题 目：Exact Fisher zeros and thermofield dynamics across a quantum critical point
报告人：邹海源，华东师范大学
时 间：2024年7月18日 2:00 PM
地 点：物理学院LE201
邀请人：杨丽平
报告摘要：By setting the inverse temperature loose to occupy the complex plane, Michael E. Fisher showed that the zeros of the complex partition function, if approaching the real axis, reveal a thermodynamic phase transition. More recently, Fisher zeros have been used to mark the dynamical phase transition in quench dynamics. The success of Fisher zeros however seems limited, and it is unclear how they can be employed to shed light on quantum phase transitions or the non-unitary dynamics of open quantum systems. Here we answer this question by a comprehensive analysis of the one-dimensional transverse field Ising model. We exhaust all the Fisher zeros to show that in the thermodynamic limit they congregate into a remarkably simple pattern in the form of continuous open or closed lines. These Fisher lines evolve smoothly as the coupling constant is tuned, and a qualitative change identifies the quantum critical point.
邹海源，华东师范大学青年研究员。本科毕业于山东大学，博士毕业于爱荷华大学。先后在匹兹堡大学和上海交通大学李政道研究所进行博士后研究，于2021年底入职华东师范大学。主要从事强关联多体系统计算和理论研究，重点关注张量网格算法的发展和应用，并结合不同理论手段，探索多体模型中的新奇物态、量子临界行为以及其内在统计规律。