一种提高量子线路保真度的转换方法

A conversion method for improving fidelity of quantum circuits

在实际量子计算中,量子比特和量子操作表现出不同的品质特性,从而影响量子计算结果的保真度。而量子受控非门(CNOT门)错误率在品质特性中占据主要地位。提出了一种既能满足连通约束又能提高保真度的量子线路转换方法,该方法先通过Floyd算法找出量子位移动路径,基于该路径上存在的一个或多个双量子比特门执行的成功率,构建启发式函数,以此来选择线路中高保真度的交换方式。多个基准测试实验结果表明,与IBM Qiskit工具包中的SabreSwap和StochasticSwap算法相比,本工作所提方法在量子线路保真度方面分别提高了39.29%和36.06%。

In actual quantum computing,qubits and quantum operations exhibit different quality characteristics,which affect the fidelity of quantum computing results.While among the quality characteristics,the error rate of controlled-NOT(CNOT)quantum gate occupies a major position.This research proposes a quantum circuit conversion method that not only satisfies the connectivity constraints but also improves fidelity.The method first finds out the qubit moving path through Floyd algorithm,and constructs a heuristic function based on the success rate of one or more two-qubit gates on the path,then select the high-fidelity switching mode in this circuit.Multiple benchmark experiments show that compared with SabreSwap and StochasticSwap algorithms in IBM Qiskit toolkit,the proposed method improves the quantum line fidelity by 39.29%and 36.06%respectively.