title: Observation of time-reversal-protected single-dirac-cone topological-insulator states in Bi2Te3 and Sb2Te3.
abstract: We show that the strongly spin-orbit coupled materials Bi2Te3 and Sb2Te3 and their derivatives belong to the Z2 topological-insulator class. Using a combination of first-principles theoretical calculations and photoemission spectroscopy, we directly show that Bi2Te3 is a large spin-orbit-induced indirect bulk band gap (delta approximately 150 meV) semiconductor whose surface is characterized by a single topological spin-Dirac cone. The electronic structure of self-doped Sb2Te3 exhibits similar Z2 topological properties. We demonstrate that the dynamics of spin-Dirac fermions can be controlled through systematic Mn doping, making these materials classes potentially suitable for topological device applications.
authors.affiliation: Joseph Henry Laboratories of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: D
authors.initials: D
authors.lastname: Hsieh
authors.forename: Y
authors.initials: Y
authors.lastname: Xia
authors.forename: D
authors.initials: D
authors.lastname: Qian
authors.forename: L
authors.initials: L
authors.lastname: Wray
authors.forename: F
authors.initials: F
authors.lastname: Meier
authors.forename: J H
authors.initials: JH
authors.lastname: Dil
authors.forename: J
authors.initials: J
authors.lastname: Osterwalder
authors.forename: L
authors.initials: L
authors.lastname: Patthey
authors.forename: A V
authors.initials: AV
authors.lastname: Fedorov
authors.forename: H
authors.initials: H
authors.lastname: Lin
authors.forename: A
authors.initials: A
authors.lastname: Bansil
authors.forename: D
authors.initials: D
authors.lastname: Grauer
authors.forename: Y S
authors.initials: YS
authors.lastname: Hor
authors.forename: R J
authors.initials: RJ
authors.lastname: Cava
authors.forename: M Z
authors.initials: MZ
authors.lastname: Hasan