Majorana Fermions Under Stress

ORAL

Abstract

Spin-orbit coupled semiconductor nanowires with Zeeman splitting in proximity contact with bulk s-wave superconductivity have recently been proposed as a promising platform for realizing Majorana fermions. However, in this setup the chemical potential of the nanowire is generally pinned by the Fermi surface of the superconductor. This makes the tuning of the chemical potential by external electrical gates, a crucial requirement for unambiguous detection of Majorana fermions, very challenging in experiments. Here we show that tunable topological superconducting regime supporting Majorana fermions can be realized in semiconductor nanowires using uniaxial stress. For n-type nanowires the uniaxial stress tunes the effective chemical potential, while for p-type systems the effective pairing may also be modified by stress, thus significantly enhancing the topological minigap. The required stress is within current experimental reach using conventional piezo crystals.

–

Authors

  • Ming Gong

    Department of Physics, The University of Texas at Dallas, Richardson, TX, 75080 USA, Washington State University, Department of Physics, the University of Texas at Dallas, The University of Texas at Dallas, Department of Physics, The University of Texas at Dallas, Department of Physics, The University of Texas at Dallas, Richardson, TX, 75080

  • Li Mao

    Department of Physics, The University of Texas at Dallas, Richardson, TX, 75080 USA, Department of Physics, the University of Texas at Dallas, Richardson, TX, 75080 USA

  • Sumanta Tewari

    Department of Physics and Astronomy, Clemson University, Clemson, SC, 29634 USA

  • Chuanwei Zhang

    Department of Physics, The University of Texas at Dallas, Richardson, TX, 75080 USA, Department of Physics, the University of Texas at Dallas, Department of Physics, The University of Texas at Dallas, Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, USA