[理论室报告] Topological Band Theory for Non-Hermitian Hamiltonians
摘要：Recently, there have been many experimental realizations of the non-Hermitian Hamiltonians in both open quantum systems and classical wave systems with gain or loss. I will show that the non-Hermitian Hamiltonians host topological classification very differently from the Hermitian ones. There are non-trivial generalizations of the Chern number in two dimensions, and a new classification in one dimension, which is based on the energy dispersion rather than the Bloch state.
I will first start talking about the basics of the non-Hermitian Hamiltonians, and then introduce the topological band theory, by explicitly showing the topological invariants. I will also talk about the non-Hermitian bulk-edge correspondence as well as the phase diagram for topological phase transitions, if there is time.