中国科学院化学研究所史强团队研究了基于路径积分表达式导数的非对角基集上的时间演化矩阵乘积算子方法。这一研究成果于2025年6月16日发表在《物理评论A》杂志上。

时间演化矩阵积算子（TEMPO）方法是模拟开放系统量子动力学的有力工具。通常，它用于对角系统浴耦合问题，其中离散影响泛函的分析表达式是可用的。在这项工作中，研究组的目标是通过扩展TEMPO算法以适应任意基集来解决与非对角耦合相关的问题。 

所提出的方法基于计算广义影响泛函在增加一个时间步长时的离散化路径积分表达式的导数，这产生了一个适用于非对角基组和任意数量的非计算浴的运动方程。然后通过对得到的微分方程进行积分，得到广义影响函数。然后通过模拟与两者耦合的单量子比特和双量子比特系统来测试新方法的适用性??- and ??-类型浴。

附：英文原文

Title: Time-evolving matrix product operator method in a nondiagonal basis set based on the derivative of the path-integral expression

Author: Shuocang Zhang, Qiang Shi

Issue&Volume: 2025/06/16

Abstract: The time-evolving matrix product operator (TEMPO) method is a powerful tool for simulating open system quantum dynamics. Typically, it is used in problems with diagonal system-bath coupling, where analytical expressions for discretized influence functional are available. In this work, we aim to address issues related to off-diagonal coupling by extending the TEMPO algorithm to accommodate arbitrary basis sets. The proposed approach is based on computing the derivative of the discretized path-integral expression of a generalized influence functional when increasing one time step, which yields an equation of motion valid for a nondiagonal basis set and an arbitrary number of noncommuting baths. The generalized influence functional is then obtained by integrating the resulting differential equation. The applicability of the new method is then tested by simulating one- and two-qubit systems coupled to both - and -type baths.

DOI: 10.1103/2tdf-q8fp

Source: https://journals.aps.org/pra/abstract/10.1103/2tdf-q8fp