title: Catalyst-free growth of millimeter-long topological insulator Bi₂Se₃ nanoribbons and the observation of the π-Berry phase.
abstract: We report the growth of single-crystalline Bi(2)Se(3) nanoribbons with lengths up to several millimeters via a catalyst-free physical vapor deposition method. Scanning transmission electron microscopy analysis reveals that the nanoribbons grow along the (112̅0) direction. We obtain a detailed characterization of the electronic structure of the Bi(2)Se(3) nanoribbons from measurements of Shubnikov-de Haas (SdH) quantum oscillations. Angular dependent magneto-transport measurements reveal a dominant two-dimensional contribution originating from surface states. The catalyst-free synthesis yields high-purity nanocrystals enabling the observation of a large number of SdH oscillation periods and allowing for an accurate determination of the π-Berry phase, one of the key features of Dirac fermions in topological insulators. The long-length nanoribbons open the possibility for fabricating multiple nanoelectronic devices on a single nanoribbon.
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60565, United States. lfang@anl.gov
authors.forename: L
authors.initials: L
authors.lastname: Fang
authors.forename: Y
authors.initials: Y
authors.lastname: Jia
authors.forename: D J
authors.initials: DJ
authors.lastname: Miller
authors.forename: M L
authors.initials: ML
authors.lastname: Latimer
authors.forename: Z L
authors.initials: ZL
authors.lastname: Xiao
authors.forename: U
authors.initials: U
authors.lastname: Welp
authors.forename: G W
authors.initials: GW
authors.lastname: Crabtree
authors.forename: W-K
authors.initials: WK
authors.lastname: Kwok