Transport in Topological Insulator Thin Films

ORAL

Abstract

We report on electronic transport measurements on Bi2Se3 thin-film devices and show that an ambipolar modulation can be achieved via the electric field effect by using a top-gate with a high-k dielectric insulator. By analyzing the evolution of the weak anti-localization magnetoconductance behavior with respect to gate voltage and temperature, we find that we are able to modulate the effective number of channels, demonstrating that the coherent coupling between the surface and the bulk is tunable. Moreover, we investigate the formation and behavior of tunable p-n junctions on thin-film devices with multiple local top-gates.

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Authors

  • V. Fatemi

    MIT, Department of Physics, MIT, Department of Physics, MIT, Cambridge, USA

  • H. Steinberg

    MIT, Department of Physics, MIT, Cambridge, USA

  • Jean-Baptiste Laloe

    MIT

  • F. Katmis

    MIT, Francis Bitter Magnet Lab, Francis Bitter Magnet Lab, MIT, Cambridge, MA, MIT, Department of Physics, MIT, Cambridge, USA

  • Lucas Orona

    MIT

  • Jagadeesh S. Moodera

    Massachusetts Institute of Technology, MIT, Francis Bitter Magnet Lab, Francis Bitter Magnet Lab and Physics Department, MIT, Cambridge, MA, MIT, Department of Physics, MIT, Cambridge, USA, Francis Bitter Magnet Lab., FBML and Physics Dept., MIT

  • Pablo Jarillo-Herrero

    MIT, Massachusetts Institute of Techology, Physics Department, MIT, Cambridge, MA, Department of Physics, MIT, Cambridge, USA, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 USA, Massachusetts Institute of Technology