title: Tunable interaction-induced localization of surface electrons in antidot nanostructured Bi2Te3 thin films.
abstract: Recently, a logarithmic decrease of conductivity has been observed in topological insulators at low temperatures, implying a tendency of localization of surface electrons. Here, we report quantum transport experiments on the topological insulator Bi2Te3 thin films with arrayed antidot nanostructures. With increasing density of the antidots, a systematic decrease is observed in the slope of the logarithmic temperature-dependent conductivity curves, indicating the electron-electron interaction can be tuned by the antidots. Meanwhile, the weak antilocalization effect revealed in magnetoconductivity exhibits an enhanced dominance of electron-electron interaction among decoherence mechanisms. The observation can be understood from an antidot-induced reduction of the effective dielectric constant, which controls the interactions between the surface electrons. Our results clarify the indispensable role of the electron-electron interaction in the localization of surface electrons and indicate the localization of surface electrons in an interacting topological insulator.
authors.affiliation: Department of Physics, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
authors.forename: Hong-Chao
authors.initials: HC
authors.lastname: Liu
authors.forename: Hai-Zhou
authors.initials: HZ
authors.lastname: Lu
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: He
authors.forename: Baikui
authors.initials: B
authors.lastname: Li
authors.forename: Shi-Guang
authors.initials: SG
authors.lastname: Liu
authors.forename: Qing Lin
authors.initials: QL
authors.lastname: He
authors.forename: Gan
authors.initials: G
authors.lastname: Wang
authors.forename: Iam Keong
authors.initials: IK
authors.lastname: Sou
authors.forename: Shun-Qing
authors.initials: SQ
authors.lastname: Shen
authors.forename: Jiannong
authors.initials: J
authors.lastname: Wang
keywords: antidot; electron−electron interaction; surface states; topological insulator; weak antilocalization effect