关键词: 量子相位估计, CPU集群, MPI, HHL算法, 负载均衡

Abstract: Quantum computing is a new computing mode that follows the laws of quantum mechanics to regulate and control quantum information units to perform calculations,while the quantum algorithm is composed of a series of quantum gates whose realized form is quantum circuit.Quantum circuits are circuits that operate on qubits,using qubits as the basic storage unit to connect quantum logic gates to achieve specific computing functions.This paper uses the MPI+OpenMP hybrid parallel programming model on the “Songshan” supercomputer to realize the construction of large-scale quantum circuits by splitting them into different nodes,which speeds up the construction of circuits.For the communication problem between nodes,serialization and deserialization functions are designed to ensure the transmission of data between nodes.Aiming at the exponential difference in the amount of tasks allocated by each node,an optimized method of splitting the task amount and round-robin processing of each node is designed to achieve load balance between nodes.Finally,the construction of a large-scale quantum phase estimation circuit is successfully implemented on the supercomputer CPU cluster.Compared with a single node,the speedup ratio of 8.63 is achieved.The HHL algorithm is used to verify the correctness of the designed parallel phase estimation sub-module,which provides a reference for the implementation of large-scale HHL algorithm on the supercomputing platform.

Key words: Quantum phase estimation, CPU cluster, MPI, HHL algorithm, Load balancing