用经典计算机模拟量子计算机

摘要

Quantum state superposition and entanglement enable a quantum computer's exponen-tial speed-up in solving many crypto-significant hard problems, such as integer factorization, discrete logarithm, etc. In this paper, methods of modeling the quantum state superposition and entanglement, quantum bits and gates representations and multiple-bit computation prototype are given. Based on object-oriented Python, we provide a quantum simulator integrated with an API suite implementing the methods aforementioned. To ease the coding process, we designed a user-friendly interface, in-cluding realization of quantum circuits design, measurement result demonstration, statistic and other accessories. At the end of the paper, some experiments on quantum computing have been done with the software developed in this paper, and the experimental results are given. The experimental results are further analyzed with the principle of quantum computing to enhance the reader's understanding of quantum computing.%基于量子态的纠缠和叠加特性,量子计算机具有强大的并行运算能力,在某些数学问题上可为经典计算机所不能.自Shor算法提出以来,因其一经应用即可对现行主流公钥密码体制构成实际威胁,量子计算机的研究受到了广泛关注.本文分析量子计算机与经典计算机的差异,给出在经典计算机上模拟量子叠加态和量子纠缠特性以及施加多量子门的方法,并使用面向对象的架构编写模拟量子计算机的量子状态、量子门等主体模块,并为研究人员预留了设定不同退相干过程的接口.为了方便基于模拟量子计算机的量子软件开发,本文设计了涵盖量子线路设计、运行结果可视化、统计、存储等功能的人机交互界面.同时,在文章的最后一部分用本文开发的软件做了几个较为经典的量子计算方面的实验,给出实验结果,并结合量子计算的原理对实验结果进行分析,加深读者对量子计算的理解.