Localization of edge electrons in a 2D topological insulator strip
M. V. Entin, L. I. Magarill
Rzanov Institute of Semiconductor Physics SB of the RAS, 630090 Novosibirsk, Russia
Novosibirsk State University, 630090 Novosibirsk, Russia
Abstract
The edge states in an ideal topological insulator are
topologically protected. The same-spin edge states propagate in opposite
directions on different sides of the strip and do not mix by tunneling. The
interaction with impurities results in interedge same-spin backscattering. At
low temperatures, the localization occurs and the conductance of a long wire
vanishes. We study this localization in a numerical model of localized
scatterers. The localization length is found to be exponentially long with
respect to the strip width. The intraedge inelastic forward scattering
destroys the coherence. These processes caused by phonons were explored. The
transition temperature between kinetic and localization behaviors has been
found.