Ultrafast Bulk and Surface Dynamics of Bi2Se3 Measured by Time-Resolved ARPES

ORAL

Abstract

We investigated the nonequilibrium carrier dynamics of the topological insulator Bi$_2$Se$_3$ using femtosecond time- and angle- resolved photoemission spectroscopy. Optical excitation leads to a metastable population of bulk carriers due to the presence of the bandgap. We discuss the coupling of these carriers to the Dirac surface state, which results in a long-lived nonequiilibrium surface carrier distribution. We will comment on the implications for topological insulator device applications.

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Authors

  • Jonathan Sobota

    • Stanford University

  • Shuolong Yang

    • Stanford University

  • James Analytis

    • Stanford University

  • Yulin Chen

    • Stanford University

  • Ian Fisher

    • Stanford Unversity

  • Patrick Kirchmann

    • Fritz Haber Institute of the Max Planck Society

  • Zhi-Xun Shen

    • Stanford University