Second-Order Topological Phases in Non-Hermitian Systems

• Published in: Physical review letters Vol. 122; no. 7; p. 076801
• Main Authors: Liu, Tao, Zhang, Yu-Ran, Ai, Qing, Gong, Zongping, Kawabata, Kohei, Ueda, Masahito, Nori, Franco
• Format: Journal Article
• Language: English
• Published: United States 22.02.2019

A d-dimensional second-order topological insulator (SOTI) can host topologically protected (d-2)-dimensional gapless boundary modes. Here, we show that a 2D non-Hermitian SOTI can host zero-energy modes at its corners. In contrast to the Hermitian case, these zero-energy modes can be localized only...