專題演講 Seminar

2022/12/20(Tue)     10:30 -12:00    一樓演講廳 1F, Auditorium
視訊演講 Video Seminar [ Meeting Link / ID: 2516 903 8978 / Password: 123456 ]

Title

Quantum matters with crystalline symmetry

Speaker

黃聖傑博士 (Max Planck Institute for the Physics of Complex Systems, Dresden, Germany)

Dr. Sheng-Jie Huang (Max Planck Institute for the Physics of Complex Systems, Dresden, Germany)

Abstract

Abstract: Symmetry has been an important organizing principle of quantum matters. A large class of phases of matter can be characterized by the way the symmetry is implemented and its non-trivial interplay with the entanglement structure in the many-body wavefunctions. A remarkable progress has been made during the last fifteen years on the classification, characterization, and experimental realization of topological quantum matters. This includes the discovery of many new families of quantum materials such as various topological insulators and semimetals, in which crystalline symmetries often play an important role. In this talk, I will introduce a general framework to classify and characterize topological phases with crystalline symmetry. In particular, I will show that topological phases protected by the crystalline symmetry an be adiabatically deformed into a special class of states called topological crystals, which are real-space assembly of lower-dimensional topological states with respect to the crystalline symmetry. This approach provides a simple physical picture of crystalline topological phases, and also allows one to understand various characteristic boundary properties such as higher-order topology. It also provides a guiding principle to obtain effective field theories that capture the topological responses. I will then discuss a generalization of this framework to the problem of classifying interacting Dirac semimetals.

Language

演講語言 (Language): in English