title: In situ magnetotransport measurements in ultrathin Bi films: evidence for surface-bulk coherent transport.
abstract: We performed in situ magnetotransport measurements on ultrathin Bi(111) films [4-30 bilayers (BLs), 16-120 Å thick] to elucidate the role of bulk or surface states in the transport phenomena. We found that the temperature dependence of the film conductivity shows no thickness dependence for the 6-16 BL films and is affected by the electron-electron scattering, suggesting surface-state dominant contribution. In contrast, the weak antilocalization effect observed by applying a magnetic field shows clear thickness dependence, indicating bulk transport. This apparent inconsistency is explained by a coherent bulk-surface coupling that produces a single channel transport. For the films thicker than 20 BLs, the behavior changes drastically which can likely be interpreted as a bulk dominant conduction.
authors.affiliation: Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Aitani
authors.affiliation: Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Hirahara
authors.affiliation: Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Ichinokura
authors.affiliation: Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hanaduka
authors.affiliation: Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Dongyoon
authors.initials: D
authors.lastname: Shin
authors.affiliation: Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Shuji
authors.initials: S
authors.lastname: Hasegawa