Non-local electrostatic gating in Majorana nanowires

ORAL

Abstract

Ever since the predicted existence of Majorana Zero-Modes (MZMs), the building blocks of topological quantum computation in hybrid semiconductor-superconductor wires, experimental efforts to detect signatures of MZMs have mainly focused on tunneling experiments, culminating in the recent observation of quantized Majorana conductance. However, the local probes used in previous studies cannot unambiguously reveal the non-local separation of MZMs, the hallmark of topological superconductivity. Here we study non-local properties of MZMs in tunneling spectroscopy on InSb nanowires covered with epitaxial aluminium by using two separate gates underneath the superconductor, one to tune part of the wire into the topological phase and an additional remote gate to tune the potential at the far end of the topological section. By tuning the remote gate we observe zero-bias peak splitting in the local tunneling measurement, presumably due to variation in the overlap between MZMs at the two ends. In contrast, trivial Andreev Bounds States, identified by instability with respect to the local gates, are completely insensitive to the remote gate.

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Presenters

  • Jouri Bommer

    QuTech and Kavli Institute of Nanoscience, Delft University of Technology

Authors

  • Jouri Bommer

    QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Hao Zhang

    Tsinghua University, Beijing, China, Qutech, Delft University of Technology, QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Michiel De Moor

    QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Di Xu

    Qutech, Delft University of Technology, QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Sasa Gazibegovic

    Applied Physics, Eindhoven University of Technology, Eindhoven University of Technology, Applied Physics, Eindhoven Univ. of Technology, Department of Applied Physics, Eindhoven University of Technology, TU Eindhoven, Eindhoven University of Technology, Department of Applied Physics

  • Roy L. M. Op het Veld

    Department of Applied Physics, Eindhoven University of Technology, TU Eindhoven, Eindhoven University of Technology, Department of Applied Physics, Eindhoven University of Technology

  • Erik P. A. M. Bakkers

    Applied Physics, Eindhoven University of Technology, Eindhoven University of Technology, Applied Physics, Eindhoven Univ. of Technology, Department of Applied Physics, Eindhoven University of Technology, TU Eindhoven, Eindhoven University of Technology, Department of Applied Physics, Physics, TU Eindhoven

  • Mihir Pendharkar

    University of California - Santa Barbara, University of California Santa Barbara, Dept. of ECE, University of California Santa Barbara, Department of Electrical and Computer Engineering, University of California, Santa Barbara, Electrical and Computer Engineering, University of California, Santa Barbara, University of California Santa Barbara, Materials Engineering, University of California, Santa Barbara

  • Joon Sue Lee

    University of California - Santa Barbara, University of California Santa Barbara, Dept. of ECE, University of California Santa Barbara, California NanoSystems Institute, University of California, Santa Barbara, Department of Physics, The Pennsylvania State University, University of California, Santa Barbara

  • Chris Palmstrom

    University of California, Santa Barbara, University of California - Santa Barbara, University of California Santa Barbara, Electrical & Computer Engineering, University of California, Santa Barbara, ECE and Materials, University of California, Santa Barbara, Dept. of ECE, University of California Santa Barbara, Materials Department, University of California, Santa Barbara, Materials Engineering, University of California, Santa Barbara, University of California Santa Barbara, Materials Engineering, Departments of Electrical and Computer Engineering and Materials, University of California, Santa Barbara

  • Leo P Kouwenhoven

    Microsoft Station Q at Delft University of Technology, Microsoft Quantum Delft, Qutech, Delft University of Technology, QuTech, Delft University of Technology, Station Q Delft, Microsoft, Microsoft Station Q Delft, Microsoft Station-Q at Delft University of Technology, Microsoft Station Q Delft, Delft University of Technology