Low temperature magnetoresistance studies in MBE grown topological insulator thin films

POSTER

Abstract

We studied low temperature magnetoresistance in molecular beam epitaxy grown topological insulator Bi$_2$Se$_3$ and Bi$_2$Te$_3$ thin films. The surface and structural characterization of the grown films showed smooth epitaxial growth on Si(111). The magnetoresistance has been measured at low temperatures (2 - 20 K) with magnetic fields upto 9 T. The full range perpendicular field magnetoresistance has been explained with the original Hikami-Larkin-Nagaoka theory. Altshuler-Aronov theory of localization has been used to understand the full range parallel field magnetoresistance. Various scattering times have been estimated by fitting the magnetoresistance data with the theory. It is shown that the Zeeman effect is not needed to explain the magnetoresistance and has not been considered in the theory either. The angle dependent anisotropic magnetoresistance has also been observed and explained using the above theories.

*This work is funded by NRI - SWAN.

Authors

  • Rik Dey

    • Microelectronics Research Center, Univ of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin, TX
    • Microelectronics Research Center, The University of Texas at Austin

  • Anupam Roy

    • Microelectronics Research Center, Univ of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin, TX

  • Tanmoy Pramanik

    • Microelectronics Research Center, Univ of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin, TX
    • Microelectronics Research Center, The University of Texas at Austin

  • Samaresh Guchhait

    • The University of Texas at Austin
    • Microelectronics Research Center, Univ of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin, TX

  • Sushant Sonde

    • Microelectronics Research Center, Univ of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin

  • Amritesh Rai

    • Univ of Texas, Austin
    • Microelectronics Research Center, Univ of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin, TX
    • Microelectronics Research Center, The University of Texas at Austin

  • Sarmita Majumder

    • Microelectronics Research Center, Univ of Texas at Austin

  • Bahniman Ghosh

    • Microelectronics Research Center, Univ of Texas at Austin
    • Microelectronics Research Center, The University of Texas at Austin

  • Leonard F. Register

    • Microelectronics Research Center, Univ of Texas at Austin
    • Univ of Texas, Austin
    • Microelectronics Research Center, The University of Texas at Austin

  • Sanjay Banerjee

    • Microelectronics Research Center, Univ of Texas at Austin
    • Univ of Texas, Austin
    • Microelectronics Research Center, The University of Texas at Austin, TX
    • Microelectronics Research Center, The University of Texas at Austin