Quantum computing system and nuclear magnetic resonance quantum computer

Abstract

The invention discloses a quantum computing system, which is characterized by comprising a magnet, a sample module, a main control board, a probe, a control coil and a lock field coil, 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 a corresponding radio frequency pulse 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, demodulating the second nuclear magnetic signal, calibrating the frequency of a control signal and storing the frequency when quantum calculation is not carried out; and according to the frequency of the calibrated control signal, generating and sending the control signal, and receiving and demodulating a first nuclear magnetic signal returned by the probe. According to the invention, the calculation efficiency of the quantum calculation system is improved, the structure of the quantum calculation system is more compact, the integration degree is higher, and the occupied space is smaller.

Description

Technical Field

[0001] The present invention relates to the field of quantum information technology, and particularly to a quantum computing system and a nuclear magnetic resonance quantum computer. Background Art

[0002] At present, there are many physical experimental platforms on which quantum computing systems for realizing quantum computing rely, such as Nuclear Magnetic Resonance (NMR), superconducting quantum chips, ion traps, optical quanta, and so on. Among them, nuclear magnetic resonance is a quantum computing system that started earliest, has been developed most perfectly, and has implemented the most quantum algorithms. The quantum computing system implemented by nuclear magnetic resonance can implement rich quantum computing algorithms under normal temperature and pressure, has mature radio frequency measurement and control technologies, and has simple experimental conditions.

[0003] The nuclear magnetic resonance quantum computing system uses the nuclear spin in a strong magnetic field as quantum bits for quantum computing, and realizes quantum entanglement between different quantum bits through the J coupling between different atomic nuclei in the same molecule.

[0004] If all atomic nuclei are desired to exhibit the same resonance characteristics, the nuclear magnetic resonance quantum computing experimental platform needs to have an extremely stable and uniform magnetic field.

[0005] In the prior art, when a nuclear magnetic resonance quantum computer uses a magnet (such as a superconducting coil, etc.) as a magnetic field source to perform quantum computing in a nuclear magnetic resonance system, there are relatively high requirements for the stability of the magnetic field. In order to avoid the influence of temperature fluctuations on the magnetic field strength, a very stable temperature control is required, and the temperature drift is controlled within a very small range.

[0006] The general solution is to use a complex temperature control module to control the temperature of the magnet to ensure the stability of the nuclear magnetic resonance signal frequency. For example, the temperature control module keeps the magnet at a very stable temperature. The temperature control module usually includes a power resistor responsible for heating, a thermistor responsible for temperature measurement, and a module for controlling the heating current, etc., and realizes the temperature control function by adjusting the heating current and combining the temperature measurement data.

[0007] On the one hand, the above temperature control module has a specific structure itself, which will occupy a relatively 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 takes a relatively long time to stabilize the temperature, which is very inconvenient and has low efficiency. Summary of the Invention

[0008] In view of the above problems, the present invention is proposed to provide a quantum computing system and a nuclear magnetic resonance quantum computer that overcome the above problems or at least partially solve the above problems.

[0009] In a first aspect, an embodiment of the present invention provides a quantum computing system, including: a magnet, a sample module, a main control board, a probe, a control coil, and a lock-in coil; wherein:

[0010] The sample module contains a sample serving as a quantum bit carrier and a sample for lock-in; the sample serving as the quantum bit carrier and the sample for lock-in are arranged in the magnetic field of the magnet;

[0011] The probe, the control coil, and the lock-in coil are connected to the main control board and are arranged between the main control board and the sample module;

[0012] The control coil is configured to emit radio frequency pulses of at least one frequency corresponding to the control signal according to the control signal sent by the main control board;

[0013] The probe is configured to sense a first nuclear magnetic signal when the atomic nucleus serving as a quantum bit in the sample serving as the quantum bit carrier undergoes nuclear magnetic resonance;

[0014] The lock-in coil is configured to emit radio frequency pulses for calibrating the frequency of the control signal according to the lock-in signal sent by the main control board, and sense a second nuclear magnetic signal when the atomic nucleus for lock-in in the sample for lock-in undergoes nuclear magnetic resonance;

[0015] The main control board is configured to generate and send the lock-in signal when quantum computing is not performed, demodulate the second nuclear magnetic signal corresponding to the lock-in signal returned by the lock-in coil, calibrate the frequency of the control signal for manipulating the quantum bit, and save it; when quantum computing is performed, generate and send the control signal according to the calibrated frequency of the control signal, and receive and demodulate the first nuclear magnetic signal corresponding to the control signal returned by the probe.

[0016] In one embodiment, the main control board includes: a programmable logic device, a digital-to-analog conversion module, and an analog-to-digital conversion module, and the programmable logic device is respectively connected to the digital-to-analog conversion module and the analog-to-digital conversion module; wherein:

[0017] The programmable logic device is configured to modulate and generate the control signal and the lock-in signal, and demodulate the second nuclear magnetic signal returned by the lock-in coil and the first nuclear magnetic signal returned by the probe;

[0018] The digital-to-analog conversion module is configured to convert the control signal or the lock-in signal from a digital signal to an analog signal, and convert it into a corresponding analog signal for further sending to the control coil or the lock-in coil;

[0019] The analog-to-digital conversion module is used to convert the second nuclear magnetic signal returned by the lock-in coil and the first nuclear magnetic signal returned by the probe into analog-digital signals, convert them into corresponding digital signals, and send them to the programmable logic device.

[0020] In one embodiment, the above quantum computing system further includes: at least one first RF switch, a control signal processing circuit for at least one channel, and a first nuclear magnetic signal processing circuit for at least one channel corresponding to the control signal processing circuit for at least one channel respectively;

[0021] Each control signal processing circuit and the corresponding first nuclear magnetic signal processing circuit are respectively connected to a first RF switch, and switch to work through the first RF switch;

[0022] The control signal processing circuit for at least one channel and the at least one first RF switch are connected between the digital-to-analog conversion module of the main control board and the control coil;

[0023] The first nuclear magnetic signal processing circuit for at least one channel and the at least one first RF switch are connected between the analog-to-digital conversion module of the main control board and the probe;

[0024] The first RF switch conducts the control coil, the control signal processing circuit, and the main control board when the control signal is transmitted; when the control signal is turned off and a non-lock-in signal is transmitted, it conducts the probe, the first nuclear magnetic signal processing circuit, and the main control board.

[0025] In one embodiment, the control signal processing circuit includes: a power amplification circuit; the power amplification circuit is used to amplify the control signal sent by the main control board;

[0026] The first nuclear magnetic signal processing circuit includes: a first filter circuit and a first low-noise amplification circuit;

[0027] The first filter circuit is used to filter the first nuclear magnetic signal sensed by the probe;

[0028] The first low-noise amplification circuit is used to amplify the filtered first nuclear magnetic signal.

[0029] In one embodiment, the first filter circuit is a band-pass filter circuit or a low-pass filter circuit.

[0030] In one embodiment, the first filter circuit and the first RF switch are integrated into the same module.

[0031] In one embodiment, when the control signal processing circuit for at least one channel is for multiple channels, the control signal processing circuits for different channels are used to process control signals with different frequencies for manipulating different atomic nuclei.

[0032] In one embodiment, in the case where control signals of different frequencies are sent successively, the control signals of different frequencies are processed by the control signal processing circuit of the same channel, and the first nuclear magnetic signals of different frequencies are processed by the first nuclear magnetic signal processing circuit of the same channel.

[0033] In one embodiment, the quantum computing system further includes: a lock-in signal emission path, a second nuclear magnetic signal processing circuit, and a second radio frequency switch;

[0034] The lock-in signal emission path and the second nuclear magnetic signal processing circuit are respectively connected to the second radio frequency switch and switch to work through the second radio frequency switch;

[0035] The lock-in signal emission path and the second radio frequency switch are connected between the digital-to-analog conversion module of the main control board and the lock-in coil;

[0036] The second nuclear magnetic 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 lock-in coil.

[0037] In one embodiment, the second nuclear magnetic signal processing circuit includes: a second filter circuit and a second low-noise amplifier circuit;

[0038] The second filter circuit is used to filter the second nuclear magnetic signal induced by the lock-in coil;

[0039] The second low-noise amplifier circuit is used to amplify the filtered second nuclear magnetic signal.

[0040] In one embodiment, the second filter circuit is a band-pass filter circuit or a low-pass filter circuit.

[0041] In one embodiment, the second filter circuit and the second radio frequency switch are integrated into the same module.

[0042] In one embodiment, the lock-in signal emission path and one channel of the control signal processing circuits of multiple channels are set as the same circuit;

[0043] The second nuclear magnetic signal processing circuit and one channel of the first nuclear magnetic signal processing circuits of multiple channels are set as the same circuit.

[0044] In one embodiment, the lock-in signal emission path and the control signal processing circuits of all channels are set as the same circuit;

[0045] The second nuclear magnetic signal processing circuit and the first nuclear magnetic signal processing circuits of all channels are set as the same circuit.

[0046] In one embodiment, the quantum computing system further includes: a first resonant circuit and a second resonant circuit;

[0047] The first resonant circuit is connected between the first RF switch and the control coil, and between the first RF switch and the probe;

[0048] The second resonant circuit is connected between the second RF switch and the lock-in field coil.

[0049] In one embodiment, the probe, the control coil, and the lock-in field coil share the same coil.

[0050] In one embodiment, the sample module contains a sample serving as a qubit carrier and a mixed sample of the sample for lock-in field, and the mixed sample is disposed in the middle of the shared coil.

[0051] In one embodiment, the mixed sample is a mixed solution of dimethyl phosphite and hexafluorobenzene, wherein the dimethyl phosphite is the sample serving as a qubit carrier; the hexafluorobenzene is the sample for lock-in field; or

[0052] The mixed sample is a mixed solution of phosphorous acid aqueous solution and hexafluorobenzene, wherein the phosphorous acid aqueous solution is the sample serving as a qubit carrier; the hexafluorobenzene is the sample for lock-in field; or

[0053] The mixed sample is a mixed solution of trifluoroiodoethylene and acetone, wherein the trifluoroiodoethylene is the sample serving as a qubit carrier; the acetone is the sample for lock-in field.

[0054] In one embodiment, the control coil and the probe share the same coil, the lock-in field coil uses another coil, and the coil shared by the control coil and the probe is arranged adjacent to the lock-in field coil.

[0055] In one embodiment, the sample of the qubit carrier and the sample for lock-in field in the sample module are placed separately;

[0056] The sample serving as a qubit carrier is placed in the middle of the coil shared by the control coil and the probe; the sample for lock-in field is placed in the middle of the lock-in field coil.

[0057] In one embodiment, the sample serving as a qubit carrier is dimethyl phosphite or phosphorous acid aqueous solution; the sample for lock-in field is hexafluorobenzene; or

[0058] The sample serving as a qubit carrier is trifluoroiodoethylene; the sample for lock-in field is acetone.

[0059] In one embodiment, the quantum computing system further includes: a shimming current source and at least one set of shimming coils electrically connected to the shimming current source;

[0060] The magnet includes two permanent magnets and a magnetic yoke disposed on the permanent magnets;

[0061] The shimming coils are disposed between the two permanent magnets and are used for actively shimming the magnetic field generated by the magnet.

[0062] In a second aspect, an embodiment of the present invention provides a nuclear magnetic resonance quantum computer, including: a quantum computing software module and the 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 technical solutions provided by the embodiments of the present invention at least include:

[0065] The quantum computing system and the nuclear magnetic resonance quantum computer provided by the embodiments of the present invention abandon the existing temperature control module, and emit a lock field signal through the lock field coil and sense the second nuclear magnetic signal to realize the automatic calibration of the frequency of the control signal. Even when the ambient temperature of the quantum computing system changes, it is possible to quickly and accurately calibrate the frequency of the control signal, improve the quantum computing efficiency of the quantum computing system, and avoid the problems of long temperature control time, low efficiency, and occupation of physical space caused by using a temperature control module to control the temperature of the magnet in the prior art, making the structure of the quantum computing system more compact, the integration degree higher, and the occupied space smaller.

[0066] In one embodiment, the probe, the control coil, and the lock field coil are implemented by one coil, which can realize the transceiver of multiple signals and has the advantages of simple and compact structure and higher integration degree.

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

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

[0069] Other features and advantages of the present invention will be set forth in the following description, and in part will be obvious from the description, or may be learned by practice of the present invention. The objectives and other advantages of the present invention may be realized and attained by the structure particularly pointed out in the written description, claims, as well as the appended drawings.

[0070] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0071] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention, but do not constitute a limitation to the present invention. In the drawings:

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

[0073] Figure 2 is a schematic molecular structure diagram of dimethyl phosphite (C 2 H 7 O 3 P) in an embodiment of the present invention;

[0074] Figure 3 is a schematic diagram of the relevant circuit of the quantum computing system in the first embodiment of the present invention;

[0075] Figure 4 is a schematic diagram of the relevant circuit of the quantum computing system in the second embodiment of the present invention;

[0076] Figure 5 is a schematic diagram of the relevant circuit of the quantum computing system in the third embodiment of the present invention;

[0077] Figure 6 is a schematic structural diagram of a nuclear magnetic resonance quantum computer in an embodiment of the present invention.

[0078] Explanation of the Reference Numerals:

[0079] 100, quantum computing system;

[0080] 200, quantum computing software module;

[0081] 1. Magnet; 2. Sample module; 3. Main control board; 4. Probe; 5. Control coil; 6. Shimming coil; 7. Homogeneous field coil; 8. Homogeneous field current source; 9. Programmable logic device; 10. Digital-to-analog conversion module; 11. Analog-to-digital conversion module; 12. Control signal processing circuit; 13. First nuclear magnetic signal processing circuit; 14. First radio frequency switch; 15. Power amplification circuit; 16. First filter circuit; 17. First low-noise amplification circuit; 18. Shimming signal transmission path; 19. Second nuclear magnetic signal processing circuit; 20. Second radio frequency switch; 21. Second filter circuit; 22. Second low-noise amplification circuit; 23. First resonant circuit; 24. Second resonant circuit. Detailed implementation manners

[0082] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0083] The quantum computing system provided by the embodiment of the present invention, with reference to Figure 1 as shown, includes: a magnet 1, a sample module 2, a main control board 3, a probe 4, a control coil 5, and a shimming coil 6; wherein:

[0084] The sample module 2 contains a sample serving as a quantum bit carrier and a sample for shimming; the sample serving as a quantum bit carrier and the sample for shimming are arranged in the magnetic field of the magnet 1;

[0085] The probe 4, the control coil 5, and the shimming coil 6 are connected to the main control board 3 and are arranged between the main control board 3 and the sample module 2;

[0086] The control coil 5 is configured to emit radio frequency pulses of at least one frequency corresponding to the control signal according to the control signal sent by the main control board 3;

[0087] The probe 4 is configured to sense a first nuclear magnetic signal when the atomic nuclei serving as quantum bits in the sample serving as a quantum bit carrier undergo nuclear magnetic resonance;

[0088] The shimming coil 6 is configured to emit radio frequency pulses for calibrating the frequency of the control signal according to the shimming signal sent by the main control board 3 and sense a second nuclear magnetic signal when the atomic nuclei for shimming in the sample for shimming undergo nuclear magnetic resonance;

[0089] The main control board 3 is used to generate and send a lock-in signal when quantum computing is not in progress, demodulate the second nuclear magnetic signal corresponding to the lock-in signal returned by the lock-in coil 6, calibrate the frequency of the control signal for manipulating the quantum bit and save it; when quantum computing is in progress, generate and send the control signal according to the calibrated frequency of the control signal, and receive and demodulate the first nuclear magnetic signal corresponding to the control signal returned by the probe 4.

[0090] In one embodiment, the above-mentioned magnet 1 includes two permanent magnets and a magnetic yoke iron arranged on the permanent magnets; by finely adjusting the structure of the permanent magnets, a high-uniformity magnetic field can be generated, and the intensity of the magnetic field is, for example, 1 tesla, and the uniformity is, for example, 10 ppm (in the range where both the diameter and the height are 5 mm).

[0091] In one embodiment, the above-mentioned quantum computing system may further include: a shimming current source 8 and at least one set of shimming coils 7 electrically connected to the shimming current source 8; the shimming coils 7 are arranged between the two permanent magnets, and the shimming coils 7 are used for actively shimming the magnetic field generated by the magnet 1.

[0092] Due to factors such as processing accuracy, the magnetic field uniformity generated by the magnet 1 made of permanent magnet material still cannot meet the requirements of quantum computing (even if these permanent magnets have undergone very careful passive shimming), so it is necessary to use shimming coils with different shapes carrying current to generate a compensating magnetic field to achieve superposition with the magnetic field of the magnet 1 and finally obtain a magnetic field with higher uniformity.

[0093] Refer to Figure 1 As shown, there are multiple sets of shimming coils 7, and each set of shimming coils 7 is symmetrically arranged on the inner sides of the two permanent magnets from left to right. For example, there are a total of 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.

[0094] In specific implementation, the above-mentioned probe 4, control coil 5, and lock-in coil 6 can be realized by the same coil, or can be separately set as multiple different coils. The embodiments of the present invention do not limit this.

[0095] For example, the probe 4, control coil 5, and lock-in coil 6 can share the same coil ( Figure 1 This is the case shown schematically). At this time, the sample module contains a mixed sample of a sample serving as a quantum bit carrier and a sample for lock-in, and the mixed sample is arranged in the middle of the shared coil. In other words, the shared coil is sleeved outside the mixed sample.

[0096] In one embodiment, the above-mentioned mixed sample is a mixed solution of dimethyl phosphite (or phosphorous acid aqueous solution) and hexafluorobenzene, wherein dimethyl phosphite (or phosphorous acid aqueous solution) is the sample serving as a quantum bit carrier; the hexafluorobenzene is the sample for lock-in;

[0097] Optionally, in the mixed sample, the volume ratio of the above-mentioned dimethyl phosphite and hexafluorobenzene is 7:3.

[0098] In another embodiment, the above-mentioned mixed sample is a mixed solution of trifluoroiodoethylene and acetone, wherein trifluoroiodoethylene is a sample serving as a qubit carrier; acetone is a sample for field locking.

[0099] Optionally, in the mixed sample, the volume ratio of trifluoroiodoethylene (C 2 F 3 I) and acetone (C 3 H 6 O) is 7:3.

[0100] It can be understood that for different numbers of qubits, corresponding samples can be selected accordingly, and the present application does not limit this.

[0101] For another example, the probe 4 and the control coil 5 share the same coil, and the field locking coil uses another coil ( Figure 1 this situation is not shown), and the coil shared by the control coil and the probe is arranged adjacent to the field locking coil. Correspondingly, the sample of the qubit carrier and the sample for field locking in the sample module are placed separately; the sample serving as the qubit carrier is placed in the middle of the coil shared by the control coil and the probe, and the sample for field locking is placed in the middle of the field locking coil.

[0102] In the above situation, similarly, the sample serving as the qubit carrier is dimethyl phosphite or phosphorous acid aqueous solution; correspondingly, the sample for field locking is hexafluorobenzene.

[0103] For another example, the sample serving as the qubit carrier is trifluoroiodoethylene; the sample for field locking is acetone.

[0104] The embodiments of the present invention do not limit which specific sample is used as the carrier of the qubit and which is used as the shimming sample, and the above are only specific examples.

[0105] Regardless of whether the probe 4, the control coil 5, and the field locking coil 6 are set to be the same coil or are separately provided as multiple coils, the working periods of these coils for transmitting and receiving signals are staggered, and there is a sequential relationship in time sequence.

[0106] For the field locking coil 6, its working period is the period when the control coil 5 and the probe 4 are both not working. In other words, when transmitting the control signal and detecting the first nuclear magnetic signal using the probe 4, the field locking coil 6 is not working. Only when the system does not need to transmit the radio frequency pulse corresponding to the control signal using the control coil 5 and detect the first nuclear magnetic signal using the probe 4, the field locking coil 6 will work.

[0107] For the control coil 5, it only works when the system needs to transmit a control signal, so as to transmit a radio frequency pulse for exciting the atomic nuclei serving as qubits in the hybrid sample.

[0108] For the probe 4, it only senses the first nuclear magnetic signal (also a kind of radio frequency signal) of nuclear magnetic resonance of the qubits after the control coil 5 finishes transmitting the control signal.

[0109] In one embodiment, when the above-mentioned probe 4, control coil 5 and field locking coil 6 use the same coil, this way of sharing the same coil can achieve the transceiver of multiple signals, and at the same time has the advantages of simple and compact structure and higher integration.

[0110] In one embodiment, the above-mentioned main control board 3, referring to Figure 1 as shown, specifically includes: a programmable logic device 9, a digital-to-analog conversion module 10 and an analog-to-digital conversion module 11. The programmable logic device 9 is respectively connected to the digital-to-analog conversion module 10 and the analog-to-digital conversion module 11; wherein:

[0111] The programmable logic device 9 is used for modulating and generating the control signal and the field locking signal, and demodulating the second nuclear magnetic signal returned by the field locking coil 6 and the first nuclear magnetic signal returned by the probe 4.

[0112] The above-mentioned programmable logic device 9 can be a field programmable gate array (FPGA, Field Programmable Gate Array), a complex programmable logic device (CPLD, Complex Programmable Logic Device), an erasable programmable logic device (EPLD, Erasable Programmable Logic Device), etc.

[0113] The digital-to-analog conversion module (DAC, Digital-to-Analog Converter) 10 is used for converting the control signal or the field locking signal from a digital signal to an analog signal, and converting it into a corresponding analog signal for further sending to the control coil 5 or the field locking coil 6.

[0114] The programmable logic device 9 generates the control signal and the field locking signal in digital form, and through the conversion from a digital signal to an analog signal, it can be converted into a corresponding analog signal.

[0115] The analog-to-digital conversion module (ADC, Analog-to-Digital Converter) 11 is used for converting the second nuclear magnetic signal returned by the field locking coil 6 and the first nuclear magnetic signal returned by the probe 4 from an analog signal to a digital signal, and converting it into a corresponding digital signal and sending it to the programmable logic device 9.

[0116] The second nuclear magnetic signal returned by the lock-in coil 6 and the first nuclear magnetic signal returned by the probe 4 are analog signals, and the analog-to-digital conversion module 11 converts both into corresponding digital signals and returns them to the FGPA module 9.

[0117] The programmable logic device 9 generates modulation radio frequency signals (control signals and lock-in signals) that meet the requirements of quantum computing, as well as receives and demodulates radio frequency signals (the first nuclear magnetic signal and the second nuclear magnetic signal). In the embodiment of the present invention, both the modulation and demodulation of the radio frequency signal are implemented by the programmable logic device 9, without adding an additional hardware modem.

[0118] In order to implement the manipulation of each qubit, the resonance radio frequency frequency corresponding to each qubit is set in a different frequency band. Therefore, it is required that the programmable logic device 9 can generate multiple radio frequency signals (control signals) with different frequencies, and also needs to be able to receive and demodulate radio frequency signals with different frequencies (the first nuclear magnetic signal).

[0119] Taking dimethyl phosphite as the physical qubit carrier for quantum computing as an example, Figure 2 is the molecular structure diagram of dimethyl phosphite (C 2 H 7 O 3 P). It can be seen from this molecular structure diagram that there are 7 hydrogen (H) atoms and 1 phosphorus (P) atom in the dimethyl phosphite molecule. A hydrogen nucleus is directly coupled to the phosphorus nucleus on this molecular structure. The nuclear magnetic moments of this phosphorus nucleus and the hydrogen nucleus coupled to it can be used as the carriers of two physical qubits for quantum computing. In other words, in a magnetic field, the phosphorus nucleus and the hydrogen nucleus on the molecule become two two-level systems due to Zeeman splitting, and they are respectively used as two qubits.

[0120] By respectively manipulating the hydrogen nucleus and the phosphorus nucleus directly coupled by radio frequency electromagnetic waves, their nuclear magnetic moments can be used for quantum computing gate operations, and their final states can be read (obtained by inducing and demodulating the first nuclear magnetic signal).

[0121] Another example is that the fluorine nucleus in hexafluorobenzene (C 6 F 6 ) in the sample for lock-in, or the hydrogen nucleus in acetone (C 3 H 6 O), is excited by the radio frequency signal emitted by the lock-in coil 6, and the second nuclear magnetic signal is induced by this lock-in coil 6 and transmitted to the main control board 3 for demodulation.

[0122] The principle of field locking is to periodically excite the nuclei used for field locking (such as the fluorine nuclei in the aforementioned hexafluorobenzene or the hydrogen nuclei in acetone) during the time when quantum computing is not being performed, and to read the state of the nuclei used for field locking by sensing the second nuclear magnetic signal.

[0123] In the sample module, whether the sample serving as the qubit carrier and the sample used for field locking are placed separately or together as a mixed sample, under the conditions of the same magnetic field strength and temperature, the ratio of the nuclear magnetic resonance frequency of the nuclei serving as the qubit carrier to the nuclear magnetic resonance frequency of the nuclei used for field locking remains unchanged. Therefore, regardless of how the external temperature and magnetic field change, since the nuclei serving as the qubit carrier and the nuclei used for field locking are always under the same magnetic field strength and temperature, the ratio of their nuclear magnetic resonance frequencies remains unchanged. For example, in a mixed solution of dimethyl phosphite and hexafluorobenzene, the ratio of the nuclear magnetic resonance frequencies of the hydrogen nuclei and the fluorine nuclei remains unchanged regardless of how the external magnetic field strength and temperature change. Similarly, the ratio of the nuclear magnetic resonance frequencies of the phosphorus nuclei and the fluorine nuclei does not change.

[0124] However, in a quantum computing system, since the magnetic field strength of magnet 1 is sensitive to temperature, a change in the external temperature may bring about a change in the magnetic field strength, and a change in the magnetic field strength will further cause a change in the nuclear magnetic resonance frequencies of the nuclei serving as the qubit carrier and the nuclei used for field locking themselves (although the ratio between the two does not change).

[0125] Based on the above principle, the field locking signal and the second nuclear magnetic signal can be used to calibrate the frequency of the control signal to be sent in the future.

[0126] When quantum computing is not being performed, the field locking 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 when the next field locking signal is transmitted, it can be automatically adjusted to the latest frequency of the field locking signal (i.e., perform a frequency compensation). Also, since there is a fixed ratio relationship with the frequency of the nuclei serving as the qubit carrier, if the control signal needs to be transmitted at the next moment instead of the field locking signal, then based on the latest frequency of the field locking signal, the corresponding frequency of the control signal can be obtained, thereby achieving automatic calibration of the frequency of the control signal.

[0127] The latest frequency value of the field locking signal obtained by periodically sending the field locking signal is saved so that when the control signal needs to be sent, the corresponding latest frequency value of the control signal can be calculated based on this latest frequency value.

[0128] The embodiment of the present invention abandons the existing temperature control module, and realizes the automatic calibration of the frequency of the control signal by transmitting the lock-in field signal and sensing the second nuclear magnetic signal. Even when the ambient temperature changes, it can quickly and accurately calibrate the frequency of the control signal, avoiding the problems of long temperature control time, low efficiency, and occupation of physical space 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, the structure of the quantum computing system is more compact, the integration degree is higher, and the occupied space is smaller.

[0129] In one embodiment, for the above-mentioned quantum computing system, refer to Figure 1 As shown, it further includes: at least one first radio frequency switch 14, a control signal processing circuit 12 for at least one channel, and a first nuclear magnetic signal processing circuit 13 for at least one channel corresponding to the control signal processing circuit 12 for at least one channel respectively; wherein:

[0130] Each control signal processing circuit 12 and the corresponding first nuclear magnetic signal processing circuit 13 are respectively connected to a first radio frequency switch 14, and switch to work through the first radio frequency switch 14;

[0131] The control signal processing circuit 12 for at least one channel and at least one first radio frequency switch 14 are connected between the digital-to-analog conversion module 10 of the main control board 3 and the control coil 5;

[0132] The first nuclear magnetic signal processing circuit 13 for at least one channel 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;

[0133] The first radio frequency switch 14, when the control signal is transmitted, conducts the control coil 5, the control signal processing circuit 12 and the main control board 3; when the control signal is turned off and the lock-in field signal is not transmitted, conducts the probe 4, the first nuclear magnetic signal processing circuit 13 and the main control board 3.

[0134] The first radio frequency switch 14 is responsible for switching between the control signal processing circuit 12 and the first nuclear magnetic signal processing circuit 13.

[0135] In the case where there are multiple control signal processing circuits 12, it is because there are multiple atomic nuclei serving as qubits in the sample serving as the qubit carrier, and multiple control signal processing circuits 12 are required to process the corresponding control signals respectively. For example, in the aforementioned example where the mixed sample is dimethyl phosphite and hexafluorobenzene, the phosphorus atomic nucleus and the hydrogen atomic nucleus are used as two qubits respectively, then two different control signal processing circuits 12 can be set respectively to process the control signals of different qubits (the frequencies of the control signals are different from each other).

[0136] In one embodiment, when control signals of different frequencies are sent successively, the control signal processing circuits 12 of the above-mentioned multiple different channels can also be implemented by sharing one path. Correspondingly, the first nuclear magnetic signal processing circuits 13 of the above-mentioned multiple different channels are also implemented by sharing one path. That is, the control signals of different frequencies are processed by the same channel control signal processing circuit 12. Correspondingly, the first nuclear magnetic signals of different frequencies can also be processed by the first nuclear magnetic signal processing circuit 13 of the same channel (the frequencies of the control signal and the corresponding first nuclear magnetic signal are the same).

[0137] Further, the control signal processing circuit 12 specifically includes: a power amplifier circuit 15; the power amplifier circuit 15 is used to amplify the control signal sent by the main control board 3;

[0138] The power amplifier circuit 15 is responsible for amplifying the control signal to an appropriate intensity. In the embodiment of the present invention, the power amplifier circuit can have a gain of 56 dB and a maximum power of 50 W, for example, in the range of 10 - 60 MHz.

[0139] In one embodiment, a filter circuit (not shown in the figure) can also be provided on the control signal processing circuit 12. If a filter circuit needs to be provided, it needs to be placed before the power amplifier circuit 15 (that is, the control signal is filtered first and then amplified). Or, when the power amplifier circuit 15 is a multi-stage amplifier circuit, the filter circuit can be provided between the multi-stage amplifier circuits, for example, between two-stage amplifier circuits. Figure 1

[0140]

[0141]

[0142] Correspondingly, the first nuclear magnetic signal processing circuit 13 specifically includes: a first filter circuit 16 and a first low-noise amplifier circuit 17;

[0143] The first filter circuit 16 is used to filter the first nuclear magnetic signal induced by the probe 4;

[0144]

[0145] For the loop of the first nuclear magnetic signal, the first nuclear magnetic 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 provided between the multi-stage amplifier circuits, for example, between two-stage amplifier circuits.After being amplified by the first low-noise amplifier circuit 17, the first nuclear magnetic signal can be amplified to the range of 1 mV - 1 V.

[0145] Optionally, the first filter circuit 16 may be a band-pass filter circuit or a low-pass filter circuit.

[0146] In one embodiment, the first filter circuit 16 and the first RF switch 14 are integrated into the same module.

[0147] In one embodiment, the quantum computing system, with reference to Figure 1 As shown, it may also include: a lock signal transmission path 18, a second nuclear magnetic signal processing circuit 19 and a second radio frequency switch 20;

[0148] The lock signal transmission path 18 and the second nuclear magnetic signal processing circuit 19 are respectively connected to the second radio frequency switch 20, and work is switched by the second radio frequency switch 20;

[0149] The lock signal transmission path 18 and the second RF switch 20 are connected between the digital-to-analog conversion module 10 of the main control board 3 and the lock coil 6;

[0150] 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 of the main control board 3 and the locking coil 6 .

[0151] In one embodiment, since the transmitted lock signal does not need to be as high quality as the control signal, the lock signal transmission path 18 may not be provided with any functional circuit (no filtering and amplification, etc.), and only serves the purpose of transmitting the lock signal.

[0152] Of course, in an optional embodiment, the lock signal transmission path 18 may also be provided with functional circuits such as a filter circuit and an amplifier circuit, which are similar to the structure of the control signal processing circuit 12 and will not be described in detail here.

[0153] The second RF switch 20 is responsible for switching the lock signal transmission path 18 and the second nuclear magnetic signal processing circuit 19. The lock signal is first transmitted, and after the transmission is completed, it is switched to the second nuclear magnetic signal processing circuit 19, so that the second nuclear magnetic signal induced by the lock coil 6 can be smoothly processed by the second nuclear magnetic signal processing circuit 19 and then returned to the main control board 3.

[0154] In one embodiment, the second nuclear magnetic signal processing circuit 19 specifically includes: a second filtering circuit 21 and a second low-noise amplifier circuit 22;

[0155] The second filter circuit 21 is used to filter the second nuclear magnetic signal induced by the lock coil 6;

[0156] The second low-noise amplifier circuit 22 is used to amplify the filtered second nuclear magnetic signal.

[0157] The function of the second filtering circuit 21 is similar to that of the aforementioned first filtering circuit 16, and the function of the second low-noise amplification circuit 22 is similar to that of the aforementioned first low-noise amplification circuit 17, which will not be elaborated here.

[0158] In one embodiment, the second filtering circuit 21 and the second radio frequency switch 20 are integrated into the same module.

[0159] In one embodiment, the lock field signal transmission path 18 and a certain channel in the control signal processing circuits 12 of multiple channels can be set to the same circuit;

[0160] Correspondingly, a certain channel in the second nuclear magnetic signal processing circuit 19 and the first nuclear magnetic signal processing circuits 13 of multiple channels can also be set to the same circuit.

[0161] In one embodiment, the above-mentioned quantum computing system, referring to Figure 1 as shown, further includes: a first resonant circuit 23 and a second resonant circuit 24; wherein:

[0162] The first resonant circuit 23 is connected between the first radio frequency switch 14 and the control coil 5, and between the first radio frequency switch 14 and the probe 4;

[0163] The second resonant circuit 24 is connected between the second radio frequency switch 20 and the lock field coil 6.

[0164] 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. And the first nuclear magnetic signal of the corresponding frequency is efficiently returned to the programmable logic device 9 completely. Without the first resonant circuit 23, when the control signal enters the control coil 5, due to reasons such as impedance mismatch, resonance may not be completed, and most of the signals are reflected back. In this way, the control signal cannot enter the control coil completely and efficiently, and thus the radio frequency pulse cannot be injected into the corresponding sample completely and efficiently, or even if it is injected, the first nuclear magnetic signal sensed by the probe 4 may not be returned completely.

[0165] Since the transmitted control signal and the received first nuclear magnetic signal are of the same frequency and their resonance points are the same, the same resonant circuit is required for reception as that used for the transmitted control signal.

[0166] For the first nuclear magnetic signals of different frequencies, the same first resonant circuit 23 can receive first nuclear magnetic signals of different frequencies through different inductors, enabling the probe 4 to transmit first nuclear magnetic signals of different frequencies back to the programmable logic device 9 through one resonant circuit.

[0167] The function of the second resonance circuit 24 is similar to that of the first resonance circuit 23, but it targets the lock-in signal and the second nuclear magnetic signal of a single frequency. The specific functions and principles will not be elaborated here.

[0168] To better illustrate the structures and functions of the various parts of the above-mentioned quantum computing system provided by the embodiments of the present invention, the following will be further described with several specific embodiments.

[0169] Embodiment 1:

[0170] The structure of Embodiment 1 of the present invention can be referred to Figure 3 as shown. The quantum computing system includes: a magnet ( Figure 3 not shown in Figure 3 ), a sample module ( Figure 3 not shown in Figure 3 ), a shim current source and shim coils (not shown in

[0171] ), a main control board, a probe, control coils and lock-in coils, a control signal processing circuit, a first nuclear magnetic signal processing circuit, a first RF switch, a lock-in signal transmission path, a second nuclear magnetic signal processing circuit, a second RF switch, a first resonance circuit and a second resonance circuit, etc. Among them, the probe, control coils and lock-in coils are the same coil. The structures and functions of the magnet, sample module, shim current source and shim coils are the same as those in the foregoing embodiments and will not be elaborated here. The following will describe 2 H 7 O 3 P) and hexafluorobenzene (C 6 F 6 ). Among them, the hydrogen (H) nuclei and phosphorus (P) nuclei in dimethyl phosphite serve as carriers of quantum bits, and the fluorine nuclei in hexafluorobenzene serve as nuclei for lock-in.

[0172] The frequency of the control signal for manipulating the hydrogen nuclei is the same as the frequency of the corresponding first nuclear magnetic signal. Similarly, the frequency of the control signal for manipulating the phosphorus nuclei is the same as the frequency of the corresponding first nuclear magnetic signal. However, the frequency of the control signal for manipulating the hydrogen nuclei is not the same as the frequency of the control signal for manipulating the phosphorus nuclei.

[0173] The frequency of the lock-in signal for manipulating the fluorine nuclei is not the same as the frequencies of the control signals for manipulating hydrogen and phosphorus, but the lock-in signal is the same as the frequency of the corresponding second nuclear magnetic signal.

[0174] In Figure 3 , the letter H is used to represent the hydrogen nuclei, the letter P is used to represent the phosphorus nuclei, and the letter F is used to represent the fluorine nuclei.

[0175] In the main control board, an FPGA module, an ADC and a DAC connected to the FPGA module are included.

[0176] The DAC has two outputs, respectively corresponding to a control signal processing circuit (including a power amplification circuit) and a lock field signal transmitting path;

[0177] A power amplification circuit is provided in the control signal processing circuit;

[0178] The lock field signal transmitting path is connected between the DAC and the second radio frequency switch.

[0179] The ADC has two inputs. One input comes from a second nuclear magnetic signal processing circuit (including a low-noise amplification & band-pass filtering circuit), and the other input comes from any one of the first nuclear magnetic signal processing circuits of two channels (each channel includes a low-noise amplification & band-pass filtering circuit); the first nuclear magnetic signal processing circuits of these two channels are respectively used to process the first nuclear magnetic signals returned by the excited hydrogen atomic nuclei and phosphorus atomic nuclei. Since the first nuclear magnetic signals corresponding to the hydrogen atomic nuclei and the phosphorus atomic nuclei are not generated simultaneously, at the same moment, only the first nuclear magnetic signal of one of the channels returns to the main control board. Therefore, the first nuclear magnetic signal processing circuits of the two channels can share the input channel of the same ADC. Figure 3 In it, the first nuclear magnetic signal processing circuits of the two channels are labeled as: the first nuclear magnetic signal processing circuit (H&P).

[0180] In the first embodiment, the control signals corresponding to the hydrogen atomic nuclei and the phosphorus atomic nuclei share the same control signal processing circuit, which is labeled as: the control signal processing circuit (H&P) in Figure 3 On the one hand, it is because the sending and transmission of the control signals of the hydrogen atomic nuclei and the phosphorus atomic nuclei are also time-division (for example, first excite the hydrogen atoms, and then excite the phosphorus atoms, with a sequence), and they will not be carried out simultaneously. On the other hand, since the bandwidth of the power amplification circuit is relatively wide, although the frequencies of the control signals of the hydrogen atomic nuclei and the phosphorus atomic nuclei are different, the two can share the same power amplification circuit.

[0181] In the first embodiment, the control signals and the first nuclear magnetic signals of the hydrogen atomic nuclei and the phosphorus atomic nuclei are all processed by the same resonance circuit (the first resonance circuit), while the lock field signal and the second nuclear magnetic signal of the fluorine atomic nuclei are processed by another resonance circuit (the second resonance circuit). These two resonance circuits can both be LC resonance circuits for example.

[0182] Embodiment Two:

[0183] The structure of the second embodiment of the present invention can be referred to Figure 4 As shown, this quantum computing system includes: a magnet ( Figure 4not shown), sample module ( Figure 4 not shown), shimming current source and shimming coil (in Figure 4 not shown), main control board, probe, control coil and lock-in coil, control signal processing circuit, first nuclear magnetic signal processing circuit, first RF switch, lock-in signal transmission path, second nuclear magnetic signal processing circuit, second RF switch, first resonance circuit and second resonance circuit, etc. Among them, the probe, control coil and lock-in coil are the same coil. The structures and functions of the magnet, sample module, shimming current source and shimming coil are the same as those in the previous embodiment and will not be elaborated here. The following will Figure 4 describe the modules shown.

[0184] In the second embodiment, similar to the first embodiment, the mixed sample in the sample module is also a mixed solution of dimethyl phosphite (C 2 H 7 O 3 P) and hexafluorobenzene (C 6 F 6 ). In Figure 4 , the letter H is used to represent the hydrogen nucleus, the letter P is used to represent the phosphorus nucleus, and the letter F is used to represent the fluorine nucleus.

[0185] Different from the first embodiment, in the second embodiment, the lock-in signal transmission path corresponding to the fluorine nucleus and the control signal processing circuit corresponding to the hydrogen nucleus share the same circuit, which is labeled as the control signal processing circuit & lock-in signal transmission path in Figure 4 ; the second nuclear magnetic signal processing circuit corresponding to the fluorine nucleus and the first nuclear magnetic signal processing circuit corresponding to the hydrogen nucleus share the same circuit, which is labeled as: the first nuclear magnetic signal processing circuit (H) & the second nuclear magnetic signal processing circuit (F) in Figure 4 . Referring to Figure 4 shown, this circuit includes a low-noise amplification & band-pass filtering circuit.

[0186] For the control signal processing circuit corresponding to the phosphorus nucleus and the first nuclear magnetic signal processing circuit, they are separately arranged from the signal processing circuits of the aforementioned fluorine nucleus and hydrogen nucleus.

[0187] When the control signal processing circuit corresponding to the hydrogen nucleus and the lock-in signal transmission path corresponding to the fluorine nucleus share the same circuit, referring to Figure 4 shown, this circuit includes a power amplification circuit.

[0188] The specific structures of the first nuclear magnetic signal processing circuit and the second nuclear magnetic signal processing circuit are similar to those in the first embodiment and will not be elaborated here.

[0189] Since the lock field signal corresponding to the fluorine nucleus and the control signal corresponding to the hydrogen nucleus also have different timings and are not generated and transmitted at the same time, the control signal processing circuit corresponding to the hydrogen nucleus and the lock field signal transmission path corresponding to the fluorine nucleus can share the same circuit.

[0190] The first radio frequency switch is used to switch the emission of the phosphorus nucleus control signal and the reception of the first nuclear magnetic field signal of the phosphorus nucleus.

[0191] The second radio frequency switch is used to switch the emission of the hydrogen nucleus control signal and the reception of the first nuclear magnetic signal of the hydrogen nucleus; and is used to switch the emission of the fluorine nucleus lock field signal and the reception of the second nuclear magnetic signal of the fluorine nucleus.

[0192] In the second embodiment, the first resonant circuit and the second resonant circuit are also used to process the radio frequency signal of phosphorus nuclei and the radio frequency signal of hydrogen and fluorine nuclei respectively.

[0193] Embodiment three:

[0194] The structure of the third embodiment of the present invention can be referred to Figure 5 As shown, the quantum computing system includes: a magnet ( Figure 5 Not shown), sample module ( Figure 5 ), shim current source and shim coil (not shown in Figure 5 The present invention relates to a method for manufacturing a nuclear magnetic resonance image processing device, a nuclear magnetic resonance image processing device, a first nuclear magnetic resonance image processing device, a first radio frequency switch, a field lock signal transmission path, a second nuclear magnetic resonance image processing circuit, a second radio frequency switch (which is the same device as the first radio frequency switch and is therefore not independently illustrated), a first resonant circuit and a second resonant circuit (which is the same circuit as the first resonant circuit and is therefore not independently illustrated), etc., wherein the probe, the control coil and the field lock coil are the same coil, and the structures and functions of the magnet, the sample module, the shim current source and the shim coil are the same as those in the aforementioned embodiment and are not described in detail herein.

[0195] The difference from the first and second embodiments is that the control signal processing circuits and the lock signal transmission paths of all channels are implemented by the same circuit. Figure 5 The structure of the control signal processing circuit of only one channel is shown in the figure, which is marked as: control signal processing circuit (F) & lock signal transmission path (H), and the circuit includes a power amplifier circuit. Since the first nuclear magnetic signal processing circuit and the second nuclear magnetic signal processing circuit of multiple channels are also implemented by the same circuit, Figure 5 Only the structure of the first nuclear magnetic signal processing circuit of one channel is illustrated, which is marked as: first nuclear magnetic signal processing circuit (F) & second nuclear magnetic signal processing circuit (H), which includes a low-noise amplifier & bandpass filter circuit.

[0196] Moreover, the functions of the first radio frequency switch and the second radio frequency switch are also implemented by the same radio frequency switch. Only the first radio frequency switch is shown in Figure 5 .

[0197] In the third embodiment, the functions of the first resonance circuit and the second resonance circuit are also implemented by the same circuit. Therefore, Figure 5 only the first resonance circuit is shown in. One end of the first resonance circuit is grounded.

[0198] Different from the first and second embodiments, the mixed sample in the sample module of the third embodiment is a mixed solution of vinylidene fluoride (C 2 F 3 I) and acetone (C 3 H 6 O). In a magnetic field, the three fluorine nuclei on the vinylidene fluoride (C 2 F 3 I) molecule become three two-level systems due to Zeeman splitting, and they are respectively used as three qubits. The hydrogen atoms on acetone are used for field locking. In Figure 5 , the letter H represents the hydrogen nucleus, and the letter F represents the fluorine nucleus.

[0199] Whether it is the control signal for the three fluorine atoms of vinylidene fluoride as three qubits or the field locking signal for the hydrogen atoms on acetone, their emission timings are separated. Similarly, for the first nuclear magnetic signal of the three fluorine atoms and the second nuclear magnetic signal corresponding to the hydrogen atoms, their reception timings are also separated.

[0200] In the third embodiment, it can be seen from Figure 5 that the ADC has only one input and the DAC also has only one output.

[0201] Compared with the first and second embodiments, the third embodiment has higher hardware integration, a more compact structure, lower hardware costs, and is more conducive to the miniaturization of the overall system.

[0202] Based on the same inventive concept, the embodiments of the present invention also provide a nuclear magnetic resonance quantum computer. As shown in Figure 6 , it includes: a quantum computing software module 200 and the quantum computing system 100 provided in the foregoing embodiments;

[0203] Among them, the quantum computing software module 200 is communicatively connected to the main control board of the quantum computing system 100.

[0204] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A quantum computing system, characterized in that: include: Magnet, sample module, main control board, probe, control coil and lock coil; among which: The sample module is equipped with a sample as a quantum bit carrier and a sample for locking the field; the sample as a quantum bit carrier and the sample for locking the field are arranged in the magnetic field of the magnet; The probe, control coil and lock coil are connected to the main control board and arranged between the main control board and the sample module; The control coil is used to transmit a radio frequency pulse of at least one frequency corresponding to the control signal sent by the main control board; The probe is used to sense a first nuclear magnetic signal when a nucleus as a quantum bit in the sample as a quantum bit carrier undergoes nuclear magnetic resonance; The locking coil is used to transmit a radio frequency pulse for calibrating the frequency of the control signal according to the locking signal sent by the main control board, and to sense a second nuclear magnetic signal when nuclear magnetic resonance occurs between the locking sample and the atomic nucleus used for locking; The main control board is used to generate and send the lock field signal when quantum computing is not performed, and demodulate the second nuclear magnetic signal corresponding to the lock field signal returned by the lock field coil, calibrate the frequency of the control signal used to manipulate the quantum bit and save it; when quantum computing is performed, generate and send the control signal according to the calibrated frequency of the control signal, receive and demodulate the first nuclear magnetic signal corresponding to the control signal returned by the probe.

2. The quantum computing system according to claim 1, characterized in that The main control board includes: a programmable logic device, a digital-to-analog conversion module and an analog-to-digital conversion module, wherein the programmable logic device is connected to the digital-to-analog conversion module and the analog-to-digital conversion module respectively; wherein: The programmable logic device is used to modulate and generate the control signal and the lock signal, and to demodulate the second nuclear magnetic signal returned by the lock coil and the first nuclear magnetic signal returned by the probe; The digital-to-analog conversion module is used to convert the control signal or the lock signal into a digital-to-analog signal, and convert it into a corresponding analog signal, so as to further send it to the control coil or the lock coil; The analog-to-digital conversion module is used to convert the second nuclear magnetic signal returned by the lock coil and the first nuclear magnetic 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 according to claim 2, characterized in that Also includes: At least one first radio frequency switch, at least one channel control signal processing circuit, and at least one channel first nuclear magnetic signal processing circuit corresponding to the at least one channel control signal processing circuit; Each control signal processing circuit and the corresponding first nuclear magnetic signal processing circuit are respectively connected to a first radio frequency switch, and work is switched by 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 conversion module of the main control board and the control coil; At least one first nuclear magnetic signal processing circuit of a channel 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 RF switch turns on the control coil, the control signal processing circuit and the main control board when the control signal is transmitted; and turns on the probe, the first nuclear magnetic signal processing circuit and the main control board when the control signal is turned off and the non-lock signal is transmitted.

4. The quantum computing system according to 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 signal sent by the main control board; The first nuclear magnetic 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 signal induced by the probe; The first low-noise amplifier circuit is used to amplify the filtered first nuclear magnetic signal.

5. The quantum computing system according to claim 4, characterized in that The first filter circuit is a bandpass filter circuit or a low-pass filter circuit.

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

7. The quantum computing system according to claim 3, characterized in that In the case that the control signal processing circuit of the at least one channel is a plurality of 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 according to claim 3, characterized in that When control signals of different frequencies are sent successively, control signals of different frequencies are processed by the control signal processing circuit of the same channel, and first nuclear magnetic signal processing circuit of the same channel is used to process first nuclear magnetic signal of different frequencies.

9. The quantum computing system according to claim 3, characterized in that Also includes: A lock signal transmission path, a second nuclear magnetic signal processing circuit and a second radio frequency switch; The lock signal transmission path and the second nuclear magnetic signal processing circuit are respectively connected to the second radio frequency switch and work by switching the second radio frequency switch; The lock signal transmission path and the second radio frequency switch are connected between the digital-to-analog conversion module of the main control board and the lock coil; The second nuclear magnetic 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 locking coil.

10. The quantum computing system according to claim 9, characterized in that The second nuclear magnetic signal processing circuit includes: a second filtering circuit and a second low-noise amplifying circuit; The second filtering circuit is used to filter the second nuclear magnetic signal induced by the locking coil; The second low-noise amplifier circuit is used to amplify the filtered second nuclear magnetic signal.

11. The quantum computing system according to claim 10, characterized in that The second filter circuit is a bandpass filter circuit or a low-pass filter circuit.

12. The quantum computing system according to claim 10, characterized in that The second filtering circuit and the second radio frequency switch are integrated into the same module.

13. The quantum computing system of claim 9, wherein: The lock signal transmission path and one of the channels of the control signal processing circuits of the multiple channels are set to be the same circuit; The second nuclear magnetic signal processing circuit and one channel of the first nuclear magnetic signal processing circuit of the multiple channels are configured as the same circuit.

14. The quantum computing system of claim 9, wherein: The lock signal transmission path and the control signal processing circuits of all channels are configured as the same circuit; The second nuclear magnetic signal processing circuit and the first nuclear magnetic signal processing circuits of all channels are configured as the same circuit.

15. The quantum computing system of claim 9, wherein: Also includes: a first resonant circuit and a second resonant circuit; A first resonant circuit is connected between the first RF switch and the control coil, and between the first RF switch and the probe; The second resonant circuit is connected between the second radio frequency switch and the locking coil.

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

17. The quantum computing system of claim 16, wherein: The sample module is loaded with a mixed sample of a sample serving as a quantum bit carrier and a sample used for locking the field, and the mixed sample is arranged in the middle of a common coil.

18. The quantum computing system of claim 17, wherein: The mixed sample is a mixed solution of dimethyl phosphite and hexafluorobenzene, wherein dimethyl phosphite is a sample used as a quantum bit carrier; and hexafluorobenzene is a sample used for locking the field; or The mixed sample is a mixed solution of phosphorous acid aqueous solution and hexafluorobenzene, wherein the phosphorous acid aqueous solution is a sample used as a quantum bit carrier; and the hexafluorobenzene is a sample used for locking the field; or The mixed sample is a mixed solution of trifluoroethylene iodide and acetone, wherein trifluoroethylene iodide is a sample used as a quantum bit carrier; and the acetone is a sample used for locking the field.

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

20. The quantum computing system of claim 19, wherein: The samples of quantum bit carriers and the samples used for locking the field in the sample module 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 locking the field is placed in the middle of the locking field coil.

21. The quantum computing system of claim 20, wherein: The sample used as a quantum bit carrier is dimethyl phosphite or phosphorous acid aqueous solution; the sample used for locking the field is hexafluorobenzene; or The sample used as a quantum bit carrier is trifluoroiodoethylene; the sample used for locking the field is acetone.

22. The quantum computing system according to any one of claims 1 to 15, characterized in that: Also includes: A shim current source and at least one set of shim coils electrically connected to the shim current source; The magnet comprises two permanent magnets and a magnetic yoke iron arranged on the permanent magnets; The shimming coil is arranged between two permanent magnets and is used for actively shimming the magnetic field generated by the magnets.

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

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