1. Imaginary-time Mpemba effect in quantum many-body systems
- Author
-
Chang, Wei-Xuan, Yin, Shuai, Zhang, Shi-Xin, and Li, Zi-Xiang
- Subjects
Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Statistical Mechanics ,Quantum Physics - Abstract
Various exotic phenomena emerge in non-equilibrium quantum many-body systems. The Mpemba effect, denoting the situation where a hot system freezes faster than the colder one, is a counterintuitive non-equilibrium phenomenon that has attracted enduring interest for more than half a century. In this Letter, we report a novel phenomenon of the Mpemba effect in the imaginary-time relaxation dynamics in quantum many-body systems, dubbed as imaginary-time Mpemba effect (ITME). Through numerically exact quantum Monte-Carlo (QMC) simulation, we unambiguously demonstrate that in different classes of interacting quantum models, the initial states with higher energy are relaxed faster than lower-energy initial states in the process of imaginary-time relaxation. The emergence of ITME is intimately associated with the low-energy excitations in quantum many-body systems. More crucially, since imaginary-time dynamics is broadly applied in numerical simulation on the quantum many-body ground states, the discovery of ITME potentially provides a new pathway to expedite the quantum many-body computation, particularly for QMC involving the sign problem., Comment: 4.5+8 pages, 4+6 figures
- Published
- 2024