"Topological matter" refers to a new class of condensed matter system that possesses unique topological properties. The electronic properties in these materials are determined by the geometric nature of the electron wave functions in momentum space (more precisely, by their topological invariants). A key feature of topological materials is the bulk-boundary correspondence, which is that they can host conducting boundary mode, even when the bulk of the material is insulating. The introduction of topological concepts into condensed matter physics started from the study of the quantum Hall effect in two-dimensional electron gases and has since expanded to include three-dimensional crystals. Three-dimensional topological materials that have been discovered include topological insulators, topological semimetals, and topological superconductors. In this talk, I will briefly introduce the definitions and characteristics of several representative types of topological matter, providing an initial understanding of this important emerging field for students.

Speaker

 Prof. Hao Zheng

 School of Physics and Astronomy, SJTU

Time

        2024.10.9 12:00-13:30