Fractional Quantum Hall States and Phase Transitions

Speaker
吴英海
Title
副教授
Affiliation
华中科技大学
Time
2025-10-16 (Thu) 10:00
Location
中科大上海研究院1号楼3楼报告厅(HFNL科研楼南楼A712、科大物质楼B1102同步视频)
Abstract

Speaker's Brief Introduction: 吴英海,2009年本科毕业于中国科学技术大学近代物理系,2014年博士毕业于美国宾夕法尼亚州立大学物理系,导师为Jainendra Jain,2014-2017年间在德国马普量子光学研究所J. Igancio Cirac理论组从事博士后研究。2017年8月至今为华中科技大学物理学院副教授。主要研究方向为强关联量子多体系统,已发表学术论文40余篇。

Abstract: Fractional quantum Hall states are canonical examples of topological phases driven by strong correlation. The conventional setting is electrons confined to two dimensions in solid state systems and exposed to a perpendicular magnetic field, but other scenarios have also been discussed and are under active investigations. In this talk, I will give a brief introduction to certain aspects of FQH states, particularly the composite fermion theory and non-Abelian anyons. FQH states cannot be distinguished by local order parameters associated with broken symmetry, but exhibit nontrivial ground state properties on high-genus surfaces, which motivated the notion of topological order. For phase transitions that involve FQH states, the Landau-Ginzburg-Wilson framework is not applicable. I will discuss some examples of such phase transitions in multi-component quantum Hall systems. It is proposed that the universal properties of the critical points are described by Chern-Simons-Higgs field theory.