title: Spin polarization and transport of surface states in the topological insulators Bi2Se3 and Bi2Te3 from first principles.
abstract: We investigate the band dispersion and the spin texture of topologically protected surface states in the bulk topological insulators Bi2Se3 and Bi2Te3 by first-principles methods. Strong spin-orbit entanglement in these materials reduces the spin polarization of the surface states to ∼50% in both cases; this reduction is absent in simple models but of important implications to essentially any spintronic application. We propose a way of controlling the magnitude of spin polarization associated with a charge current in thin films of topological insulators by means of an external electric field. The proposed dual-gate device configuration provides new possibilities for electrical control of spin.
authors.affiliation: Department of Physics, University of California, Berkeley, California 94720, USA.
authors.forename: Oleg V
authors.initials: OV
authors.lastname: Yazyev
authors.forename: Joel E
authors.initials: JE
authors.lastname: Moore
authors.forename: Steven G
authors.initials: SG
authors.lastname: Louie