title: Layer-by-layer entangled spin-orbital texture of the topological surface state in Bi2Se3.
abstract: We study Bi(2)Se(3) by polarization-dependent angle-resolved photoemission spectroscopy and density-functional theory slab calculations. We find that the surface state Dirac fermions are characterized by a layer-dependent entangled spin-orbital texture, which becomes apparent through quantum interference effects. This explains the discrepancy between the spin polarization obtained in spin and angle-resolved photoemission spectroscopy-ranging from 20% to 85%-and the 100% value assumed in phenomenological models. It also suggests a way to probe the intrinsic spin texture of topological insulators, and to continuously manipulate the spin polarization of photoelectrons and photocurrents all the way from 0 to ±100% by an appropriate choice of photon energy, linear polarization, and angle of incidence.
authors.affiliation: Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
authors.forename: Z-H
authors.initials: ZH
authors.lastname: Zhu
authors.forename: C N
authors.initials: CN
authors.lastname: Veenstra
authors.forename: G
authors.initials: G
authors.lastname: Levy
authors.forename: A
authors.initials: A
authors.lastname: Ubaldini
authors.forename: P
authors.initials: P
authors.lastname: Syers
authors.forename: N P
authors.initials: NP
authors.lastname: Butch
authors.forename: J
authors.initials: J
authors.lastname: Paglione
authors.forename: M W
authors.initials: MW
authors.lastname: Haverkort
authors.forename: I S
authors.initials: IS
authors.lastname: Elfimov
authors.forename: A
authors.initials: A
authors.lastname: Damascelli