Edge State Wave-Functions probed by Tunneling Spectroscopy

ORAL

Abstract

Edge states have recently attracted a lot of attention due to their appearance at surfaces of topological materials and quantum Hall systems. Here we study quantum Hall edge states formed in a GaAs 2D electron gas using a tunnel-coupled quantum wire [1]. We use momentum-conserving tunneling spectroscopy to distinguish spatially overlapping states with different momenta. The tunneling conductance is proportional to the overlap between the edge state and the wire mode wave functions. Because of the varying shape of wire wave functions, their overlaps with edge states will also vary, resulting in a distinct sequence of tunneling conductance intensity patterns for different wire modes. We use self-consistent calculations to obtain the electrostatic potential at zero magnetic field and employ a Schrödinger solver to get the wave functions of the Landau level edge states and wire modes at a finite field. Conductance maps obtained using simulated wave functions agree very well with the measured data, thus confirming the calculated wave functions.

[1] “Evolution of the quantum Hall bulk spectrum into chiral edge states”, T. Patlatiuk, C. P. Scheller et al., Nature Communications 9, 3692, (2018)

*Supported by Swiss NSF, NCCR QSIT, SNI, European Microkelvin Platform (EMP), NSF, EPiQS, MRSEC.

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Presenters

  • Taras Patlatiuk

    • University of Basel
    • Department of Physics, Univ of Basel

Authors

  • Taras Patlatiuk

    • University of Basel
    • Department of Physics, Univ of Basel

  • Christian Scheller

    • University of Basel
    • Department of Physics, Univ of Basel
    • University of Basel, Department of Physics

  • Daniel M Hill

    • Univ of California - Los Angeles

  • Yaroslav Tserkovnyak

    • Univ of California - Los Angeles
    • Physics, UCLA
    • Physics, Univ of California - Los Angeles
    • Department of Physics and Astronomy, University of California, Los Angeles
    • Physics, University of California, Los Angeles
    • University of California, Los Angeles

  • Amir Yacoby

    • Harvard University
    • Harvard Univ
    • Physics, Harvard University
    • Department of Physics, Harvard University & School of Engineering and Applied Sciences, Harvard University

  • Loren Pfeiffer

    • Electrical Engineering, Princeton University
    • Princeton University
    • Princeton Univ
    • Department of Electrical Engineering, Princeton University
    • PRISM, Princeton University
    • Physics, Princeton University
    • Electrical Engineering, Princeton

  • Kenneth West

    • Electrical Engineering, Princeton University
    • Princeton University
    • Princeton Univ
    • Department of Electrical Engineering, Princeton University
    • PRISM, Princeton University
    • Physics, University of Pittsburgh
    • Electrical Engineering, Princeton

  • Dominik Zumbuhl

    • University of Basel
    • Department of Physics, Univ of Basel
    • University of Basel, Department of Physics
    • Department of Physics, University of Basel
    • Physics, University of Basel