title: Interfacial bonding and structure of Bi2Te3 topological insulator films on Si(111) determined by surface x-ray scattering.
abstract: Interfacial topological states are a key element of interest for topological insulator thin films, and their properties can depend sensitively on the atomic bonding configuration. We employ in situ nonresonant and resonant surface x-ray scattering to study the interfacial and internal structure of a prototypical topological film system: Bi2Te3 grown on Si(111). The results reveal a Te-dominated buffer layer, a large interfacial spacing, and a slightly relaxed and partially strained bottom quintuple layer of an otherwise properly stacked bulklike Bi2Te3 film. The presence of the buffer layer indicates a nontrivial process of interface formation and a mechanism for electronic decoupling between the topological film and the Si(111) substrate.
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA. yangliu3@aps.anl.gov
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.forename: H-H
authors.initials: HH
authors.lastname: Wang
authors.forename: G
authors.initials: G
authors.lastname: Bian
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.forename: S S
authors.initials: SS
authors.lastname: Lee
authors.forename: P A
authors.initials: PA
authors.lastname: Fenter
authors.forename: J Z
authors.initials: JZ
authors.lastname: Tischler
authors.forename: H
authors.initials: H
authors.lastname: Hong
authors.forename: T-C
authors.initials: TC
authors.lastname: Chiang