Disorder induced topological phases
Hsiu-Chuan Hsu1*, Tsung-Wei Chen2, Pok Man Chiu3, Po-Yao Chang3
1Graduate Institute of Applied Physics, National Chengchi University, Taipei, Taiwan
2Department of physics, National Sun Yat-sen University, Kaohsiung, Taiwan
3Department of physics, National Tsing Hua University, Hsinchu, Taiwan
* Presenter:Hsiu-Chuan Hsu, email:hchsu888@gmail.com
Disorder induced topological phases are shown to exist in equilibrium systems, as well as in quench dynamics. In this talk, I will present our findings in both regimes for the one-dimensional Su-Schrieffer–Heeger (SSH) model. First, I will show the topological Anderson insulating phase in an equilibrium system. For the long-range SSH model, it is shown that disorder drives topological phase transitions between different topological phases. The phase diagram is identified with the calculation of winding number and localization length. The mechanism is explained by band gap renormalization and Anderson localization. Secondly, I will address the disorder induced topology in quench dynamics. The nontrivial topology is confirmed by entanglement spectrum, Berry phase and the quantization of the dynamical Chern number. The role of disorder in quench dynamics will be discussed.

Keywords: Anderson localization, Topological insulators, Green's function methods