美国蒙大拿州立大学Martín A. Mosquera团队近日研究了多参考系统的时变耦合聚类理论。相关论文于2025年7月31日发表在《物理评论A》杂志上。

研究组提出了在一般量子力学状态下开始的多参考电子系统传播的耦合-热计理论。它们的形式化是基于对修正克氏算子的无穷小分析，并从中提取出一组附加算子及其运动方程。然后，可以对这些传感器运算符进行主题化，以便以扩展尺寸的方式计算感兴趣的电子特性。

研究组还分析了线性叠加的自由传播方程。在这种情况下，他们推导了可观测物的非对称矩阵元素，以及一个再对称因子，使它们与量子力学对应物保持一致。这种形式化被应用到一个具有哈伯德样哈密顿量的四电子/四能级模型中，研究组表明它再现了可观测值、种群和相干的数值精确结果。

附：英文原文

Title: Time-dependent coupled-cluster theory of multireference systems

Author: Martín A. Mosquera

Issue&Volume: 2025/07/31

Abstract: In this work we present a coupled-cluster theory for the propagation of multireference electronic systems initiating at general quantum mechanical states. Our formalism is based on the infinitesimal analysis of modified cluster operators, from which we extract a set of additional operators and their equations of motion. These cluster operators then can be used to compute electronic properties of interest in a size-extensive manner. The equations derived herein are also studied for the free propagation of linear superpositions. In this regime, we derive asymmetric matrix elements for observables, and a resymmetrization factor so they become consistent with their quantum mechanical counterparts. Our formalism is applied to a four-electron/four-level model with a Hubbard-like Hamiltonian, where we show that it reproduces the numerically exact results for observables, populations, and coherences.

DOI: 10.1103/y9y8-vjrv

Source: https://journals.aps.org/pra/abstract/10.1103/y9y8-vjrv