Quantum circuit optimization method and system based on CCZS gate

Abstract

The invention relates to the technical field of quantum computing, in particular to a quantum circuit optimization method and system based on a CCZS gate, the CCZS gate is utilized to construct a quantum circuit key quantum gate, and the key quantum gate comprises a quantum fan-out gate, a quantum parity check gate, a control phase gate and a local fully-connected CZ gate. The CCZS gate is a three-quantum-bit gate comprising a control bit and two target bits, and the state of the target bits is changed by using the state of the control bit; and optimizing the target quantum algorithm quantum circuit based on the key quantum gate constructed by the CCZS gate, so as to optimize the fidelity and execution time of the target quantum algorithm quantum circuit by adjusting the line depth and / or gate number of the target quantum algorithm quantum circuit. The depth of a quantum circuit can be reduced, the fidelity of a quantum algorithm is improved, the execution efficiency of complex quantum algorithms such as a quantum Fourier transform algorithm and a quantum approximate optimization algorithm is improved, and the requirement of the algorithm for quantum hardware resources is reduced.

Description

Technical Field

[0001] The present invention relates to the field of quantum computing technology, and in particular to a quantum circuit optimization method and system based on CCZS gates. Background Art

[0002] With the rapid development of quantum computing technology, quantum computers have shown great potential in many fields. However, limited by quantum bit decoherence and quantum gate errors, current and near-term superconducting quantum computers can only run low-depth quantum circuits to achieve acceptable fidelity. Traditional quantum computing usually relies on single-qubit and two-qubit gates as universal gate sets, which leads to a significant increase in the depth of quantum circuits for complex quantum algorithms or the decomposition of multi-qubit entanglement.

[0003] In recent years, the generation of efficient multi-qubit gates by simultaneously applying two-qubit gates has become a research hotspot. In particular, the Controlled-CPHASE-SWAP (CCZS) gate has shown great potential in quantum circuit synthesis because it is faster than the Controlled-Z (CZ) gate alone and can be implemented at the coherence limit. However, how to effectively apply the CCZS gate to quantum circuit synthesis to improve the execution efficiency and fidelity of quantum algorithms remains an urgent problem to be solved. Summary of the invention

[0004] To this end, the present invention provides a quantum circuit optimization method and system based on CCZS gate to solve the problem of unsatisfactory algorithm execution efficiency and fidelity of the existing CCZS gate in the comprehensive application of quantum circuits.

[0005] According to the design scheme provided by the present invention, on the one hand, a quantum circuit optimization method based on CCZS gate is provided, comprising:

[0006] The key quantum gates of the quantum circuit are constructed using CCZS gates. The CCZS gate is a three-qubit gate including a control bit and two target bits, and the target bit state is changed using the control bit state. The key quantum gates include a quantum fan-out gate, a quantum parity check gate, and a control phase gate.

[0007] The target quantum algorithm quantum circuit is optimized based on the key quantum gates constructed based on the CCZS gates, so as to optimize the fidelity and running time of the target quantum algorithm quantum circuit by adjusting the line depth and / or the number of gates of the target quantum algorithm quantum circuit.

[0008] As a quantum circuit optimization method based on CCZS gates of the present invention, further, a quantum fan-out gate is constructed using CCZS gates, including:

[0009] Set the corresponding data qubits and auxiliary qubits according to the number of qubits of the quantum fan-out gate, and set the auxiliary qubits to the |1> state;

[0010] An H gate is set on the quantum circuit of the remaining quantum bits except the first data quantum bit, the auxiliary quantum bit is used as the control bit of the CCZS gate, and the two target bits of the CCZS gate are used to execute the SWAP gate and the CZ gate, and an H gate is set on the quantum circuit of the remaining quantum bits except the last data quantum bit.

[0011] As a quantum circuit optimization method based on CCZS gate of the present invention, further, a quantum parity check gate is constructed by using CCZS gate, comprising:

[0012] Add an H gate before and after the control NOT gate of the quantum parity check gate to adjust the control-target relationship of the control NOT gate and make the quantum parity check gate equivalent to a quantum fan-out gate;

[0013] The CCZS gate is used to construct a quantum fan-out gate equivalent to a quantum parity gate.

[0014] As a quantum circuit optimization method based on CCZS gate of the present invention, further, a controlled phase gate is constructed by using CCZS gate, comprising:

[0015] Two CCZS gates and an intermediate single-qubit rotation gate are set to decompose the control phase gate into two CCZS gates and a single-qubit rotation gate;

[0016] Auxiliary qubits, control qubits and target qubit circuits are set according to CCZS gates and single-qubit rotation gates, so that the states of the control qubits and target qubits are controlled by CCZS gates in the quantum circuit and the phase of the auxiliary qubits is rotated by single-qubit rotation gates.

[0017] On the other hand, the present invention also provides a quantum circuit optimization system based on CCZS gate, comprising: a gate circuit equivalent module and a quantum circuit optimization module, wherein:

[0018] A gate circuit equivalent module is used to construct a key quantum gate of a quantum circuit using a CCZS gate. The CCZS gate is a three-qubit gate including a control bit and two target bits, and the control bit state is used to change the target bit state. The key quantum gate includes a quantum fan-out gate, a quantum parity check gate, and a control phase gate.

[0019] The quantum circuit optimization module is used to optimize the target quantum algorithm quantum circuit based on the key quantum gates constructed by CCZS gates, so as to optimize the fidelity and running time of the target quantum algorithm quantum circuit by adjusting the circuit depth and / or the number of gates of the target quantum algorithm quantum circuit.

[0020] In another aspect, the present invention further provides a method for implementing a quantum Fourier transform algorithm based on quantum circuit optimization, which is implemented based on the above-mentioned quantum circuit optimization method, and the implementation process includes:

[0021] Use CCZS gate to construct the controlled phase gate in quantum Fourier transform quantum circuit;

[0022] A controlled phase gate constructed by using a CCZS gate replaces a controlled phase gate in a quantum Fourier change quantum circuit, and a quantum Fourier transform equivalent quantum circuit is obtained, so as to realize quantum Fourier transform using the equivalent quantum circuit.

[0023] As a quantum Fourier transform algorithm implementation method based on quantum circuit optimization of the present invention, further, a CCZS gate is used to construct a control phase gate in a quantum Fourier transform quantum circuit, comprising:

[0024] Configure the quantum processor according to the quantum Fourier transform algorithm, and lock the auxiliary quantum bits in the quantum processor in the |0> state;

[0025] A controlled phase gate equivalent to a controlled phase gate is constructed using two CCZS gates and an intermediate single-qubit rotation gate, so that the states of the control qubit and the target qubit can be controlled through the CCZS gate in the quantum circuit and the phase of the auxiliary qubit can be rotated through the single-qubit rotation gate.

[0026] In another aspect, the present invention further provides a method for implementing a quantum approximate optimization algorithm based on quantum circuit optimization, which is implemented based on the above-mentioned quantum circuit optimization method, and the implementation process includes:

[0027] Get the controlled NOT gate in the quantum approximation optimized quantum circuit and convert the controlled NOT gate into a CZ gate and a single-bit gate;

[0028] The quantum processor is configured according to the quantum approximate optimization algorithm, and the auxiliary quantum bits in the quantum processor are placed in the |1> quantum state, so as to use the auxiliary quantum bits as control quantum bits to activate the CZ gate between the target quantum bit pairs;

[0029] The CCZS gate is used to construct the equivalent gate structure circuit of the CZ gate in the quantum approximate optimization quantum circuit, and the CZ gate equivalent gate structure circuit is used to realize the local fully connected CZ gate between the target quantum bits.

[0030] Beneficial effects of the present invention:

[0031] The present invention uses CCZS gates to construct efficient equivalent quantum gates to optimize quantum algorithms, significantly reduce the depth of quantum circuits, and improve the fidelity of quantum algorithms. In complex quantum algorithms such as quantum Fourier transform and quantum approximate optimization algorithms, it can improve the execution efficiency of the algorithms, reduce the algorithm's demand for quantum hardware resources, and improve the computing efficiency of quantum computing devices. It has good application prospects in the field of quantum computing. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The initial mapping of the 5-qubit quantum fan-out gate in the embodiment and the circuit diagram under CCZS gate implementation;

[0033] Figure 2 This is a schematic diagram of the process of constructing a control phase gate based on a CCZS gate in an embodiment;

[0034] Figure 3 Schematic diagram of coupling of a 5-qubit quantum processor in an embodiment;

[0035] Figure 4 This is a schematic diagram of the quantum Fourier circuit structure of 4 quantum bits in the embodiment;

[0036] Figure 5 Schematic diagram of an equivalent gate structure constructed by a local fully connected CZ gate in a network topology structure in the embodiment. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the present invention clearer and more understandable, the present invention is further described in detail below in conjunction with the accompanying drawings and technical solutions.

[0038] An embodiment of the present invention provides a quantum circuit optimization method based on CCZS gate, comprising:

[0039] The key quantum gates of the quantum circuit are constructed using CCZS gates. The CCZS gate is a three-qubit gate including a control bit and two target bits, and the target bit state is changed using the control bit state. The key quantum gates include a quantum fan-out gate, a quantum parity check gate, and a control phase gate.

[0040] The target quantum algorithm quantum circuit is optimized based on the key quantum gates constructed based on the CCZS gates, so as to optimize the fidelity and running time of the target quantum algorithm quantum circuit by adjusting the line depth and / or the number of gates of the target quantum algorithm quantum circuit.

[0041] The Controlled-CPHASE-SWAP (CCZS) gate is a three-qubit gate commonly used in quantum computing. It combines the functions of the Controlled-PHASE (CPHASE) and SWAP gates to implement complex operations on three qubits. That is, the CCZS gate is a three-qubit gate containing one control bit and two target bits, and uses the control bit state to change the target bit state. When using the CCZS gate to construct an equivalent gate structure circuit, appropriate CCZS gate parameters such as SWAP angle θ, SWAP phase φ, and CPHASE phase γ can be selected according to the specific needs of the quantum circuit to achieve the required quantum logic operations. According to the requirements of the quantum algorithm, a quantum circuit structure containing the CCZS gate is designed, and the key steps in the quantum algorithm are implemented by reasonably arranging the position and order of the CCZS gate. By adjusting the parameters and circuit structure of the CCZS gate, the depth of the quantum circuit can be reduced, the fidelity and execution time of the quantum circuit can be optimized, and the performance requirements of the quantum algorithm can be met.

[0042] As a highly entangled three-qubit gate, the CCZS gate can be operated by applying two CZ gates simultaneously on three qubits with nearest neighbor coupling. In this embodiment, the parameters of the CCZS gate can be set to θ = π / 2, φ = 0, and γ = 0. These parameters are selected based on previous research and experimental verification to ensure the efficiency and robustness of the CCZS gate in quantum circuit synthesis.

[0043] Among them, the quantum fan-out gate constructed by using CCZS gate can be designed to include:

[0044] Set the corresponding data qubits and auxiliary qubits according to the number of qubits of the quantum fan-out gate, and set the auxiliary qubits to the |1> state;

[0045] An H gate is set on the quantum circuit of the remaining quantum bits except the first data quantum bit, the auxiliary quantum bit is used as the control bit of the CCZS gate, and the two target bits of the CCZS gate are used to execute the SWAP gate and the CZ gate, and an H gate is set on the quantum circuit of the remaining quantum bits except the last data quantum bit.

[0046] In quantum computing, a quantum fan-out gate is a basic and important logic gate that can copy the state of a quantum bit to multiple target quantum bits. Traditional quantum fan-out gate implementations usually require more quantum gates and longer circuit depths, resulting in limited implementation efficiency and fidelity. In this embodiment, constructing a quantum fan-out gate based on the CCZS gate can reduce the number of required quantum gates and circuit depth, and improve the fidelity and efficiency of the fan-out gate.

[0047] like Figure 1As shown in the figure, taking the construction of a 5-qubit quantum fan-out gate as an example, first prepare 5 data qubits (Q1, Q2, Q3, Q4, Q5) and 4 auxiliary qubits (A1, A2, A3, A4) set to the |1> state. Set each auxiliary qubit as the control qubit of CCZS, and use the CCZS gate to perform simultaneous SWAP and CZ operations between data qubits. By activating different auxiliary qubits one by one to execute CCZS gates, the CZ gate on the data bit can be gradually implemented. In this process, since the CCZS gate has its own SWAP operation, it is necessary to apply the Hadamard gate to the data qubit (except the Q1 qubit) to correct the phase at the end. In this way, an efficient quantum fan-out gate is constructed with fewer quantum gates and a shallower circuit depth.

[0048] Among them, the quantum parity check gate constructed by using CCZS gate can be designed to include:

[0049] Add an H gate before and after the control NOT gate of the quantum parity check gate to adjust the control-target relationship of the control NOT gate and make the quantum parity check gate equivalent to a quantum fan-out gate;

[0050] A quantum fan-out gate equivalent to a quantum parity check gate is constructed using the CCZS gate.

[0051] The quantum parity gate is a logic gate used to check the overall state of multiple quantum bits (odd number of 1s or even number of 1s). It has important applications in quantum error correction and quantum algorithms. In the embodiment of this case, when constructing a quantum parity gate based on the CCZS gate, an H gate is added before and after the control quantum bit and target quantum bit of each CNOT gate in the parity gate to achieve the inversion of the control-target relationship, thereby obtaining a circuit equivalent to a quantum fan-out gate. In this way, the quantum fan-out gate is first constructed with the CCZS gate, and then the parity gate is constructed. By cleverly utilizing the characteristics of the CCZS gate, efficient quantum parity can be achieved without adding additional SWAP gates.

[0052] Among them, using CCZS gate to build a control phase gate can include:

[0053] Two CCZS gates and an intermediate single-qubit rotation gate are set to decompose the control phase gate into two CCZS gates and a single-qubit rotation gate;

[0054] Auxiliary qubits, control qubits and target qubit circuits are set according to CCZS gates and single-qubit rotation gates, so that the states of the control qubits and target qubits are controlled by CCZS gates in the quantum circuit and the phase of the auxiliary qubits is rotated by single-qubit rotation gates.

[0055] Traditional control R n The gate decomposition method usually requires multiple CNOT gates and single-qubit rotation gates, which increases the circuit depth and complexity. However, in the embodiment of this case, this goal can be achieved more concisely through the CCZS gate.

[0056] Specifically, if Figure 2 As shown, (a) is the control R n Gate, (b) is to control R n The gate decomposition consists of two Controlled-SWAP gates (using two CCZS gate operations to eliminate unnecessary CCZ effects and retain only the required Controlled-SWAP operations) and an intermediate single-qubit rotation gate. The specific implementation can be summarized as follows:

[0057] Initialization: put the auxiliary qubit in state |0>, and the control qubit and one target qubit in arbitrary states.

[0058] The first CCZS gate operation: Use the CCZS gate to operate the control qubit and the two target qubits. This step will implement both Controlled-SWAP and CCZ operations, but the CCZ effect can be eliminated through subsequent operations.

[0059] Intermediate rotation: Apply a single-qubit rotation gate Rn on the auxiliary qubit to achieve the required phase rotation.

[0060] Second CCZS gate operation: CCZS gates are used again to operate the control qubit and the target qubit. This step will implement the Controlled-SWAP and CCZ operations again, but after combining with the first operation, the CCZ effects cancel each other out, leaving only the desired control phase effect.

[0061] Through the above steps, the controlled Rn gate can be realized using only three gates (two CCZS gates and one single-qubit rotation gate), which greatly reduces the number of quantum gates required and the circuit depth.

[0062] Furthermore, based on the above method, an embodiment of the present invention also provides a quantum circuit optimization system based on CCZS gates, comprising: a gate circuit equivalent module and a quantum circuit optimization module, wherein:

[0063] A gate circuit equivalent module is used to construct a key quantum gate of a quantum circuit using a CCZS gate. The CCZS gate is a three-qubit gate including a control bit and two target bits, and the control bit state is used to change the target bit state. The key quantum gate includes a quantum fan-out gate, a quantum parity check gate, and a control phase gate.

[0064] The quantum circuit optimization module is used to optimize the target quantum algorithm quantum circuit based on the key quantum gates constructed by CCZS gates, so as to optimize the fidelity and running time of the target quantum algorithm quantum circuit by adjusting the circuit depth and / or the number of gates of the target quantum algorithm quantum circuit.

[0065] Quantum Fourier transform (QFT) is a basic and widely used algorithm in quantum computing, especially in quantum chemistry, quantum simulation and other fields. However, traditional QFT implementation usually requires a large number of basic quantum gates (such as CZ gates, H gates, etc.), which will significantly increase the circuit depth and complexity.

[0066] Furthermore, based on the above-mentioned quantum circuit optimization method, an embodiment of the present invention also provides a method for implementing a quantum Fourier transform algorithm based on quantum circuit optimization, comprising:

[0067] Use CCZS gate to construct the controlled phase gate in quantum Fourier transform quantum circuit;

[0068] A controlled phase gate constructed by using a CCZS gate replaces a controlled phase gate in a quantum Fourier change quantum circuit, and a quantum Fourier transform equivalent quantum circuit is obtained, so as to realize quantum Fourier transform using the equivalent quantum circuit.

[0069] Among them, the quantum processor is configured according to the quantum Fourier transform algorithm, and the auxiliary quantum bit in the quantum processor is locked in the |0> state; two CCZS gates and an intermediate single-qubit rotation gate are used to construct a controlled phase gate equivalent to the controlled phase gate, so that the control quantum bit and the target quantum bit state can be controlled through the CCZS gate in the quantum circuit, and the auxiliary quantum bit can be phase rotated through the single-qubit rotation gate.

[0070] Specifically, to perform the quantum Fourier transform (QFT) algorithm using the CCZS gate, the following can be used: Figure 3 The hardware coupling scheme shown in Figure 1, where A is regarded as an auxiliary qubit locked in the |0> state. Under this coupling structure, a CCZS gate can be implemented between Q1, Q2 (or Q3, Q4) and A, where Q1 is the control qubit and Q2 (or Q3, Q4) and A are the target qubits. This means that a controlled R n The gate method realizes controlled R between Q1 and Q2 (or Q3, Q4) n However, in the QFT algorithm, most of the controlled R n The gates have the same target qubit but different control qubits, e.g. Figure 4 In order to better utilize this structure to execute the QFT algorithm, it is necessary to adjust the control-target relationship of the controlled Rn gate in the QFT algorithm.n Swapping the roles of the control qubit and the target qubit in the gate does not change its matrix. Therefore, we can get Figure 4 The equivalent quantum bit QFT circuit shown in (b) in the figure can be used to better construct the QFT algorithm quantum circuit using CCZS gates.

[0071] On the other hand, in order to effectively utilize the CCZS gate in the quantum approximate optimization algorithm (QAOA), an embodiment of the present invention further provides a quantum approximate optimization algorithm implementation method based on quantum circuit optimization. Based on the above-mentioned quantum circuit optimization method, the implementation process includes:

[0072] Get the controlled NOT gate in the quantum approximation optimized quantum circuit and convert the controlled NOT gate into a CZ gate and a single-bit gate;

[0073] The quantum processor is configured according to the quantum approximate optimization algorithm, and the auxiliary quantum bits in the quantum processor are placed in the |1> quantum state, so as to use the auxiliary quantum bits as control quantum bits to activate the CZ gate between the target quantum bit pairs;

[0074] The CCZS gate is used to construct the equivalent gate structure circuit of the CZ gate in the quantum approximate optimization quantum circuit, and the CZ gate equivalent gate structure circuit is used to realize the local fully connected CZ gate between the target quantum bits.

[0075] Constructing a local fully connected CZ gate on a quantum processor is a key step in implementing the QAOA algorithm. In this embodiment, consider a quantum bit layout such as Figure 5 As shown, it contains a qubit A (auxiliary qubit) located in the center and four qubits Q1, Q2, Q3, Q4 surrounding it. This layout allows the realization of a locally fully connected CZ gate structure. The auxiliary qubit A is placed in the quantum state |1> to ensure that in the subsequent CCZS gate operation, A can be used as a control qubit to activate the CZ operation between the target qubit pair. At the same time, Q1, Q2, Q3, Q4 are initialized to the required initial state. For any two qubits Q in Q1, Q2, Q3, Q4 i and Q j (i,j=1,2,3,4 and i≠j), a CCZS gate operation can be performed, where A is the control qubit and Q i and Q j As the target qubit, the CCZS gate will simultaneously realize Q i and Q j However, in the construction of the local fully connected CZ gate, the main focus is on the CZ operation, and the SWAP operation can be performed by reordering (i.e., remapping) the qubits after the entire quantum circuit is executed to restore the original layout or meet other algorithmic requirements.

[0076] Through the above steps, the CCZS gate can be used to realize a local fully connected CZ gate structure between quantum bits Q1, Q2, Q3, and Q4. This method avoids the use of a large number of SWAP gates when constructing CZ gates, thereby reducing the complexity and running time of the circuit, while improving the fidelity of the circuit.

[0077] After constructing a local fully connected CZ gate network, these CZ gates and single-qubit gates can be used to implement the QAOA algorithm. The details are as follows:

[0078] The QAOA algorithm constructs quantum circuits by alternately applying parameterized quantum gates (usually CNOT gates and single-qubit rotation gates). First, the CNOT gates can be converted into CZ gates and single-qubit gates. Consider Figure 4 In the topology shown, for each layer of QAOA, a series of single-qubit rotation gates are applied, and for CZ gates, CZ gates constructed by CCZS gates are applied to realize the interaction between qubits.

[0079] Since the CCZS gate is accompanied by a SWAP operation when constructing the CZ gate, it is necessary to consider the execution position of the single-bit gate when necessary.

[0080] Through the above steps, the CCZS gate can be used to efficiently implement the complex quantum circuit required by the QAOA algorithm on a quantum processor. Compared with the traditional method, this method reduces the number of SWAP gates used, reduces the noise and decoherence effects in the quantum state exchange process, and thus improves the execution efficiency and result accuracy of the QAOA algorithm.

[0081] Unless otherwise specifically stated, the relative steps, numerical expressions and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0082] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0083] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A quantum circuit optimization method based on CCZS gate, characterized in that: Include: The key quantum gates of the quantum circuit are constructed using CCZS gates. The CCZS gate is a three-qubit gate including a control bit and two target bits, and the target bit state is changed using the control bit state. The key quantum gates include a quantum fan-out gate, a quantum parity check gate, and a control phase gate. The target quantum algorithm quantum circuit is optimized based on the key quantum gates constructed based on the CCZS gates, so as to optimize the fidelity and running time of the target quantum algorithm quantum circuit by adjusting the line depth and / or the number of gates of the target quantum algorithm quantum circuit.

2. The CCZS gate-based quantum circuit optimization method according to claim 1, characterized in that: Use CCZS gates to build quantum fan-out gates, including: Set the corresponding data qubits and auxiliary qubits according to the number of qubits of the quantum fan-out gate, and set the auxiliary qubits to the |1> state; An H gate is set on the quantum circuit of the remaining quantum bits except the first data quantum bit, the auxiliary quantum bit is used as the control bit of the CCZS gate, and the two target bits of the CCZS gate are used to execute the SWAP gate and the CZ gate, and an H gate is set on the quantum circuit of the remaining quantum bits except the last data quantum bit.

3. The CCZS gate-based quantum circuit optimization method according to claim 1, characterized in that: Use CCZS gates to construct quantum parity gates, including: Add an H gate before and after the control NOT gate of the quantum parity check gate to adjust the control-target relationship of the control NOT gate and make the quantum parity check gate equivalent to a quantum fan-out gate; A quantum fan-out gate equivalent to a quantum parity gate is constructed using the CCZS gate.

4. The CCZS gate-based quantum circuit optimization method according to claim 1, characterized in that: Use CCZS gate to build a control phase gate, including: Two CCZS gates and an intermediate single-qubit rotation gate are set to decompose the control phase gate into two CCZS gates and a single-qubit rotation gate; Auxiliary qubits, control qubits and target qubit circuits are set according to CCZS gates and single-qubit rotation gates, so that the states of the control qubits and target qubits are controlled by CCZS gates in the quantum circuit and the phase of the auxiliary qubits is rotated by single-qubit rotation gates.

5. A quantum circuit optimization system based on CCZS gate, characterized in that: Contains: gate circuit equivalent module and quantum circuit optimization module, among which, A gate circuit equivalent module is used to construct a key quantum gate of a quantum circuit using a CCZS gate. The CCZS gate is a three-qubit gate including a control bit and two target bits, and the control bit state is used to change the target bit state. The key quantum gate includes a quantum fan-out gate, a quantum parity check gate, and a control phase gate. The quantum circuit optimization module is used to optimize the target quantum algorithm quantum circuit based on the key quantum gates constructed by CCZS gates, so as to optimize the fidelity and running time of the target quantum algorithm quantum circuit by adjusting the circuit depth and / or the number of gates of the target quantum algorithm quantum circuit.

6. A method for implementing a quantum Fourier transform algorithm based on quantum circuit optimization, characterized in that: Based on the quantum circuit optimization method of claim 1, the implementation process includes: Use CCZS gate to construct the controlled phase gate in quantum Fourier transform quantum circuit; The controlled phase gate constructed by CCZS gate replaces the controlled phase gate in the quantum Fourier change quantum circuit, and obtains the quantum Fourier transform equivalent quantum circuit, so as to realize the quantum Fourier transform by using the equivalent quantum circuit.

7. The method for implementing a quantum Fourier transform algorithm based on quantum circuit optimization according to claim 6, characterized in that: The CCZS gate is used to construct the phase control gate in the quantum Fourier transform quantum circuit, including: Configure the quantum processor according to the quantum Fourier transform algorithm, and lock the auxiliary quantum bits in the quantum processor in the |0> state; A controlled phase gate equivalent to a controlled phase gate is constructed using two CCZS gates and an intermediate single-qubit rotation gate, so that the states of the control qubit and the target qubit can be controlled through the CCZS gate in the quantum circuit and the phase of the auxiliary qubit can be rotated through the single-qubit rotation gate.

8. A method for implementing a quantum approximate optimization algorithm based on quantum circuit optimization, characterized in that: Based on the quantum circuit optimization method of claim 1, the implementation process includes: Get the controlled NOT gate in the quantum approximation optimized quantum circuit and convert the controlled NOT gate into a CZ gate and a single-bit gate; The quantum processor is configured according to the quantum approximate optimization algorithm, and the auxiliary quantum bits in the quantum processor are placed in the |1> quantum state, so as to use the auxiliary quantum bits as control quantum bits to activate the CZ gate between the target quantum bit pairs; The CCZS gate is used to construct the equivalent gate structure circuit of the CZ gate in the quantum approximate optimization quantum circuit, and the CZ gate equivalent gate structure circuit is used to realize the local fully connected CZ gate between the target quantum bits.

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