量子电子学报 ›› 2026, Vol. 43 ›› Issue (1): 120-130.doi: 10.3969/j.issn.1007-5461.2026.01.010

• 量子计算 • 上一篇    下一篇

量子近似优化算法在图着色中的应用

刘裕彤 , 李志强 *, 尹经纬   

  1. 扬州大学信息工程学院, 江苏 扬州 225127
  • 收稿日期:2024-06-19 修回日期:2024-09-24 出版日期:2026-01-28 发布日期:2026-01-28
  • 通讯作者: E-mail: yzqqLzq@163.com E-mail:E-mail: yzqqLzq@163.com
  • 作者简介:刘裕彤 ( 1999 - ), 江苏南通人, 研究生, 主要从事量子算法方面的研究。 E-mail: 1641248348@qq.com
  • 基金资助:
    国家自然科学基金 (62071240)

Application of quantum approximate optimization algorithm in graph coloring

LIU Yutong, LI Zhiqiang *, Yin Jingwei   

  1. College of Information Engineering, Yangzhou University, Yangzhou 225127, China
  • Received:2024-06-19 Revised:2024-09-24 Published:2026-01-28 Online:2026-01-28

摘要: 图着色问题属于NP完全问题, 目前尚未找到一种在所有情况下都能够在多项式时间内解决这类问题的算法。针对图着色问题, 本研究基于量子近似优化算法将其映射至量子比特并设计了量子电路。首先, 利用旋转算符和泡利算符对问题的经典伊辛模型进行量子化, 得到问题的哈密顿量。随后基于混合哈密顿量和问题哈密顿量设计了两种含参酉变换, 通过交替应用这两种酉变换得到问题哈密顿期望值。为提高正确解出现的概率, 在量子态演化的过程中使用Powell算法对参数进行优化以调整期望值。最后, 根据哈密顿量推导出算法的初始状态和所需的量子门, 生成量子电路, 并利用IBM量子框架Qiskit进行仿真实验。实验结果证实了该方案可以在多项式时间内以高概率获得问题解, 具备显著的指数级加速效果。

关键词: 量子计算, 量子近似优化算法, 量子电路, 哈密顿量, 图着色, 酉变换

Abstract: The graph coloring problem is classified as one of NP-complete problems, and currently there is no known algorithm that can solve such problems in polynomial time in all cases. In response to this issue, we map it to quantum bits and design a quantum circuit in this work based on the quantum approximate optimization algorithm (QAOA). Firstly, we quantize the classical Ising model of the problem using rotation operators and Pauli operators to derive the problem's Hamiltonian. Subsequently, two parameterized unitary transformations are designed based on the mixing Hamiltonian and the problem Hamiltonian, and the expectation value of the problem's Hamiltonian is obtained by alternately applying these two unitary transformations. Specifically, to increase the probability of obtaining the correct solution, the Powell algorithm is used to optimize the parameters during the quantum state evolution to adjust the expectation value. Finally, based on the Hamiltonian, the initial state and the required quantum gates of the algorithm are derived, the quantum circuit is generated, and simulation experiments are conducted using Qiskit quantum framework of IBM. The experimental results show that the proposed approach can obtain the solution of graph coloring problem with high probability in polynomial time, demonstrating a significant exponential speedup.

Key words: quantum computing, quantum approximate optimization algorithm, quantum circuit, Hamiltonian, graph coloring, unitary transformation

中图分类号: