论文标题
基于非自动量子电路的概率假想时间演变算法
A Probabilistic Imaginary Time Evolution Algorithm Based on Non-unitary Quantum Circuit
论文作者
论文摘要
假想时间演变是一种应用于量子物理学的功能强大的工具，而现有的经典算法用于模拟假想时间的演变具有较高的计算复杂性，因为量子系统变得更大，更复杂。在这项工作中，我们提出了一种概率算法，用于基于非自动量子电路实现假想时间演变。我们通过求解包括H2，LIH分子和量子链的几个量子多体系统的基态能量来证明该方法的可行性。此外，我们分别在超导和捕获的离子云平台上进行实验，以找到H2的基态能及其最稳定的分子结构。我们还分析了该算法的成功概率，该算法是输出误差的多项式，并引入了一种通过重新排列哈密顿式术语来增加成功概率的方法。
Imaginary time evolution is a powerful tool applied in quantum physics, while existing classical algorithms for simulating imaginary time evolution suffer high computational complexity as the quantum systems become larger and more complex. In this work, we propose a probabilistic algorithm for implementing imaginary time evolution based on non-unitary quantum circuit. We demonstrate the feasibility of this method by solving the ground state energy of several quantum many-body systems, including H2, LiH molecules and the quantum Ising chain. Moreover, we perform experiments on superconducting and trapped ion cloud platforms respectively to find the ground state energy of H2 and its most stable molecular structure. We also analyze the successful probability of the algorithm, which is a polynomial of the output error and introduce an approach to increase the success probability by rearranging the terms of Hamiltonian.
