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

Abstract

We have clarified that a topological insulator, Bi _2 Te _2 Se, 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.

Keywords

• gigantic Rashba effect
• spin-ARPES
• topologial insulator
• 73.20.-r
• 79.60.-i
• 71.70.Ej