The gigantic Rashba effect of surface states energetically buried in the topological insulator Bi2Te2Se

Abstract

We have clarified that a topological insulator, Bi2Te 2Se, shows two surface states with gigantic Rashba-type spin-splitting located at a binding energy deeper than the topological surface state. The magnitude of the Rashba parameter, as well as the momentum splitting, is found to be large enough to realize a number of nanometer-sized spintronic devices. This novel finding paves the way to studies of gigantic Rashba systems that are suitable for future spintronic applications. © 2014 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.