title: Molecular beam epitaxy growth and post-growth annealing of FeSe films on SrTiO3: a scanning tunneling microscopy study.
abstract: Low temperature scanning tunneling microscopy and spectroscopy are used to investigate the atomic and electronic structure evolution of FeSe films grown on SrTiO3 as a function of post-growth annealing. Single unit cell FeSe films are found to bond strongly with the underlying substrate, and become superconductive with diminishing chemical bond disorders at the interface via post-annealing. For thicker FeSe films, post-annealing removes excess Se in the films and leads to a transition from semiconductor into metallic behaviors. In double and multilayer films, strain-induced complex textures are observed and suggested to be the main cause for the absent superconductivity.
authors.affiliation: State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
authors.forename: Jun-Ping
authors.initials: JP
authors.lastname: Peng
authors.forename: Hui-Min
authors.initials: HM
authors.lastname: Zhang
authors.forename: Wen-Hao
authors.initials: WH
authors.lastname: Zhang
authors.forename: Hao
authors.initials: H
authors.lastname: Ding
authors.forename: Peng
authors.initials: P
authors.lastname: Deng
authors.forename: Kai
authors.initials: K
authors.lastname: Chang
authors.forename: Can-Li
authors.initials: CL
authors.lastname: Song
authors.forename: Shuai-Hua
authors.initials: SH
authors.lastname: Ji
authors.forename: Lili
authors.initials: L
authors.lastname: Wang
authors.forename: Ke
authors.initials: K
authors.lastname: He
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Qi-Kun
authors.initials: QK
authors.lastname: Xue
authors.forename: Xu-Cun
authors.initials: XC
authors.lastname: Ma