Helical edge states induced by lateral spin-orbit coupling

Abstract

The presence of edges locally breaks the inversion symmetry of heterostructures and gives rise to lateral (edge) spin-orbit coupling (SOC), which, under some conditions, can lead to the formation of helical edge states. If the edge SOC is strong enough, the helical edge states can penetrate the band-gap and be energetically isolated from the bulk-like states. As a result backward scattering is suppressed, dissipationless helical edge channels protected against time-inversion symmetric perturbations emerge, and the system behaves as a 2D topological insulator (TI). However, unlike in previous works on TIs, the mechanism proposed here for the creation of protected helical edge states relies on the strong edge SOC rather than on band inversion.

This paper has been withdrawn by the author due to some wrong conclusions extracted from an oversimplified model

References in corpus (9)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Evidence for Helical Edge Modes in Inverted InAs/GaSb Quantum Wells
• Quantum Spin Hall Effect in Inverted Type II Semiconductors
• The Helical Liquid and the Edge of Quantum Spin Hall Systems
• Quantum Spin Hall Effect and Enhanced Magnetic Response by Spin-Orbit Coupling
• Opposite spin accumulations on the transverse edges by the confining potential
• Spin Hall Effect and Spin Orbit coupling in Ballistic Nanojunctions
• Interface states in two-dimensional electron systems with spin-orbital interaction