Quantum computing system and nuclear magnetic resonance quantum computer

Abstract

The utility model discloses a quantum computing system, which is characterized by comprising a magnet, a sample module, a main control board, a probe, a control coil, a field locking coil, a shimming current source and at least one group of shimming coils, the sample module is provided with a sample used as a quantum bit carrier and a sample used for field locking; the control coil is used for transmitting radio frequency pulses of at least one frequency according to the control signal; the probe is used for sensing a first nuclear magnetic signal; the field locking coil is used for transmitting a radio frequency pulse for calibrating the frequency of a control signal according to the field locking signal and sensing a second nuclear magnetic signal; the main control board is used for sending a field locking signal when quantum calculation is not carried out, demodulating a second nuclear magnetic signal, calibrating the frequency of a control signal and storing the frequency; and generating and sending a control signal according to the frequency of the newly calibrated control signal, and receiving and demodulating a first nuclear magnetic signal returned by the probe. According to the quantum computing system, the computing efficiency of the quantum computing system is improved, the structure is more compact, the integration degree is higher, and the occupied space is smaller.

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, quantum computing systems rely on various physical experimental platforms, such as nuclear magnetic resonance (NMR), superconducting quantum chips, ion traps, and photonic quantum computing. Among these, NMR is the earliest developed, most mature, and most widely used quantum computing system for implementing quantum algorithms. Quantum computing systems implemented with NMR can realize a wide range of quantum computing algorithms at room temperature and pressure, have mature radio frequency 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] If all atomic nuclei are to exhibit the same resonance properties, the nuclear magnetic resonance quantum computing experimental platform needs to have an extremely stable and uniform magnetic field.

[0005] In existing technologies, when a nuclear magnetic resonance quantum computer uses a magnet (such as a superconducting coil) as a magnetic field source to perform quantum computing in a nuclear magnetic resonance system, it requires a high degree of stability of the magnetic field. In order to avoid the influence of temperature fluctuations on the magnetic field strength, very stable temperature control is required to keep the temperature drift within a very small range.

[0006] The typical solution involves using a complex temperature control module to regulate the magnet's temperature and ensure stable NMR signal frequency. For example, the temperature control module maintains the magnet at a very stable temperature. This module typically includes a power resistor responsible for heating, a thermistor for temperature measurement, and a module for controlling the heating current. Temperature control is achieved by adjusting the heating current and combining it with the measured temperature data.

[0007] On the one hand, the temperature control module itself has a specific structure, which occupies a large space in the nuclear magnetic resonance quantum computing system. On the other hand, when using this nuclear magnetic resonance quantum computing system for quantum computing, the temperature control module usually needs a long time to stabilize the temperature, which is very inconvenient and inefficient. Utility Model Content

[0008] 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.

[0009] In a first aspect, embodiments of the present invention provide a quantum computing system, comprising: a magnet, a sample module, a main control board, a probe, a control coil, a field-locking coil, a shimming current source, and at least one set of shimming coils electrically connected to the shimming current source; wherein:

[0010] The magnet comprises two permanent magnets; the two permanent magnets are symmetrically arranged on both sides of the sample module;

[0011] The shimming coil is positioned between the permanent magnet and the sample module; the shimming current source is connected to the main control board to supply power to the shimming coil; the main control board controls the current magnitude of the shimming coil through the shimming current source.

[0012] The sample module contains a sample that serves as a carrier of qubits and a sample for locking the field.

[0013] The probe, control coil, and field-locking coil are electrically connected to the main control board. The probe and control coil are sleeved outside the sample of the quantum bit carrier, and the field-locking coil is sleeved outside the sample used for field locking.

[0014] The control coil is used to emit radio frequency pulses of at least one frequency corresponding to the control signal sent by the main control board, so as to manipulate the atomic nuclei that serve as the carriers of the quantum bits.

[0015] The probe is used to sense the first nuclear magnetic signal when the atomic nucleus, which is a quantum bit, undergoes nuclear magnetic resonance;

[0016] The field-locking coil is used to emit a radio frequency pulse corresponding to the field-locking signal according to the field-locking signal sent by the main control board, so as to excite the field-locking atomic nuclei; and to sense a second nuclear magnetic signal when the field-locking atomic nuclei undergo nuclear magnetic resonance;

[0017] The main control board is used to generate and send the field-locking signal when not performing quantum computing, and to receive and demodulate the second nuclear magnetic resonance signal returned by the field-locking coil, and to calibrate and save the frequency of the control signal used to manipulate the quantum bits; when performing quantum computing, it generates and sends the control signal according to the latest calibrated frequency of the control signal, and receives and demodulates the first nuclear magnetic resonance signal returned by the probe corresponding to the control signal.

[0018] In one embodiment, the main control board 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:

[0019] The programmable logic device is used to modulate and generate the control signal and the field-locking signal, and to demodulate the second NMR signal returned by the field-locking coil and the first NMR signal returned by the probe;

[0020] 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.

[0021] The analog-to-digital conversion module is used to convert the second NMR signal returned by the field-locking coil and the first NMR signal returned by the probe into analog-to-digital signals, convert them into corresponding digital signals, and send them to the programmable logic device.

[0022] In one embodiment, the quantum computing system further includes: at least one first radio frequency switch, at least one channel of control signal processing circuit, and at least one channel of first nuclear magnetic signal processing circuit corresponding to the control signal processing circuit of at least one channel.

[0023] Each control signal processing circuit and its corresponding first nuclear magnetic resonance signal processing circuit are connected to a first radio frequency switch and switch operation via the first radio frequency switch;

[0024] At least one channel of control signal processing circuit and the at least one first radio frequency switch are connected between the digital-to-analog converter module of the main control board and the control coil;

[0025] At least one channel of first nuclear magnetic resonance signal processing circuit and at least one first radio frequency switch are connected between the analog-to-digital conversion module of the main control board and the probe;

[0026] The first radio frequency switch conducts the control coil, control signal processing circuit, and main control board when the control signal is transmitted; and conducts the probe, first nuclear magnetic resonance signal processing circuit, and main control board when the control signal is turned off and a non-lock field signal is transmitted.

[0027] In one embodiment, the control signal processing circuit includes: a power amplifier circuit; the power amplifier circuit is used to amplify the control signal emitted by the main control board;

[0028] The first nuclear magnetic resonance signal processing circuit includes: a first filtering circuit and a first low-noise amplifier circuit;

[0029] The first filtering circuit is used to filter the first nuclear magnetic resonance signal sensed by the probe;

[0030] The first low-noise amplifier circuit is used to amplify the filtered first nuclear magnetic resonance signal.

[0031] In one embodiment, the first filtering circuit is a band-pass filter circuit or a low-pass filter circuit.

[0032] In one embodiment, the first filtering circuit and the first radio frequency switch are integrated into the same module.

[0033] In one embodiment, when the control signal processing circuit of the at least one channel is a multi-channel circuit, the control signal processing circuits of different channels are used to process control signals of different frequencies for manipulating different atomic nuclei.

[0034] In one embodiment, when control signals of different frequencies are sent sequentially, control signals of different frequencies are processed by a control signal processing circuit of the same channel, and first nuclear magnetic resonance (NMR) signals of different frequencies are processed by a first NMR signal processing circuit of the same channel.

[0035] In one embodiment, the quantum computing system further includes: a lock field signal transmission path, a second nuclear magnetic signal processing circuit, and a second radio frequency switch;

[0036] The field-locking signal transmission path and the second nuclear magnetic signal processing circuit are respectively connected to the second radio frequency switch, and are switched to work by the second radio frequency switch;

[0037] The field-locking signal transmission path and the second radio frequency switch are connected between the digital-to-analog converter module of the main control board and the field-locking coil;

[0038] The second nuclear magnetic resonance signal processing circuit and the second radio frequency switch are connected between the analog-to-digital conversion module of the main control board and the field-locking coil.

[0039] In one embodiment, the second nuclear magnetic resonance signal processing circuit includes: a second filtering circuit and a second low-noise amplifier circuit;

[0040] The second filtering circuit is used to filter the second nuclear magnetic signal induced by the field-locking coil;

[0041] The second low-noise amplifier circuit is used to amplify the filtered second nuclear magnetic resonance signal.

[0042] In one embodiment, the second filtering circuit is a band-pass filter circuit or a low-pass filter circuit.

[0043] In one embodiment, the second filter circuit and the second RF switch are integrated into the same module.

[0044] In one embodiment, the field lock signal transmission path and one of the channels in the control signal processing circuit of multiple channels are configured as the same circuit;

[0045] The second nuclear magnetic resonance signal processing circuit and one channel of the first nuclear magnetic resonance signal processing circuit with multiple channels are configured as the same circuit.

[0046] In one embodiment, the field-locking signal transmission path and the control signal processing circuit for all channels are configured as the same circuit;

[0047] The second NMR signal processing circuit and the first NMR signal processing circuit for all channels are configured as the same circuit.

[0048] In one embodiment, the quantum computing system further includes: a first resonant circuit and a second resonant circuit;

[0049] A first resonant circuit is connected between the first radio frequency switch and the control coil, and between the first radio frequency switch and the probe;

[0050] The second resonant circuit is connected between the second RF switch and the field-locking coil.

[0051] In one embodiment, the probe, the control coil, and the field-locking coil share the same coil.

[0052] In one embodiment, the sample module contains a mixed sample of a sample serving as a qubit carrier and a sample used for field locking, and the mixed sample is disposed in the middle of a shared coil.

[0053] In one embodiment, the mixed sample is a mixed solution of dimethyl phosphite and hexafluorobenzene, wherein dimethyl phosphite is the sample used as a qubit carrier; and hexafluorobenzene is the sample used for field locking; or

[0054] The mixed sample is a mixture of aqueous phosphorous acid and hexafluorobenzene, wherein the aqueous phosphorous acid is the sample used as the quantum bit carrier; and the hexafluorobenzene is the sample used for field locking; or

[0055] The 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.

[0056] In one embodiment, the control coil and the probe share the same coil, the field-locking coil uses a different coil, and the coil shared by the control coil and the probe is arranged adjacent to the field-locking coil.

[0057] In one embodiment, the sample for the quantum bit carrier and the sample for locking the field are placed separately in the sample module;

[0058] The sample used as a quantum bit carrier is placed in the middle of the coil shared by the control coil and the probe; the sample used for field locking is placed in the middle of the field locking coil.

[0059] In one embodiment, the sample serving as the quantum bit carrier is dimethyl phosphite or an aqueous solution of phosphorous acid; the sample used for field locking is hexafluorobenzene; or

[0060] The sample used as the quantum bit carrier is trifluoroiodide; the sample used for field locking is acetone.

[0061] In one embodiment, the permanent magnet is further provided with a magnetically conductive yoke.

[0062] Secondly, this utility model embodiment provides a nuclear magnetic resonance quantum computer, including: a quantum computing software module and a quantum computing system as described above;

[0063] The quantum computing software module is communicatively connected to the main control board of the quantum computing system.

[0064] The beneficial effects of the above-mentioned technical solutions provided by the embodiments of this utility model include at least the following:

[0065] The quantum computing system and nuclear magnetic resonance quantum computer provided in this embodiment of the invention eliminate the need for existing temperature control modules. Instead, they achieve automatic calibration of the control signal frequency by emitting a lock-in signal through a lock-in coil and inducing a second nuclear magnetic resonance signal. Even when the ambient temperature changes, the quantum computing system can achieve rapid and accurate calibration of the control signal frequency, improving the efficiency of quantum computing. This avoids the problems of long temperature control time, low efficiency, and large physical space requirements associated with using a temperature control module to control the magnet's temperature in existing technologies. The result is a more compact, highly integrated, and space-saving quantum computing system. Furthermore, in this embodiment, shimming coils are positioned on both sides of the sample module to generate a compensating magnetic field for the permanent magnet's magnetic field, achieving a more uniform magnetic field, reducing external magnetic interference, and ensuring the precision of quantum bit manipulation during measurement and control, as well as the accuracy of the quantum computing results.

[0066] In one embodiment, the probe, control coil, and field-locking coil are implemented using a single coil, enabling the transmission and reception of multiple signals. This approach offers advantages such as a simple and compact structure and higher integration.

[0067] In one embodiment, processing control signals of different frequencies through a control signal processing circuit in the same channel, and processing first nuclear magnetic resonance signals of different frequencies through a first nuclear magnetic resonance signal processing circuit in the same channel, further improves the integration of the quantum computing system and is beneficial to the miniaturization of the quantum computing system.

[0068] In one embodiment, the control signal processing circuits for the field-locking signal transmission path and all channels are configured as the same circuit; the second nuclear magnetic resonance signal processing circuit and the first nuclear magnetic resonance signal processing circuits for all channels are configured as the same circuit, which further improves the integration of the quantum computing system, reduces the hardware complexity, makes the structure of the quantum computing system simpler, occupies less physical space, and is conducive to the miniaturization of the quantum computing system.

[0069] 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.

[0070] 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

[0071] 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:

[0072] Figure 1 This is a schematic diagram of the quantum computing system in an embodiment of the present invention;

[0073] Figure 2 This is a schematic diagram of the molecular structure of dimethyl phosphite (C2H7O3P) in the embodiments of this utility model;

[0074] Figure 3 This is a schematic diagram of the relevant circuitry of the quantum computing system in Embodiment 1 of this utility model;

[0075] Figure 4 This is a schematic diagram of the relevant circuitry of the quantum computing system in Embodiment 2 of this utility model;

[0076] Figure 5 This is a schematic diagram of the relevant circuitry of the quantum computing system in Embodiment 3 of this utility model;

[0077] Figure 6 This is a schematic diagram of the structure of the nuclear magnetic resonance quantum computer according to an embodiment of the present invention.

[0078] Explanation of reference numerals in the attached figures:

[0079] 100. Quantum computing systems;

[0080] 200. Quantum computing software module;

[0081] 1. Magnet; 2. Sample module; 3. Main control board; 4. Probe; 5. Control coil; 6. Field-locking coil; 7. Field-shielding coil; 8. Field-shielding current source; 9. Programmable logic device; 10. Digital-to-analog converter module; 11. Analog-to-digital converter module; 12. Control signal processing circuit; 13. First nuclear magnetic resonance signal processing circuit; 14. First radio frequency switch; 15. Power amplifier circuit; 16. First filter circuit; 17. First low-noise amplifier circuit; 18. Field-locking signal transmission path; 19. Second nuclear magnetic resonance signal processing circuit; 20. Second radio frequency switch; 21. Second filter circuit; 22. Second low-noise amplifier circuit; 23. First resonant circuit; 24. Second resonant circuit; 25. Permanent magnet. Detailed Implementation

[0082] 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.

[0083] The quantum computing system provided in this embodiment of the present invention refers to... Figure 1 As shown, it includes: a magnet 1, a sample module 2, a main control board 3, a probe 4, a control coil 5, a field-locking coil 6, a shimming current source 8, and at least one set of shimming coils 7 electrically connected to the shimming current source 8; wherein:

[0084] Magnet 1 includes two permanent magnets 25; the two permanent magnets 25 are symmetrically arranged on both sides of sample module 2;

[0085] A shimming coil is positioned between the permanent magnet 25 and the sample module 2; a shimming current source 8 supplies power to the shimming coil 7; the shimming coil 7 is positioned between the permanent magnet 25 and the sample module 2; the shimming current source 8 is connected to the main control board 3 to supply power to the shimming coil 7; the main control board 3 controls the current magnitude of the shimming coil 7 through the shimming current source 8.

[0086] Sample module 2 contains a sample that serves as a carrier of qubits and a sample used for field locking;

[0087] Probe 4, control coil 5 and field-locking coil 6 are electrically connected to the main control board 3 respectively. Probe 4 and control coil 5 are sleeved outside the sample of the quantum bit carrier, and field-locking coil 6 is sleeved outside the sample used for field locking.

[0088] The control coil 5 is used to transmit radio frequency pulses of at least one frequency corresponding to the control signal sent by the main control board 3, so as to manipulate the atomic nuclei that serve as the carrier of the quantum bits.

[0089] Probe 4 is used to sense the first nuclear magnetic signal when the atomic nucleus, which is a quantum bit, undergoes nuclear magnetic resonance;

[0090] The field-locking coil 6 is used to transmit a radio frequency pulse corresponding to the field-locking signal sent by the main control board 3 to excite the field-locking atomic nuclei; and to sense a second nuclear magnetic signal when the field-locking atomic nuclei undergo nuclear magnetic resonance.

[0091] The main control board 3 is used to generate and send a field-locking signal when not performing quantum computing, and to receive and demodulate the second nuclear magnetic resonance signal returned by the field-locking coil 6, and to calibrate and save the frequency of the control signal used to manipulate the quantum bits; when performing quantum computing, it generates and sends the control signal according to the frequency of the latest calibrated control signal, and receives and demodulates the first nuclear magnetic resonance signal returned by the probe 4 corresponding to the control signal.

[0092] In one embodiment, a magnetically conductive yoke may also be provided on the two permanent magnets of the magnet 1; the magnetically conductive yoke has the functions of enhancing the magnetic field strength and reducing magnetic leakage. In this embodiment of the present invention, a highly uniform magnetic field can be generated by finely adjusting the structure of the permanent magnet, 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).

[0093] Due to factors such as processing precision, the magnetic field uniformity of the permanent magnet 25 produced by the permanent magnet material cannot meet the requirements of quantum computing (even if these permanent magnets are subjected to very careful passive shimming). Therefore, it is necessary to use shimming coils of different shapes to generate a compensating magnetic field in order to achieve superposition with the magnetic field of the permanent magnet 25 and finally obtain a magnetic field with higher uniformity.

[0094] Reference Figure 1 As shown, there are multiple sets of shimming coils 7, each set of shimming coils 7 is symmetrically arranged between the permanent magnet 25 and the sample module 2. For example, there are 12 sets of shimming coils 7, and the magnitude of the current in the shimming coils 7 can be controlled by the main control board 3.

[0095] In specific implementations, the probe 4, control coil 5, and field-locking coil 6 can be implemented using the same coil or as multiple different coils. This embodiment of the invention does not limit this.

[0096] For example, probe 4, control coil 5, and field-locking coil 6 can share the same coil. Figure 1 (This is the illustrated case). In this case, the sample module contains a mixed sample of a sample that serves as a carrier of qubits 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.

[0097] 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 a sample used as a quantum bit carrier; and hexafluorobenzene is a sample used for field locking.

[0098] Optionally, in the mixed sample, the volume ratio of the above-mentioned dimethyl phosphite and hexafluorobenzene is 7:3.

[0099] 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.

[0100] Optionally, in the mixed sample, the volume ratio of trifluoroiodide (C2F3I) to acetone (C3H6O) is 7:3.

[0101] Understandably, different samples can be selected for different numbers of qubits, and this application does not impose any restrictions on this.

[0102] For example, probe 4 and control coil 5 share the same coil, while the field-locking coil uses a different coil. Figure 1 (This situation is not illustrated.) The coil shared by the control coil and the probe is arranged adjacent to the field-locking coil. Correspondingly, the sample for the qubit carrier and the sample for field-locking are placed separately in the sample module; the sample used as the qubit carrier is placed in the middle of the coil shared by the control coil and the probe, and the sample used for field-locking is placed in the middle of the field-locking coil.

[0103] 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.

[0104] For example, the sample used as the carrier of qubits is trifluoroiodide; the sample used for field locking is acetone.

[0105] 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.

[0106] Regardless of whether probe 4, control coil 5, and field-locking coil 6 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 temporal sequence relationship.

[0107] For the field-locking coil 6, it operates during the periods when neither the control coil 5 nor the probe 4 is working. In other words, the field-locking coil 6 does not work when transmitting control signals and when using the probe 4 to detect the first NMR signal. The field-locking coil 6 only works when the system does not need to use the control coil 5 to transmit the radio frequency pulse corresponding to the control signal or use the probe 4 to detect the first NMR signal.

[0108] For control coil 5, 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 mixed sample.

[0109] For probe 4, the first nuclear magnetic resonance signal (also a radio frequency signal) of the quantum bit is sensed only after the control coil 5 has finished transmitting the control signal.

[0110] In one embodiment, when the probe 4, control coil 5, and field-locking coil 6 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.

[0111] In one embodiment, the aforementioned main control board 3, refer to Figure 1 As shown, it specifically includes: a programmable logic device 9, a digital-to-analog converter module 10, and an analog-to-digital converter module 11, with the programmable logic device 9 connected to both the digital-to-analog converter module 10 and the analog-to-digital converter module 11; wherein:

[0112] Programmable logic device 9 is used to modulate and generate the control signal and the field-locking signal, and to demodulate the second NMR signal returned by the field-locking coil 6 and the first NMR signal returned by the probe 4;

[0113] 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.

[0114] The digital-to-analog converter (DAC) 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, so as to send it to the control coil 5 or the field-locking coil 6.

[0115] 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 signal conversion.

[0116] The analog-to-digital converter (ADC) 11 is used to convert the second NMR signal returned by the field-locking coil 6 and the first NMR signal returned by the probe 4 into analog-to-digital signals, and send them to the programmable logic device 9.

[0117] The second NMR signal returned by the field-locking coil 6 and the first NMR signal returned by the probe 4 are analog signals. The analog-to-digital converter module 11 converts them into corresponding digital signals and returns them to the FPGA module 9.

[0118] 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.

[0119] 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.

[0120] Taking the selection of dimethyl phosphite as the physical bit carrier for quantum computing as an example, Figure 2 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.

[0121] 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).

[0122] For example, the fluorine nuclei in hexafluorobenzene (C6F6) or the hydrogen nuclei in acetone (C3H6O) in the field-locking sample are excited by the radio frequency signal emitted by the field-locking coil 6, and a second nuclear magnetic signal is induced by the field-locking coil 6 and transmitted to the main control board 3 for demodulation.

[0123] 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.

[0124] In the sample module, 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.

[0125] However, in quantum computing systems, the magnetic field strength of magnet 1 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 carriers of qubits and the atomic nuclei used as lock fields (although the ratio between the two does not change).

[0126] Based on the above principles, the field-locking signal and the second nuclear magnetic resonance signal can be used to calibrate the frequency of the control signal to be transmitted in the future.

[0127] When not performing quantum computing, the lock field signal is sent periodically. The programmable logic device 9 in the main control board 3 demodulates the second nuclear magnetic signal that is sensed back, calculates how much the current frequency deviates from the previously calculated frequency, and then automatically adjusts to the latest frequency of the lock field signal when the lock field signal is transmitted next time (i.e., performs frequency compensation). Since there is a fixed ratio relationship between the frequency and the frequency of the atomic nucleus used as the carrier of the quantum bits, if the next time a control signal is to be transmitted instead of the lock field signal, the frequency corresponding to the control signal can be obtained based on the latest frequency of the lock field signal, thereby realizing the automatic calibration of the frequency of the control signal.

[0128] 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 control signal can be calculated based on this latest frequency value.

[0129] This utility model embodiment abandons the existing temperature control module and achieves automatic calibration of the control signal frequency by transmitting a lock field signal and inducing a second nuclear magnetic signal. Even when the ambient temperature changes, it can achieve fast and accurate calibration of the control signal frequency. This avoids the problems of long temperature control time, low efficiency, and physical space occupation caused by using a temperature control module to control the temperature of the magnet in the prior art. While improving the quantum computing efficiency of the quantum computing system, it also makes the quantum computing system more compact, more integrated, and occupies less space.

[0130] In one embodiment, the above-described quantum computing system, referring to Figure 1 As shown, it also includes: at least one first radio frequency switch 14, at least one channel control signal processing circuit 12, and at least one channel first nuclear magnetic resonance signal processing circuit 13 corresponding to the at least one channel control signal processing circuit 12; wherein:

[0131] Each control signal processing circuit 12 and its corresponding first nuclear magnetic resonance signal processing circuit 13 are respectively connected to a first radio frequency switch 14 and switch operation through the first radio frequency switch 14;

[0132] At least one channel of control signal processing circuit 12 and at least one first radio frequency switch 14 are connected between the digital-to-analog converter module 10 and the control coil 5 of the main control board 3;

[0133] At least one channel of the first nuclear magnetic resonance signal processing circuit 13 and at least one first radio frequency switch 14 are connected between the analog-to-digital conversion module 11 of the main control board 3 and the probe 4;

[0134] The first radio frequency switch 14 conducts the control coil 5, the control signal processing circuit 12, and the main control board 3 when the control signal is transmitted; when the control signal is turned off and the non-lock signal is transmitted, it conducts the probe 4, the first nuclear magnetic resonance signal processing circuit 13, and the main control board 3.

[0135] The first radio frequency switch 14 is responsible for switching between the control signal processing circuit 12 and the first nuclear magnetic resonance signal processing circuit 13.

[0136] The reason why the control signal processing circuit 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 circuit 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 circuits 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).

[0137] In one embodiment, when control signals of different frequencies are sent sequentially, the multiple control signal processing circuits 12 of different channels can be implemented using a single circuit. Correspondingly, the multiple first NMR signal processing circuits 13 of different channels can also be implemented using a single circuit. That is, control signals of different frequencies are processed through the same channel control signal processing circuit 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 NMR signal processing circuit 13.

[0138] Furthermore, the aforementioned control signal processing circuit 12 specifically includes: a power amplifier circuit 15; the power amplifier circuit 15 is used to amplify the control signals emitted by the main control board 3;

[0139] 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 can have a gain of 56dB and a maximum power of 50W in the range of 10-60MHz.

[0140] In one embodiment, a filter circuit may also be provided on the control signal processing circuit 12. Figure 1 (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.

[0141] Correspondingly, the first nuclear magnetic resonance signal processing circuit 13 specifically includes: a first filter circuit 16 and a first low-noise amplifier circuit 17;

[0142] The first filter circuit 16 is used to filter the first nuclear magnetic resonance signal sensed by the probe 4;

[0143] The first low-noise amplifier circuit 17 is used to amplify the filtered first nuclear magnetic resonance signal.

[0144] For the loop of the first NMR signal, the first NMR signal returned from the probe 4 is first filtered by the first filter circuit 16, and then amplified by the first low-noise amplifier circuit 17. In an optional embodiment, if the first low-noise amplifier circuit 17 is a multi-stage amplifier circuit, the first filter circuit 16 can also be set between the multi-stage amplifier circuits, for example, between two stages of amplifier circuits.

[0145] After being amplified by the first low-noise amplifier circuit 17, the first nuclear magnetic resonance signal can be amplified to the range of 1mV to 1V.

[0146] Optionally, the first filter circuit 16 described above can be a band-pass filter circuit or a low-pass filter circuit.

[0147] In one embodiment, the first filter circuit 16 and the first radio frequency switch 14 are integrated into the same module.

[0148] In one embodiment, the above-described quantum computing system, referring to Figure 1 As shown, it may also include: a field-locking signal transmission path 18, a second nuclear magnetic signal processing circuit 19, and a second radio frequency switch 20;

[0149] The field-locking signal transmission path 18 and the second nuclear magnetic signal processing circuit 19 are respectively connected to the second radio frequency switch 20, and are switched to work by the second radio frequency switch 20;

[0150] The field-locking signal transmission path 18 and the second radio frequency switch 20 are connected between the digital-to-analog converter module 10 of the main control board 3 and the field-locking coil 6;

[0151] Correspondingly, the second nuclear magnetic signal processing circuit 19 and the second radio frequency switch 20 are connected between the analog-to-digital conversion module 11 and the field-locking coil 6 of the main control board 3.

[0152] 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 transmission path 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.

[0153] Of course, in an optional embodiment, the above-mentioned field-locking signal transmission path 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 circuit 12, and will not be described again here.

[0154] The second RF switch 20 is responsible for switching between the field lock signal transmission path 18 and the second nuclear magnetic resonance signal processing circuit 19. First, the field lock signal is transmitted. After the transmission is completed, it switches to the second nuclear magnetic resonance signal processing circuit 19, so that the second nuclear magnetic resonance signal induced by the field lock coil 6 can be successfully processed by the second nuclear magnetic resonance signal processing circuit 19 and returned to the main control board 3.

[0155] In one embodiment, the second nuclear magnetic resonance signal processing circuit 19 specifically includes: a second filter circuit 21 and a second low-noise amplifier circuit 22;

[0156] The second filter circuit 21 is used to filter the second nuclear magnetic signal induced by the field-locking coil 6;

[0157] The second low-noise amplifier circuit 22 is used to amplify the filtered second nuclear magnetic resonance signal.

[0158] The second filter circuit 21 functions similarly to the first filter circuit 16 described above, and the second low-noise amplifier circuit 22 functions similarly to the first low-noise amplifier circuit 17 described above, so they will not be described again here.

[0159] In one embodiment, the second filter circuit 21 and the second radio frequency switch 20 are integrated into the same module.

[0160] In one embodiment, the field-locking signal transmission path 18 and one of the multiple channels of the control signal processing circuit 12 can be configured as the same circuit;

[0161] Accordingly, the second nuclear magnetic resonance signal processing circuit 19 and one of the multiple channels of the first nuclear magnetic resonance signal processing circuit 13 can also be configured as the same circuit.

[0162] In one embodiment, the above-described quantum computing system, referring to Figure 1 As shown, it also includes: a first resonant circuit 23 and a second resonant circuit 24; wherein:

[0163] The first resonant circuit 23 is connected between the first RF switch 14 and the control coil 5, and between the first RF switch 14 and the probe 4;

[0164] The second resonant circuit 24 is connected between the second RF switch 20 and the field-locking coil 6.

[0165] The first resonant circuit 23 tunes different control signals to the required frequencies so that the control signals can be transmitted to the control coil 5, facilitating the control coil 5 to emit radio frequency signals of a preset frequency for detection. It also returns the corresponding frequency of the first nuclear magnetic resonance (NMR) signal completely and efficiently to the programmable logic device 9. Without the first resonant circuit 23, when the control signal enters the control coil 5, it may not resonate due to impedance mismatch or other reasons, and most of the signal will be reflected back. Thus, the control signal cannot enter the control coil completely and efficiently, and consequently, the radio frequency pulse cannot be completely and efficiently delivered to the corresponding sample. Even if it is delivered, the first NMR signal sensed by the probe 4 may not be completely returned.

[0166] Since the transmitted control signal and the received first nuclear magnetic resonance signal are at the same frequency, their resonant points are the same, and the same resonant circuit is needed for reception as for the transmitted control signal.

[0167] For first nuclear magnetic resonance signals of different frequencies, the same first resonant circuit 23 can receive first nuclear magnetic resonance signals of different frequencies through different inductors, so that the probe 4 can transmit first nuclear magnetic resonance signals of different frequencies back to the programmable logic device 9 through a resonant circuit.

[0168] The function of the second resonant circuit 24 is similar to that of the first resonant circuit 23, but it is designed for a single-frequency field-locking signal and a second nuclear magnetic resonance signal. The specific functions and principles will not be elaborated here.

[0169] 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.

[0170] Example 1:

[0171] The structure of Embodiment 1 of this utility model can be referred to Figure 3 As shown, the quantum computing system includes: a magnet ( Figure 3 (not shown in the image), sample module ( Figure 3 (not shown in the image), uniform current source and uniform coil (in...) Figure 3 (Not shown in the diagram) Main control board, probe, control coil and field-locking coil, control signal processing circuit, first NMR signal processing circuit, first RF switch, field-locking signal transmission path, second NMR signal processing circuit, second RF switch, first resonant circuit and second resonant circuit, etc. The probe, control coil and field-locking coil are the same coil. The structure and function of the magnet, 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 3 Each module shown in the diagram will be explained.

[0172] 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.

[0173] 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.

[0174] 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.

[0175] exist Figure 3 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.

[0176] The main control board contains an FPGA module and ADCs and DACs connected to the FPGA module.

[0177] The DAC has two outputs, corresponding to the control signal processing circuit (including the power amplifier circuit) and the field lock signal transmission path, respectively.

[0178] The control signal processing circuit includes a power amplifier circuit;

[0179] The field-lock signal transmission path is connected between the DAC and the second RF switch.

[0180] The ADC has two inputs: one from the second NMR signal processing circuit (including low-noise amplification and bandpass filtering circuits), and the other from either of the two first NMR signal processing circuits (each channel includes low-noise amplification and bandpass filtering circuits). These two first NMR signal processing circuits 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 board at any given time. Therefore, the two first NMR signal processing circuits can share the same input channel of the ADC. Figure 3 In the diagram, the first nuclear magnetic resonance signal processing circuit for the two channels is labeled as: First Nuclear Magnetic Resonance Signal Processing Circuit (H&P).

[0181] In Example 1, the control signals corresponding to the hydrogen nuclei and the phosphorus nuclei share the same control signal processing circuit. Figure 3 The label indicates: Control Signal Processing Circuit (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.

[0182] In Example 1, the control signals and the first NMR signal for hydrogen and phosphorus nuclei are processed by the same resonant circuit (first resonant circuit), while the field-locking signal and the second NMR signal for fluorine nuclei are processed by a different resonant circuit (second resonant circuit). Both of these resonant circuits can be, for example, LC resonant circuits.

[0183] Example 2:

[0184] The structure of Embodiment 2 of this utility model can be referred to Figure 4 As shown, the quantum computing system includes: a magnet ( Figure 4 (not shown in the image), sample module ( Figure 4 (not shown in the image), uniform current source and uniform coil (in...) Figure 4 (Not shown in the diagram) The main control board, probe, control coil and field-locking coil, control signal processing circuit, first NMR signal processing circuit, first RF switch, field-locking signal transmission path, second NMR signal processing circuit, second RF switch, first resonant circuit and second resonant circuit, etc. The probe, control coil and field-locking coil are the same coil. The structure and function of the magnet, 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 4 Each module shown in the diagram will be explained.

[0185] 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 4 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.

[0186] Unlike Example 1, in Example 2, the field-locking signal transmission path corresponding to the fluorine nucleus and the control signal processing circuit corresponding to the hydrogen nucleus share the same circuit. Figure 4 The markings indicate the control signal processing circuit and the field-locking signal transmission path; the second NMR signal processing circuit corresponding to the fluorine nucleus shares the same circuit implementation as the first NMR signal processing circuit corresponding to the hydrogen nucleus. Figure 4 The circuit is labeled as: First NMR signal processing circuit (H) & Second NMR signal processing circuit (F), see reference. Figure 4 As shown, the circuit includes a low-noise amplifier and bandpass filter circuit.

[0187] The control signal processing circuit for phosphorus nuclei and the first nuclear magnetic resonance signal processing circuit are set separately from the signal processing circuits for fluorine nuclei and hydrogen nuclei.

[0188] When the control signal processing circuit corresponding to the hydrogen nucleus and the field-locking signal transmission path corresponding to the fluorine nucleus share the same circuit, refer to... Figure 4 As shown, the circuit includes a power amplifier circuit.

[0189] The specific structures of the first nuclear magnetic resonance signal processing circuit and the second nuclear magnetic resonance signal processing circuit are similar to those in the aforementioned embodiment 1, and will not be described again here.

[0190] Since the field lock signal corresponding to the fluorine nucleus and the control signal corresponding to the hydrogen nucleus also have different timing sequences and are not generated and transmitted simultaneously, the control signal processing circuit corresponding to the hydrogen nucleus and the field lock signal transmission path corresponding to the fluorine nucleus can share the same circuit.

[0191] 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.

[0192] 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.

[0193] In Example 2, the first resonant circuit and the second resonant circuit were also used to process the radio frequency signals of phosphorus nuclei and the radio frequency signals of hydrogen and fluorine nuclei, respectively.

[0194] Example 3:

[0195] The structure of Embodiment 3 of this utility model can be referred to Figure 5 As shown, the quantum computing system includes: a magnet ( Figure 5 (not shown in the image), sample module ( Figure 5 (not shown in the image), uniform current source and uniform coil (in...) Figure 5 (Not shown in the diagram) The main control board, probe, control coil and field-locking coil, control signal processing circuit, first nuclear magnetic resonance signal processing circuit, first radio frequency switch, field-locking signal transmission path, second nuclear magnetic resonance signal processing circuit, second radio frequency switch (which is the same device as the first radio frequency switch and therefore not shown separately), first resonant circuit and second resonant circuit (which is the same circuit as the first resonant circuit and therefore not shown separately), etc. Among them, the probe, control coil and field-locking coil are the same coil. The structure and function of the magnet, sample module, shimming current source and shimming coil are the same as those in the previous embodiment and will not be repeated here.

[0196] Unlike Embodiments 1 and 2, the control signal processing circuits and field lock signal transmission paths for all channels are implemented using the same circuit. Figure 5The diagram only illustrates the structure of the control signal processing circuit for one channel, labeled: Control Signal Processing Circuit (F) & Field Lock Signal Transmission Path (H). This circuit includes a power amplifier. Furthermore, since the first and second NMR signal processing circuits for multiple channels are implemented using the same circuit, Figure 5 The diagram only shows the structure of the first nuclear magnetic resonance signal processing circuit for one channel, labeled as: First nuclear magnetic resonance signal processing circuit (F) & Second nuclear magnetic resonance signal processing circuit (H), which includes low-noise amplification and bandpass filtering circuits.

[0197] Furthermore, the functions of the first and second RF switches are implemented using the same RF switch. Figure 5 Only the first radio frequency switch is shown in the diagram.

[0198] In Embodiment 3, the functions of the first resonant circuit and the second resonant circuit are also implemented using the same circuit; therefore... Figure 5 Only the first resonant circuit is shown in the diagram. One end of the first resonant circuit is grounded.

[0199] Unlike Examples 1 and 2, the sample module in Example 3 contained a mixed sample solution of trifluoroiodide (C2F3I) and acetone (C3H6O). In the magnetic field, the three fluorine nuclei on the 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 5 In this context, the letter H represents the hydrogen nucleus, and the letter F represents the fluorine nucleus.

[0200] Whether it is the control signal of the three fluorine atoms of the three qubits or the field-locking signal corresponding to 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.

[0201] In Example 3, from Figure 5 As can be seen, the ADC has only one input and the DAC has only one output.

[0202] 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.

[0203] Based on the same inventive concept, this utility model also provides a desktop nuclear magnetic resonance quantum computer, referring to... Figure 6 As shown, it includes: a quantum computing software module 200 and a quantum computing system 100 as provided in the foregoing embodiments;

[0204] The quantum computing software module 200 is connected to the main control board of the quantum computing system 100.

[0205] 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: The system comprises a magnet, a sample module, a main control board, a probe, a control coil, a field-locking coil, a field-shielding current source, and at least one set of field-shielding coils electrically connected to the field-shielding current source; wherein: The magnet comprises two permanent magnets; the two permanent magnets are symmetrically arranged on both sides of the sample module; The shimming coil is positioned between the permanent magnet and the sample module; the shimming current source is connected to the main control board to supply power to the shimming coil; the main control board controls the current magnitude of the shimming coil through the shimming current source. The sample module contains a sample that serves as a carrier of qubits and a sample for locking the field. The probe, control coil, and field-locking coil are electrically connected to the main control board. The probe and control coil are sleeved outside the sample of the quantum bit carrier, and the field-locking coil is sleeved outside the sample used for field locking. The control coil is used to emit radio frequency pulses of at least one frequency corresponding to the control signal sent by the main control board, so as to manipulate the atomic nuclei that serve as the carriers of the quantum bits. The probe is used to sense the first nuclear magnetic signal when the atomic nucleus, which is a quantum bit, undergoes nuclear magnetic resonance; The field-locking coil is used to emit a radio frequency pulse corresponding to the field-locking signal according to the field-locking signal sent by the main control board, so as to excite the field-locking atomic nuclei; and to sense a second nuclear magnetic signal when the field-locking atomic nuclei undergo nuclear magnetic resonance; The main control board is used to generate and send the field-locking signal when not performing quantum computing, and to receive and demodulate the second nuclear magnetic resonance signal returned by the field-locking coil, and to calibrate and save the frequency of the control signal used to manipulate the quantum bits; when performing quantum computing, it generates and sends the control signal according to the latest calibrated frequency of the control signal, and receives and demodulates the first nuclear magnetic resonance signal returned by the probe corresponding to the control signal.

2. The quantum computing system as described in claim 1, characterized in that, The main control board 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 both the digital-to-analog converter module and the analog-to-digital converter module; wherein: The programmable logic device is used to modulate and generate the control signal and the field-locking signal, and to demodulate the second NMR signal returned by the field-locking coil and the first NMR signal returned by the probe; 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 NMR signal returned by the field-locking coil and the first NMR signal returned by the probe into analog-to-digital signals, convert them into corresponding digital signals, and send them to the programmable logic device.

3. The quantum computing system as described in claim 2, characterized in that, Also includes: At least one first radio frequency switch, at least one channel of control signal processing circuit, and at least one channel of first nuclear magnetic signal processing circuit corresponding to the control signal processing circuit of at least one channel; Each control signal processing circuit and its corresponding first nuclear magnetic resonance signal processing circuit are connected to a first radio frequency switch and switch operation via the first radio frequency switch; At least one channel of control signal processing circuit and the at least one first radio frequency switch are connected between the digital-to-analog converter module of the main control board and the control coil; At least one channel of first nuclear magnetic resonance signal processing circuit and at least one first radio frequency switch are connected between the analog-to-digital conversion module of the main control board and the probe; The first radio frequency switch conducts the control coil, control signal processing circuit, and main control board when the control signal is transmitted; and conducts the probe, first nuclear magnetic resonance signal processing circuit, and main control board when the control signal is turned off and a non-lock field signal is transmitted.

4. The quantum computing system as described in claim 3, characterized in that, The control signal processing circuit includes: a power amplifier circuit; the power amplifier circuit is used to amplify the control signals emitted by the main control board; The first nuclear magnetic resonance signal processing circuit includes: a first filtering circuit and a first low-noise amplifier circuit; The first filtering circuit is used to filter the first nuclear magnetic resonance signal sensed by the probe; The first low-noise amplifier circuit is used to amplify the filtered first nuclear magnetic resonance signal.

5. The quantum computing system as described in claim 4, characterized in that, The first filtering circuit is a band-pass filter circuit or a low-pass filter circuit.

6. The quantum computing system as described in claim 4, characterized in that, The first filter circuit and the first radio frequency switch are integrated into the same module.

7. The quantum computing system as described in claim 3, characterized in that, When the control signal processing circuit of the at least one channel has multiple channels, the control signal processing circuits of different channels are used to process control signals of different frequencies for manipulating different atomic nuclei.

8. The quantum computing system as described in claim 3, characterized in that, When control signals of different frequencies are sent sequentially, control signals of different frequencies are processed by the control signal processing circuit of the same channel, and first nuclear magnetic resonance signals of different frequencies are processed by the first nuclear magnetic resonance signal processing circuit of the same channel.

9. The quantum computing system as described in claim 3, characterized in that, Also includes: Lock field signal transmission path, second nuclear magnetic signal processing circuit, and second radio frequency switch; The field-locking signal transmission path and the second nuclear magnetic signal processing circuit are respectively connected to the second radio frequency switch, and are switched to work by the second radio frequency switch; The field-locking signal transmission path and the second radio frequency switch are connected between the digital-to-analog converter module of the main control board and the field-locking coil; The second nuclear magnetic resonance signal processing circuit and the second radio frequency switch are connected between the analog-to-digital conversion module of the main control board and the field-locking coil.

10. The quantum computing system as described in claim 9, characterized in that, The second nuclear magnetic resonance signal processing circuit includes: a second filter circuit and a second low-noise amplifier circuit; The second filtering 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.

11. The quantum computing system as described in claim 10, characterized in that, The second filtering circuit is a band-pass filter circuit or a low-pass filter circuit.

12. The quantum computing system as described in claim 10, characterized in that, The second filter circuit and the second RF switch are integrated into the same module.

13. The quantum computing system as described in claim 9, characterized in that, The field-locking signal transmission path and one of the multiple channels of the control signal processing circuit are configured to be the same circuit; The second nuclear magnetic resonance signal processing circuit and one channel of the first nuclear magnetic resonance signal processing circuit with multiple channels are configured as the same circuit.

14. The quantum computing system as described in claim 9, characterized in that, The control signal processing circuits for the field-locking signal transmission path and all channels are configured as the same circuit; The second NMR signal processing circuit and the first NMR signal processing circuit for all channels are configured as the same circuit.

15. The quantum computing system as described in claim 9, characterized in that, Also includes: First resonant circuit and second resonant circuit; A first resonant circuit is connected between the first radio frequency switch and the control coil, and between the first radio frequency switch and the probe; The second resonant circuit is connected between the second RF switch and the field-locking coil.

16. The quantum computing system according to any one of claims 1-15, characterized in that, The probe, the control coil, and the field-locking coil share the same coil.

17. The quantum computing system as described in claim 16, characterized in that, The sample module contains a mixed sample, which serves as a quantum bit carrier and a sample used for field locking, and the mixed sample is positioned in the middle of a shared coil.

18. The quantum computing system as described in claim 17, characterized in that, The mixed sample is a mixed solution of dimethyl phosphite and hexafluorobenzene, wherein dimethyl phosphite is the sample used as a qubit carrier; and hexafluorobenzene is the sample used for field locking; or The mixed sample is a mixture of aqueous phosphorous acid and hexafluorobenzene, wherein the aqueous phosphorous acid is the sample used as the quantum bit carrier; and the hexafluorobenzene is the sample used for field locking; or The 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.

19. The quantum computing system according to any one of claims 1-15, characterized in that, The control coil and the probe share the same coil, while the field-locking coil uses a separate coil. The coil shared by the control coil and the probe is arranged adjacent to the field-locking coil.

20. The quantum computing system as described in claim 19, characterized in that, In the sample module, the sample for the quantum bit carrier and the sample for locking the field are placed separately. The sample used as a quantum bit carrier is placed in the middle of the coil shared by the control coil and the probe; the sample used for field locking is placed in the middle of the field locking coil.

21. The quantum computing system as described in claim 20, characterized in that, The sample used as the quantum bit carrier is dimethyl phosphite or an aqueous solution of phosphorous acid; the sample used for field locking is hexafluorobenzene; or The sample used as the quantum bit carrier is trifluoroiodide; the sample used for field locking is acetone.

22. The quantum computing system as described in claim 20, characterized in that, The permanent magnet is also provided with a magnetically conductive yoke.

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

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