title: Fermi-level tuning of epitaxial Sb2Te3 thin films on graphene by regulating intrinsic defects and substrate transfer doping.
abstract: High-quality Sb2Te3 films are obtained by molecular beam epitaxy on a graphene substrate and investigated by in situ scanning tunneling microscopy and spectroscopy. Intrinsic defects responsible for the natural p-type conductivity of Sb2Te3 are identified to be the Sb vacancies and Sb(Te) antisites in agreement with first-principles calculations. By minimizing defect densities, coupled with a transfer doping by the graphene substrate, the Fermi level of Sb2Te3 thin films can be tuned over the entire range of the bulk band gap. This establishes the necessary condition to explore topological insulator behaviors near the Dirac point.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Yeping
authors.initials: Y
authors.lastname: Jiang
authors.forename: Y Y
authors.initials: YY
authors.lastname: Sun
authors.forename: Mu
authors.initials: M
authors.lastname: Chen
authors.forename: Yilin
authors.initials: Y
authors.lastname: Wang
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
authors.forename: Canli
authors.initials: C
authors.lastname: Song
authors.forename: Ke
authors.initials: K
authors.lastname: He
authors.forename: Lili
authors.initials: L
authors.lastname: Wang
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Qi-Kun
authors.initials: QK
authors.lastname: Xue
authors.forename: Xucun
authors.initials: X
authors.lastname: Ma
authors.forename: S B
authors.initials: SB
authors.lastname: Zhang