2008/11/19 by Jian Li, Rui-Lin Chu, J. K. Jain +1 · 1 citation
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.dis-nn
paper · pdf · doi:10.1103/physrevlett.102.136806
published as Phys. Rev. Lett 102, 136806 (2009) · 4 pages, 4 figures
arxiv created 2008/11/19 · arxiv updated 2009/12/01
Disorder plays an important role in two dimensions, and is responsible for striking phenomena such as metal insulator transition and the integral and fractional quantum Hall effects. In this paper, we investigate the role of disorder in the context of the recently discovered topological insulator, which possesses a pair of helical edge states with opposing spins moving in opposite directions and exhibits the phenomenon of quantum spin Hall effect. We predict an unexpected and nontrivial quantum phase termed "topological Anderson insulator," which is obtained by introducing impurities in a two-dimensional metal; here disorder not only causes metal insulator transition, as anticipated, but is fundamentally responsible for creating extended edge states. We determine the phase diagram of the topological Anderson insulator and outline its experimental consequences.