通过从实时量子模拟进行解析延拓实现量子系统的虚时演化
Imaginary time evolution of a quantum system through analytic continuation from real-time quantum simulation
AI总结：
本研究提出一种通过对测得的实时关联函数进行解析延拓来获取一般量子哈密顿量虚时演化的算法，并在IBM量子硬件上通过实例验证了该方法的有效性。
AI中文摘要：
尽管量子计算在实时量子系统模拟方面天然具有优势，但实现虚时演化（Imaginary-Time Evolution, ITE）相对更为困难。不过，ITE的量子实现既适用于经典实现存在符号问题的场景，也是在量子计算机上制备本征态的精确方法。本研究提出一种算法，通过对测得的实时关联函数进行解析延拓，以获取一般量子哈密顿量的ITE。我们在IBM量子硬件上对经典扩散过程的一维Fokker-Planck方程、一维量子力学散射中关联函数的虚时演化进行了模拟与演示，以验证该方法的有效性。
英文摘要：
Though quantum computing naturally offers an advantage for simulations of real-time quantum systems, implementing Imaginary-Time Evolution (ITE) is comparatively more difficult. Nevertheless, quantum implementations of ITE are useful both in cases where classical implementations have associated sign problems, and also as an exact method of preparing eigenstates on quantum computers. In this work we present an algorithm to obtain ITE of a generic quantum Hamiltonian by performing analytic continuation of measured real-time correlation functions. We present simulations and demonstrations on IBM quantum hardware of 1D Fokker-Planck equations for classical diffusion process and imaginary-time evolution of integrated correlation functions in 1D quantum mechanical scattering as examples to demonstrate the effectiveness of the method.
