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  • Letter
  • Open Access

Imaging signatures of the local density of states in an electronic cavity

Carolin Gold1,*, Beat A. Bräm1, Michael S. Ferguson2, Tobias Krähenmann1, Andrea Hofmann1, Richard Steinacher1, Keith R. Fratus3,4, Christian Reichl1, Werner Wegscheider1 et al.

Dietmar Weinmann3, Klaus Ensslin1,5, and Thomas Ihn1,5

  • 1Solid State Laboratory, ETH Zurich, 8093 Zurich, Switzerland
  • 2Institute for Theoretical Physics, ETH Zurich, 8093 Zurich, Switzerland
  • 3Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, F-67000 Strasbourg, France
  • 4HQS Quantum Simulations, Haid-und-Neu-Str. 7, 76131 Karlsruhe, Germany
  • 5Quantum Center, ETH Zurich, CH-8093 Zurich, Switzerland

  • *cgold@phys.ethz.ch
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Phys. Rev. Research 3, L032005 – Published 6 July, 2021

DOI: https://doi.org/10.1103/PhysRevResearch.3.L032005

Abstract

We use scanning gate microscopy to study electron transport through an open, gate-defined resonator in a Ga(Al)As heterostructure. Raster-scanning the voltage-biased metallic tip above the resonator, we observe distinct conductance modulations as a function of the tip position and voltage. Quantum-mechanical simulations reproduce these conductance modulations and reveal their relation to the partial local density of states in the resonator. Our measurements illustrate the current frontier between possibilities and limitations in imaging the local density of states in buried electron systems using scanning gate microscopy.

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Phys. Rev. Research 3, L032005– Published 6 July, 2021
  • Received 27 November 2020
  • Accepted 9 April 2021
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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