报告题目：Many-body non-Hermitian skin effect induced by a dynamic gauge coupling

报告人：郑炜 副教授（中国科学技术大学）

报告时间：2023年5月19日（周五）下午5:00

报告地点：光电所二层报告厅

报告摘要：  

For a non-Hermitian Hamiltonian its spectrum and way function is sensitive to the boundary conditions. For open boundary condition all particles are cumulated at the boundary. This phenomenon is called non-Hermitian skin effect (NHSE). The NHSE is found to have dramatic influence on the system’s band and spectral topology, as well as the spectral symmetry [62–64] and dynamics. At single-particle level the NHSE has been well studied, however the many-body NHSE in the presence of strong interactions is not fully understood. In this talk, I will introduce our works on an atom-cavity hybrid system where fermionic atoms in a one-dimensional lattice are subject to a cavity-induced dynamic gauge potential. The gauge coupling leads to highly-degenerate steady states in which the fermions accumulate to one edge of the lattice under an open boundary condition. Such a phenomenon originates from the many-body Liouvillian super-operator of the system, which, being intrinsically non-Hermitian, is unstable against boundary perturbations and manifests the non-Hermitian skin effect.

报告人简介：  

郑炜，中国科学技术大学物理学院副教授。2012年于中山大学获得博士学位。2012年至2019年先后在清华大学高等研究院、剑桥大学卡文迪许实验室、以及香港大学物理系从事博士后研究工作。2020年1月加入中国科学技术大学至今。主要研究方向是基于超冷原子平台的量子多体物理，在Nature Physics、Physical Review Letters、Science Bulletin等学术期刊上发表论文20余篇。近年来主要学术成果包括：预言了自旋轨道耦合玻色-爱因斯坦凝聚体中的旋子结构，后被中科大实验组证实；提出驱动光晶格来模拟拓扑物态的方案，后被瑞士苏黎世工业技术学院实验组实现；发现了驱动玻色-爱因斯坦凝聚体中的非线性阻尼等。