Classification of topological phases in one dimensional interacting non-Hermitian systems and emergent unitarity

by Wenjie Xi (Southern University of Science and Technology)

Wednesday 9 Sept 2020, 14:00 → 16:00 Asia/Shanghai

ONLINE

Abstract

Recently, the topological properties of non-Hermitian Hamiltonians have drawn much attention. Studies have focused intensively on topological phases in non-Hermitian free fermion and the phase transitions among them. Unfortunately, a general classification scheme of topological phases in interacting non-Hermitian systems is still lacking. In this seminar, I attempt to classify topological phases in 1D interacting non-Hermitian systems. I begin with the non-Hermitian generalization of the Su-Schrieffer-Heeger (SSH) model and discuss its many-body topological Berry phase, which is well defined for all interacting quasi-Hermitian systems (non-Hermitian systems that have real energy spectrum). I then demonstrate that the classification of topological phases for quasi-Hermitian systems is exactly the same as their Hermitian counterparts. Finally, we find that topological phases in generic 1D non-Hermitian systems with local interactions still have a one to one correspondence to their Hermitian counterpart. Thus, we conjecture that the classification of topological phases for generic 1D interacting non-Hermitian systems is still exactly the same as Hermitian systems.

Biography

I am currently a graduate student in Institute for Quantum Science and Engineering & Department of Physics, Southern University of Science and Technology, Shenzhen.

Chair

Prof. Wei Ku

Division

Condensed Matter

Other information

Venue: TDLI Meeting Room 200

Here is the Zoom link if you prefer to join us remotely:

https://zoom.com.cn/j/96916087603

Password: 297019