Towards tunable quantum criticality in InAs quantum wells: Quantum point contacts and other quantum circuit building blocks

ORAL

Abstract

The intrinsic surface Fermi level pinning in InAs allows for submicron, non-annealed Ohmic contacts—in contrast to GaAs/AlGaAs—providing an avenue for miniaturizing charge Kondo devices recently studied in GaAs[1, 2]. We demonstrate quantum point contacts in a high-mobility (106 cm2/Vs) buried InAs quantum well grown on a lattice-mismatched InP substrate. We additionally report on the measured g-factors, observing a many-body exchange enhancement of the out-of-plane g-factor. Despite the substrate-induced strain which is expected to produce dislocations, these gate-defined QPCs are of remarkable cleanliness and stability compared to previous demonstrations in similar heterostructures, and they offer exciting potential as building blocks for electron quantum optics and quantum simulation in InAs-based platforms.

[1] Iftikhar, Z. et al. Tunable quantum criticality and super-ballistic transport in a “charge” Kondo circuit. Science 360, 1315–1320 (2018).

[2] Pouse, W. et al. Exotic quantum critical point in a two-site charge Kondo circuit. arXiv:2108.12691 (2021).

*This work is supported by the Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract DE-AC02-76SF00515.

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Presenters

  • Connie L Hsueh

    • Stanford University
    • Stanford Univ

Authors

  • Connie L Hsueh

    • Stanford University
    • Stanford Univ

  • Praveen Sriram

    • Stanford University

  • Tiantian Wang

    • Purdue University

  • Candice Thomas

    • 1. Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907. 2.Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907
    • Purdue University

  • Marc A Kastner

    • Stanford Univ
    • Stanford University

  • Geoff Gardner

    • Purdue University

  • Michael J Manfra

    • Department of Physics and Astronomy, Birck Nanotechnology Center, and Microsoft Quantum Lab Purdue, Purdue University
    • Purdue University
    • Purdue University, West Lafayette, Indiana 47907, USA

  • David Goldhaber-Gordon

    • Stanford University
    • Stanford Univ