the field-locking coil.

4. The quantum computing system as described in claim 3, characterized in that, The main resonant coil and the field-locking coil share the same coil; the probe resonant circuit and the field-locking resonant circuit are the same circuit, or the probe resonant circuit and the field-locking resonant circuit are connected on both sides of the same coil; or, The main resonant coil and the field-locking coil are arranged adjacent to each other.

5. The quantum computing system as described in claim 4, characterized in that, It also includes a control resonant circuit, which includes a third varactor diode circuit, one end of which is connected to the control coil and the other end is grounded. The main control module is connected to the third varactor diode circuit; The main control module is also used to send a third bias voltage signal to the third varactor diode circuit to adjust the resonant frequency of the control coil, so as to adjust the resonant frequency of the control coil.

6. The quantum computing system as described in claim 5, characterized in that, The main resonant coil is a helical coil, and the control coil is a cage coil; Alternatively, the main resonant coil and the control coil share the same coil; the probe resonant circuit and the control resonant circuit are the same circuit.

7. The quantum computing system as described in claim 5, characterized in that, The probe resonant circuit consists of two sets, which are respectively connected to both sides of the main resonant coil. The sample serving as the carrier of qubits includes atomic nuclei at two different frequencies that serve as qubits. The main resonant coil is specifically used to sense two first nuclear magnetic signals when the atomic nuclei at two different frequencies that serve as quantum bits in the sample that are quantum bit carriers undergo nuclear magnetic resonance. The main control module is connected to two of the first varactor diode circuits; The main control module is specifically used to send a first bias voltage signal to each of the two first varactor diode circuits to adjust the resonant frequency of the corresponding main resonant coil.

8. The quantum computing system as described in claim 7, characterized in that, The number of control resonant circuits is two sets, and the two sets of control resonant circuits are respectively connected to both sides of the control coil; The control coil is used to transmit radio frequency pulses at frequencies corresponding to the two sets of control signals sent by the main control module. The main control module is connected to the two third varactor diode circuits; Specifically, when performing quantum computing, the main control module sends two sets of control signals corresponding to the two different frequency atomic nuclei in the sample that serve as qubit carriers; and sends third bias voltage signals to the two third varactor diode circuits to adjust the resonant frequency of the corresponding control coils.

9. The quantum computing system as described in claim 5, characterized in that, The main control module includes: a programmable logic device, a digital-to-analog converter (DAC), and an analog-to-digital converter (ADC), wherein the programmable logic device is connected to both the DAC and the ADC; wherein: The programmable logic device is used to modulate and generate the control signal and the field-locking signal, and to demodulate the second nuclear magnetic signal returned by the field-locking coil and the first nuclear magnetic signal returned by the main resonant coil; The digital-to-analog conversion module is used to convert the control signal or field-locking signal into a digital-to-analog signal, and then into a corresponding analog signal, so as to send it to the control coil or the field-locking coil. The analog-to-digital conversion module is used to convert the second nuclear magnetic resonance signal returned by the field-locking coil and the first nuclear magnetic resonance signal returned by the main resonant coil into analog-to-digital signals, convert them into corresponding digital signals, and send them to the programmable logic device.

10. The quantum computing system as described in claim 9, characterized in that, Also includes: At least one first radio frequency switch, at least one channel control signal processing module, and at least one channel first broadband radio frequency amplification module corresponding to the at least one channel control signal processing module; Each control signal processing module and its corresponding first broadband RF amplification module are connected to a first RF switch and switch operation via the first RF switch; At least one channel of the control signal processing module and the at least one first radio frequency switch are connected between the digital-to-analog converter module of the main control module and the control resonant circuit; At least one channel of the first broadband RF amplifier module and at least one first RF switch are connected between the analog-to-digital conversion module of the main control module and the probe resonant circuit; The first radio frequency switch conducts the control coil, control resonant circuit, control signal processing module, and main control module when the control signal is transmitted; and conducts the main resonant coil, probe resonant circuit, first broadband radio frequency amplification module, and main control module when the control signal is turned off and a non-locked field signal is transmitted.

11. The quantum computing system as described in claim 10, characterized in that, The first broadband radio frequency amplification module includes: a first broadband filter circuit and a first low-noise amplification circuit; The first broadband filter circuit is used to filter the first nuclear magnetic signal induced by the main resonant coil; The first low-noise amplifier circuit is used to amplify the filtered first nuclear magnetic resonance signal.

12. The quantum computing system as described in claim 11, characterized in that, The first broadband filtering circuit is a broadband filter.

13. The quantum computing system as described in claim 10, characterized in that, The control signal processing module includes a power amplifier circuit; the power amplifier circuit is used to amplify the control signal sent by the main control module.

14. The quantum computing system as described in claim 10, characterized in that, Also includes: Lock field signal transmitting module, second broadband RF amplifier module, and second RF switch; The field-locking signal transmitting module and the second broadband radio frequency amplification module are respectively connected to the second radio frequency switch, and their operation is switched through the second radio frequency switch; The field-locking signal transmitting module and the second radio frequency switch are connected between the digital-to-analog converter module of the main control module and the field-locking resonant circuit; The second broadband RF amplifier module and the second RF switch are connected between the analog-to-digital converter module of the main control module and the field-locked resonant circuit.

15. The quantum computing system as described in claim 14, characterized in that, The second broadband radio frequency amplification module includes: a second broadband filter circuit and a second low-noise amplification circuit; The second broadband filter circuit is used to filter the second nuclear magnetic signal induced by the field-locking coil; The second low-noise amplifier circuit is used to amplify the filtered second nuclear magnetic resonance signal.

16. The quantum computing system as described in claim 15, characterized in that, The second broadband filtering circuit is a broadband filter.

17. The quantum computing system as described in claim 14, characterized in that, The field-locking signal transmitting module and one channel of the multiple-channel control signal processing module are configured to share the same circuit; The second broadband RF amplifier module and one channel of the first broadband RF amplifier module with multiple channels are configured to share the same circuit.

18. The quantum computing system as described in claim 14, characterized in that, The field-locking signal transmitting module and the control signal processing modules for all channels are configured to use the same circuit; The second broadband RF amplifier module and the first broadband RF amplifier module for all channels are configured to use the same circuit.

19. The quantum computing system according to any one of claims 1-18, characterized in that, The varactor diode circuit includes a distributed varactor diode array, or at least one varactor diode and at least one fixed capacitor connected in parallel.

20. The quantum computing system as described in claim 19, characterized in that, The probe resonant circuit also includes an impedance matching capacitor. The main resonant coil is connected in series with the impedance matching capacitor.

21. The quantum computing system according to any one of claims 1-18, characterized in that, It also includes a power module; The main control module also includes a power management module; The power management module is used to control the power module to output a corresponding bias voltage signal based on a determined bias voltage.

22. The quantum computing system according to any one of claims 1-18, characterized in that, Also includes: Temperature detection module; The temperature detection module is connected to the main control module and is located on the magnet module. It is used to detect the temperature of the magnet module and send the temperature signal to the main control module. The main control module is also used to determine whether the temperature of the magnet module has changed based on the received temperature signal.

23. A nuclear magnetic resonance quantum computer, characterized in that, include: A quantum computing host and a quantum computing system as described in any one of claims 1-22; The quantum computing host is communicatively connected to the main control module of the quantum computing system.

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