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.
Liu, Y,王焕华；Wang, HH,Bian, G,et al. Interfacial Bonding and Structure of Bi2Te3 Topological Insulator Films on Si(111) Determined by Surface X-Ray Scattering[J]. PHYSICAL REVIEW LETTERS,2013,110(22):226103.
Liu, Y.,王焕华；Wang, HH.,Bian, G.,Zhang, Z.,Lee, SS.,...&Chiang, TC.(2013).Interfacial Bonding and Structure of Bi2Te3 Topological Insulator Films on Si(111) Determined by Surface X-Ray Scattering.PHYSICAL REVIEW LETTERS,110(22),226103.
Liu, Y,et al."Interfacial Bonding and Structure of Bi2Te3 Topological Insulator Films on Si(111) Determined by Surface X-Ray Scattering".PHYSICAL REVIEW LETTERS 110.22(2013):226103.