Two-dimensional weak anti-localization in Bi2Te3 thin film grown on Si(111)-(7×7) surface by molecular beam epitaxy

Result date: 01/01/2013
Author: A. Roy
Institute: Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758, USA
Publication: Appl. Phys. Lett.
Instrument: MBE Systems
We report on low temperature transport studies of Bi2Te3 topological insulator thin films grown on Si(111)-(7?×?7) surface by molecular beam epitaxy. A sharp increase in the magnetoresistance with magnetic field at low temperature indicates the existence of weak anti-localization. The measured weak anti-localization effect agrees well with the Hikami-Larkin-Nagaoka model, and the extracted phase coherence length shows a power-law dependence with temperature indicating the existence of a two-dimensional system. An insulating ground state has also been observed at low temperature showing a logarithmic divergence of the resistance that appears to be the influence of electron-electron interaction in a two-dimensional system.