Quantum bit rapid initialization method and system and superconducting quantum computer

Abstract

The invention discloses a quantum bit rapid initialization method and system and a superconducting quantum computer. The method comprises the following steps: calibrating quantum bit reading cavity frequency, excited state frequency, Raproportion oscillation between a ground state and a first excited state and Raproportion oscillation between excited states; calibrating the transverse field driving frequency of the decoration state and the transverse field driving frequency of the excitation state; quantum state evolution probabilities under different transverse field driving amplitudes are measured, and a transverse field driving parameter with the fastest initialization rate is determined; and transverse field driving parameters are applied to corresponding channels to realize rapid initialization of the quantum bits. The system comprises a waveform generator module, a combiner module, a quantum carrier module and a reading display module. The superconducting quantum computer comprises the system and executes the method. According to the invention, the equivalent coupling strength between the quantum bit and the resonant cavity can be rapidly changed, the rapid dissipation channel is constructed by using the extremely strong photon dissipation rate of the resonant cavity, and the rapid initialization of the Fluxium quantum bit is realized.

Description

Technical Field

[0001] The present invention relates to the quantum field, and in particular to a quantum bit rapid initialization method, system and superconducting quantum computer. Background Art

[0002] Superconducting quantum computers use quantum properties such as quantum superposition and entanglement to exponentially accelerate the speed of traditional computers when processing complex operations. As the basic unit of superconducting quantum computing, the choice of quantum bit design plays a vital role in the performance and scalability of superconducting quantum computers. Common types of quantum bits include transmon, Fluxonium and Xmon.

[0003] Among them, the energy difference between the energy levels of Fluxonium qubits shows a nonlinear relationship with the change of external magnetic flux. Its nonlinearity is used to optimize the geometric structure and material parameters of the superconducting loop when designing Fluxonium. At the same time, combined with external magnetic field control technology, it can effectively suppress magnetic flux quantum fluctuations and improve the coherence and stability of qubits. At the same time, good anharmonicity also makes Fluxonium qubits not easily excited to the high energy band during gate operations. Generally, the coherence time of Fluxonium can reach milliseconds. Manipulating Fluxonium qubits for scientific experiments is a complex and precise task. In this process, initializing qubits is one of the most critical links.

[0004] By correctly initializing the qubit, we can put it in the desired initial state, providing a reliable basis for subsequent operations and measurements. This accurate initialization not only helps maintain the consistency and repeatability of experimental results, but also minimizes the impact of external interference and improves the accuracy and credibility of the experiment.

[0005] There are many methods for initializing qubits at present, such as using the energy relaxation of the bit to allow it to decay to the ground state by itself. However, for Fluxonium qubits, due to their long energy relaxation time, it takes a long time for them to decay to the ground state by themselves. Another example is to add some dissipative elements during the design and processing of superconducting quantum chips to quickly put the qubit in the ground state, but this will increase the manufacturing process burden of Fluxonium qubits and affect the bit performance. The last part is to adjust the external magnetic flux to change the energy level structure of the qubit so that it is in the ground state, but the introduction of external magnetic flux signals will bring magnetic flux noise, which will increase the error in the qubit initialization process.

[0006] In summary, although there are various initialization methods for quantum bits, none of them can be directly applied to initializing Fluxonium quantum bits. Summary of the invention

[0007] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a quantum bit fast initialization method, system and superconducting quantum computer.

[0008] In order to achieve the above object, the present invention adopts the following technical solution: a method for rapid initialization of quantum bits, comprising:

[0009] S100, calibrating the quantum bit reading cavity frequency, the frequency of the excited state, the Rabi oscillation between the ground state and the first excited state, and the Rabi oscillation between the excited states;

[0010] S200, calibrating the transverse field driving frequency of the decorated state and the transverse field driving frequency of the excited state to obtain a corresponding relationship between the transverse field driving frequency and the transverse field driving amplitude;

[0011] S300, measuring the probability of quantum state ground state evolution under different transverse field driving amplitudes, and determining the transverse field driving parameter with the fastest initialization rate in combination with the corresponding relationship between the transverse field driving frequency and the transverse field driving amplitude in S200;

[0012] S400, applying the transverse field driving parameters obtained in S300 to the corresponding channel to achieve rapid initialization of the quantum bit.

[0013] Optionally, in step S100, the reading cavity frequency of the quantum bit is calibrated by a calibration device, the frequencies of the first excited state and the second excited state of the quantum bit are calibrated, the Rabi oscillation between the ground state and the first excited state of the quantum bit is calibrated, and the Rabi oscillation between the first excited state and the second excited state of the quantum bit is calibrated.

[0014] Optionally, step S200 includes:

[0015] S210, completing the transverse field driving frequency calibration of the first decoration state and the third decoration state;

[0016] S220, completing the transverse field driving frequency calibration of the first excited state and the second excited state of the quantum bit.

[0017] Optionally, step S210 includes:

[0018] S211, preparing the quantum bit to a first dressed state;

[0019] S212, based on the first decoration state, fixing the transverse field driving time, and applying transverse driving fields of different frequencies and amplitudes on the XY channel;

[0020] S213, obtaining an energy spectrum of the quantum state as it changes with frequency and driving amplitude ratio;

[0021] S214, fitting a first spectrum line with the highest probability that the quantum bit is in the ground state, to obtain the transverse field driving frequencies of the third decorated state and the first decorated state and the transverse field driving amplitudes corresponding to the transverse field driving frequencies.

[0022] Optionally, step S220 includes:

[0023] S221, exciting the quantum bit from a first excited state to a second excited state;

[0024] S222, applying the transverse field driving frequency and transverse field driving amplitude of the first and third dressed states fitted in step S214 to the XY channel of the quantum bit;

[0025] S223, obtaining the transverse field driving frequency of the quantum bit between the first excited state and the second excited state of different groups, and

[0026] Energy spectra of different groups of first and third dressed states under transverse field driving amplitudes;

[0027] S224, fitting the second spectrum line with the highest probability of the quantum bit being in the ground state to obtain the transverse field driving frequency between the first excited state and the second excited state and the corresponding transverse field driving amplitudes of the first decorated state and the third decorated state.

[0028] Optionally, step S300 includes:

[0029] S310, obtaining the transverse field driving frequencies of the first dressing state and the third dressing state and the transverse field driving frequencies between the first excited state and the second excited state corresponding to the transverse field driving amplitudes of the first dressing state and the third dressing state of different groups;

[0030] S320, measuring the quantum state ground state evolution probability for different groups of transverse field driving frequencies and amplitudes;

[0031] S321, construct the quantum system state evolution equation and cyclically solve the coupling parameters and decay rate;

[0032] S322, obtaining the transverse field driving amplitude and transverse field driving frequency of the first decoration state and the third decoration state corresponding to the maximum attenuation rate, and

[0033] The transverse field driving frequency between the first excited state and the second excited state.

[0034] A quantum bit rapid initialization system, used to perform any of the rapid initialization methods described above, comprising:

[0035] A waveform generator module, wherein the waveform generator module is capable of applying a driving signal or a transverse field drive through a plurality of XY channels respectively;

[0036] A combiner module, the combiner module is used to combine the drive signals or transverse field drives applied by multiple XY channels into a single channel;

[0037] A quantum carrier module, wherein the quantum carrier module is connected to the combiner module and the waveform generator module respectively, and the combiner module applies the transverse field driving signal to the quantum carrier module through an XY channel;

[0038] A reading and display module is connected to the quantum carrier module.

[0039] Optionally, the combiner module and the waveform generator module are both connected to the quantum carrier module via an attenuator and a filter.

[0040] A superconducting quantum computer with rapid quantum bit initialization comprises any of the rapid initialization systems described above and executes any of the rapid initialization methods described above.

[0041] The present invention has the following beneficial effects:

[0042] 1. The present invention calibrates the transverse field driving frequency of the decorated state and the excited state by first calibrating the frequency and Rabi oscillation to obtain the corresponding relationship between the transverse field driving frequency and the transverse field driving amplitude, and then determines the transverse field driving parameter with the fastest initialization rate according to the quantum state evolution probability. After entering the transverse field driving parameter, the equivalent coupling strength between the quantum bit and the resonant cavity can be quickly changed, and a fast dissipation channel is constructed by utilizing the extremely strong photon dissipation rate of the resonant cavity, thereby realizing the fast initialization of the Fluxonium quantum bit.

[0043] 2. Compared with the existing methods of using the bit's own energy relaxation to decay to the ground state, introducing dissipative elements during chip design and processing, and adjusting external magnetic flux signals, the present disclosure greatly shortens the initialization time and greatly improves the experimental efficiency. At the same time, no dissipative elements are introduced in chip design, which reduces the burden on the process. In addition, no magnetic flux signal is introduced, which avoids the magnetic flux disturbance of other bits by low-frequency noise, improves the accuracy of the experiment, and saves energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a flowchart of the fast initialization method;

[0045] Figure 2 is a flow chart of transverse field drive calibration of the third dressing state and the first dressing state;

[0046] Figure 3 The waveform diagram of each channel is a calibration diagram of the transverse field driving frequency between the third dressing state and the first dressing state in a single period;

[0047] Figure 4The first excited state and the second excited state transverse field drive calibration flow chart;

[0048] Figure 5 The waveform diagram of each channel is calibrated for the transverse field driving frequency of the first excited state and the second excited state of a single periodic state;

[0049] Figure 6 Determine the flow chart for the transverse field drive amplitude;

[0050] Figure 7 To quickly initialize the system architecture diagram.

[0051] Legend:

[0052] 1. Waveform generator module; 2. Combiner module; 3. Quantum carrier module; 4. Reading and display module; 5. Attenuator; 6. Filter. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] Please refer to Figure 1 , an embodiment provided by the present disclosure: a method for rapid initialization of quantum bits, specifically a method for rapid initialization of Fluxonium quantum bits. First, an explanation is given for Fluxonium, which is a quantum bit design based on a superconducting quantum circuit, consisting of a superconducting loop composed of a Josephson junction, a coupling capacitor, a microwave control line, a magnetic flux line, and a resonant cavity, and has the characteristics of strong nonlinearity, adjustability, and low-frequency quantum oscillation. Its energy level structure presents a very strong nonlinear characteristic, which makes it highly sensitive to external noise, so its decoherence time is relatively long, which can reach the millisecond level. At the same time, it is precisely because of the long decoherence time that when the Fluxonium quantum bit is initialized, if the quantum bit is allowed to decay to the ground state by itself, it takes a long time. If some dissipative elements are added during the design and processing of the quantum chip, but for the superconducting loop process of the Fluxonium quantum bit, adding dissipative elements will bring a burden and affect the performance of the quantum bit. Finally, if magnetic flux is passed, additional magnetic flux noise may be brought, affecting the error of the quantum bit during the initialization process.

[0055] Therefore, in order to minimize or circumvent the above problems, the present disclosure provides a method for quickly initializing quantum bits that is applicable to quantum bits with a long energy relaxation time such as Fluxonium, and does not introduce additional processes at the chip design and processing level, and does not apply low-frequency signals to cause magnetic flux disturbances;

[0056] Specific methods include:

[0057] S100, calibrate the quantum bit reading cavity frequency, the frequency of the excited state, the Rabi oscillation between the ground state and the excited state, and the Rabi oscillation between the excited states. Optionally, the frequency of the quantum bit reading cavity is calibrated by a vector network analyzer, a microwave source, an arbitrary waveform generator, and other devices. In the Fluxonium quantum bit, there is a coupling capacitor between the reading resonant cavity and the quantum bit, and the quantum bit state is measured by reading the frequency change of the resonant cavity. At the same time, the frequency of the first excited state and the second excited state of the quantum bit, the Rabi oscillation between the ground state and the first excited state, and the Rabi oscillation between the first excited state and the second excited state are calibrated by the above-mentioned device. Among them, the ground state, the first excited state and the second excited state of the Fluxonium quantum bit are regarded as |g>, |e>, |f>, the photon number Fock state in the resonant cavity is read as |0>, |1>, |2>, and the ground state or excited state and the photon number Fock state are coupled with large detuning to form a decorated state as |g1>, |e0>, |f0>. Specifically, in order to make it easier to understand the content of the invention of this application, |g1>, |e0> and |f0> are defined as the first decorated state, the second decorated state and the third decorated state, respectively. It should be noted that the main function of the Rabi oscillation is to determine the energy of the quantum bit from the |g> state to the |e> state and the energy of the quantum bit from the |e> state to the |f> state. To explain the dressed state, when a quantum system interacts with an external field, the system's Hamiltonian contains the original system Hamiltonian and the interaction term. The eigenstate of this total Hamiltonian is the dressed state. That is, the dressed state is a new eigenstate formed by the system and its external environment.

[0058] S200, calibrating the transverse field driving frequency of the decorated state and the transverse field driving frequency of the excited state to obtain a corresponding relationship between the transverse field driving frequency and the transverse field driving amplitude. The specific calibration steps include:

[0059] S210, completing the transverse field driving frequency calibration between the first decoration state |g1> and the third decoration state |f0>;

[0060] The S210 includes:

[0061] S211 first prepares the Fluxonium quantum bit to the first decorated state |g1>;

[0062] S212, based on the first decorated state |g1>, fix the transverse field driving time, and apply transverse driving fields of different frequencies and amplitudes to the XY channel through an arbitrary waveform generator and a combiner, wherein the XY channel is a type of quantum operation acting on a quantum bit, which can perform specific rotations and transformations on the state of the quantum bit. The XY channel can realize rotations of different angles on the Bloch sphere of the quantum bit, thereby changing the state of the quantum bit. The XY channel can be realized by physical means. In some embodiments, the XY channel operation can be realized by controlling the microwave pulses of the superconducting quantum bit. In some other embodiments, the XY channel can be realized by a series of quantum logic gates, that is, a combination of basic quantum logic gates such as Hadamard gates, phase gates, and CNOT gates can be used to realize the XY channel operation;

[0063] S213, scanning and acquiring the energy spectrum of the quantum state of Fluxonium as it changes with the frequency and the amplitude of the driving pulse;

[0064] S214: Fitting the first spectrum line with the highest probability that the quantum bit is in the ground state, to obtain the transverse field driving frequency of the first decoration state |g1> and the third decoration state |f0> and the transverse field driving amplitude corresponding to the transverse field driving frequency. The first spectrum line is the correspondence between the transverse field driving frequency that can quickly reset the Fluxonium quantum bit from the first excited state |e> to the ground state |g> and the transverse field driving amplitude of the third decoration state |f0> and the first decoration state |g1>. Figure 2 As shown. For the transverse field drive between the third embellishment state |f0> and the first embellishment state |g1> with different sets of frequencies and amplitudes, the waveforms of each channel in a single cycle are shown as follows Figure 3 The channels include XY1 channel, XY3 channel and Readin channel.

[0065] S220, complete the calibration of the transverse field driving frequency between the first excited state |e> and the second excited state |f> of the quantum bit. Specifically, because the transition frequency of the Fluxonium quantum bit will also change under different transverse field driving amplitudes of the third decorated state |f0> and the first decorated state |g1>, the transverse field driving frequency between the first excited state |e> and the second excited state |f> will also change with the transverse field driving amplitudes of the third decorated state |f0> and the first decorated state |g1>. Therefore, it is necessary to rescan the energy spectrum to complete the calibration of the transverse field driving frequency between the first excited state |e> and the second excited state |f>. Please refer to Figure 4 , the specific calibration steps include:

[0066] S221, in addition to applying a normal driving signal on the XY channel through an arbitrary waveform generator, an additional pulse signal is applied to excite the quantum bit from the first excited state |e> to the second excited state |f>. The length and amplitude of the applied pulse signal can be determined by the Rabi oscillation experiment between the first excited state |e> and the second excited state |f> of the Fluxonium quantum bit. For the waveform diagram of each channel in a single cycle, please refer to Figure 5 , I won’t go into too much detail here;

[0067] S222, applying the transverse field driving frequency and transverse field driving amplitude of the first decorated state |g1> and the third decorated state |f0> fitted in step S214 to the XY channel of the Fluxonium quantum bit;

[0068] S223, scanning and obtaining the transverse field driving frequency between the first excited state |e> and the second excited state |f> of the Fluxonium quantum bits in different groups, and

[0069] Energy spectra of different groups of first-dressed states |g1> and third-dressed states |f0> under transverse field driving amplitudes;

[0070] S224, fitting the second spectrum line with the highest probability that the quantum bit is in the ground state, so as to obtain the transverse field driving frequency between the first excited state |e> and the second excited state |f> and the corresponding transverse field driving amplitude of the first decorated state |g1> and the third decorated state |f0>. Among them, the second spectrum line is the correspondence between the transverse field driving frequency of the first excited state |e> and the second excited state |f> and the transverse field driving amplitude of the first decorated state |g1> and the third decorated state |f0>, which can quickly initialize the Fluxonium quantum bit from the first excited state |e>.

[0071] S300, measuring the probability of quantum state ground state evolution under different transverse field driving amplitudes, and determining the transverse field driving parameter with the fastest initialization rate in combination with the corresponding relationship between the transverse field driving frequency and the transverse field driving amplitude in S200;

[0072] The specific steps include:

[0073] After determining the corresponding relationship between the transverse field driving frequency and the transverse field driving amplitudes of the third dressing state |f0> and the first dressing state |g1>, the transverse field driving amplitude with the fastest initialization rate is determined.

[0074] S310, obtaining the transverse field driving frequencies of the first decoration state |g1> and the third decoration state |f0> and the transverse field driving frequencies between the first excited state |e> and the second excited state |f> corresponding to the transverse field driving amplitudes of the first decoration state |g1> and the third decoration state |f0> of different groups;

[0075] S320, measuring the quantum state ground state evolution probability for different groups of transverse field driving frequencies and amplitudes;

[0076] S321, construct the quantum system state evolution equation and cyclically solve the coupling parameters and decay rate. Specifically, the probability of the quantum system evolving from the initial state |s0> to the state |s> over time can be calculated by the quantum system state evolution equation:

[0077]

[0078]

[0079] In the above formula, H is the Hamiltonian of the quantum system, λ k is the coupling parameter;

[0080] P(s0→s,t): the probability that the quantum system evolves from the initial state |s0> to the target state |s> after time t;

[0081] K, j, m: different states of the quantum system;

[0082] T jk , The coupling strength or transition probability (evolution matrix) between quantum states j, k (or k, m), where is the complex conjugate form of the evolution matrix;

[0083] <s|e -iHt |s0>: the amplitude of the initial state |s0> evolving to the state |s> after time t under the control of Hamiltonian H;

[0084] <s(t0)|s> : The inner product between the quantum states s(t0) and |s>;

[0085] By using the above formula, we can solve λ k , the imaginary part of the coupling parameter determines the decay rate of the Fluxonium qubit;

[0086] S322, in the present disclosure, the transverse field driving amplitude and transverse field driving frequency of the first and third decorated states corresponding to the maximum decay rate, and the transverse field driving frequency between the first excited state and the second excited state are obtained. Specifically, the decay rate γ of the Fluxonium quantum bit from the second excited state |f> to the ground state |g> is defined as k =min(|Im(λ k)|), change the amplitude of the transverse field drive of the third decorated state |f0> and the first decorated state |g1> of the Fluxonium quantum bit, apply the transverse field drive frequency corresponding to the amplitude, and then calculate the decay rate. The driving amplitude corresponding to the maximum decay rate is the transverse field drive amplitude with the fastest initialization rate of the Fluxonium quantum bit, and the corresponding driving frequency between the first excited state |e> and the second excited state |f>, and between the third decorated state |f0> and the first decorated state |g1>, is the transverse field drive frequency that can quickly initialize the Fluxonium quantum bit, see Figure 6 .

[0087] S400, applying the transverse field driving parameters obtained in S300 to the corresponding channel to achieve rapid initialization of the quantum bit; specifically, after determining the transverse field driving frequency that can quickly initialize the Fluxonium quantum bit and the transverse field driving amplitude that can initialize the Fluxonium quantum bit at the fastest rate, inject the above transverse field driving frequency and transverse field driving amplitude into the resonant cavity through the XY channel;

[0088] Thereby changing the equivalent coupling strength between the quantum bit and the reading cavity and constructing a fast dissipation channel through the resonant cavity to achieve rapid initialization of the quantum bit. Specifically, there is coupling between the Fluxonium quantum bit and its corresponding reading cavity. When an external microwave field, i.e., a transverse field drive, is coupled and interacts with it, it will promote the occurrence of the Raman process. In this process, the bit can cause the quantum state to change by absorbing or emitting a photon. Therefore, in the present application, the transverse field drive is achieved by applying a microwave field of a specific frequency and amplitude, thereby changing the coupling between the bit and the reading cavity, causing the energy level structure between the bit and the reading cavity to change, and utilizing the extremely strong photon dissipation rate of the resonant cavity to construct an energy dissipation channel of the system, thereby achieving rapid initialization of the Fluxonium quantum bit.

[0089] Please refer to Figure 7 The present disclosure also provides an embodiment: a quantum bit rapid initialization system, which is used to execute the above-mentioned rapid initialization method, specifically comprising:

[0090] The waveform generator module 1 can be an arbitrary waveform generator, which includes at least four channels, including an XY1 channel, an XY2 channel, an XY3 channel and a Readin channel, wherein the XY1 channel is used to apply a drive signal for normal manipulation of the quantum bit, i.e., a driving signal, such as driving the quantum bit to the second excited state |f>, the XY2 channel is used to apply a transverse field drive between the first excited state |e> and the second excited state |f>, and the Readin channel is used to read the quantum state.

[0091] Combiner module 2, which can use a three-in-one combiner, which can apply the transverse field driving frequency and amplitude applied by the XY1 channel, the XY2 channel, and the XY3 channel to the XY channel of the quantum bit, thereby changing the coupling between the quantum bit and the resonant cavity, and changing the energy level structure between the quantum bit and the reading cavity.

[0092] The reading and display module 4 can be optionally a digital acquisition instrument, which is connected to the quantum carrier module 3, i.e., the Fluxonium quantum bit, through a room temperature amplifier, a low temperature amplifier, a three-section isolator, and an infrared filter 6 which are arranged in sequence, and can acquire and display various parameters of the Fluxonium quantum bit.

[0093] It should be noted that the quantum carrier module 3 is a Fluxonium quantum bit, which is composed of a superconducting loop composed of a Josephson junction, a coupling capacitor, a microwave control line, a magnetic flux line and a resonant cavity. The combiner module 2 and the waveform generator module 1 are connected to the quantum carrier module 3 through an attenuator 5 and a filter 6. The attenuator 5 can be used to adjust the signal strength to meet the input requirements of the XY channel. The filter 6 can be used to eliminate noise and interference to select a specific quantum state or frequency range.

[0094] The present invention also discloses an embodiment, a superconducting quantum computer with rapid initialization of quantum bits, comprising any of the rapid initialization systems described above and executing any of the rapid initialization methods described above.

[0095] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for rapid initialization of quantum bits, characterized in that: include: S100, calibrating the quantum bit reading cavity frequency, the frequency of the excited state, the Rabi oscillation between the ground state and the first excited state, and the Rabi oscillation between the excited states; S200, calibrating the transverse field driving frequency of the decorated state and the transverse field driving frequency of the excited state to obtain a corresponding relationship between the transverse field driving frequency and the transverse field driving amplitude; S300, measuring the probability of quantum state ground state evolution under different transverse field driving amplitudes, and determining the transverse field driving parameter with the fastest initialization rate in combination with the corresponding relationship between the transverse field driving frequency and the transverse field driving amplitude in S200; S400, applying the transverse field driving parameters obtained in S300 to the corresponding channel to achieve rapid initialization of the quantum bit.

2. The method for rapid initialization of quantum bits according to claim 1, characterized in that: In step S100, the calibration device calibrates the reading cavity frequency of the quantum bit, calibrates the frequencies of the first excited state and the second excited state of the quantum bit, calibrates the Rabi oscillation between the ground state and the first excited state of the quantum bit, and calibrates the Rabi oscillation between the first excited state and the second excited state of the quantum bit.

3. The method for rapid initialization of quantum bits according to claim 1, characterized in that: The step S200 includes: S210, completing the transverse field driving frequency calibration of the first decoration state and the third decoration state; S220, completing the transverse field driving frequency calibration of the first excited state and the second excited state of the quantum bit.

4. The method for rapid initialization of quantum bits according to claim 3, characterized in that: Step S210 includes: S211, preparing the quantum bit to a first dressed state; S212, based on the first decoration state, fixing the transverse field driving time, and applying transverse driving fields of different frequencies and amplitudes on the XY channel; S213, obtaining an energy spectrum of the quantum state as it changes with frequency and driving amplitude ratio; S214, fitting a first spectrum line with the highest probability that the quantum bit is in the ground state, to obtain the transverse field driving frequencies of the third decorated state and the first decorated state and the transverse field driving amplitudes corresponding to the transverse field driving frequencies.

5. The method for rapid initialization of quantum bits according to claim 1, characterized in that: Step S220 includes: S221, exciting the quantum bit from a first excited state to a second excited state; S222, applying the transverse field driving frequency and transverse field driving amplitude of the first and third dressed states fitted in step S214 to the XY channel of the quantum bit; S223, obtaining the transverse field driving frequency of the quantum bit between the first excited state and the second excited state of different groups, and Energy spectra of different groups of first and third dressed states under transverse field driving amplitudes; S224, fitting the second spectrum line with the highest probability of the quantum bit being in the ground state to obtain the transverse field driving frequency between the first excited state and the second excited state and the corresponding transverse field driving amplitudes of the first decorated state and the third decorated state.

6. The method for rapid initialization of quantum bits according to claim 1, characterized in that: Step S300 includes: S310, obtaining the transverse field driving frequencies of the first dressing state and the third dressing state and the transverse field driving frequencies between the first excited state and the second excited state corresponding to the transverse field driving amplitudes of the first dressing state and the third dressing state of different groups; S320, measuring the quantum state ground state evolution probability for different groups of transverse field driving frequencies and amplitudes; S321, construct the quantum system state evolution equation and cyclically solve the coupling parameters and decay rate; S322, obtaining the transverse field driving amplitude and transverse field driving frequency of the first decoration state and the third decoration state corresponding to the maximum attenuation rate, and The transverse field driving frequency between the first excited state and the second excited state.

7. A quantum bit rapid initialization system, used to execute the rapid initialization method of any one of claims 1 to 6, characterized in that: include: A waveform generator module, wherein the waveform generator module is capable of applying a driving signal or a transverse field drive through a plurality of XY channels respectively; A combiner module, the combiner module is used to combine the drive signals or transverse field drives applied by multiple XY channels into a single channel; A quantum carrier module, wherein the quantum carrier module is connected to the combiner module and the waveform generator module respectively, and the combiner module applies the transverse field driving signal to the quantum carrier module through an XY channel; A reading and display module is connected to the quantum carrier module.

8. The quantum bit rapid initialization system according to claim 7, characterized in that: The combiner module and the waveform generator module are both connected to the quantum carrier module through an attenuator and a filter.

9. A superconducting quantum computer with fast quantum bit initialization, characterized in that: The fast initialization system comprises any one of claims 7-8 and executes the fast initialization method of any one of claims 1-6.

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