High-critical-field superconducting heterostructures using anodic oxidation

ORAL

Abstract

In-situ growth of Al on top of shallow InAs 2DEG heterostructures gives close to perfect proximity effect [1-2]. The transparent super/semi interface combined with customizable 2DEG lithography hold promise to many interesting applications, e.g. topological quantum computation [3-4].
When the aluminum is chemically etched the underlying InAs is degraded by surface impurities. [2]
Instead of etching the aluminum, here we show that controllably oxidizing the Al through anodic oxidation (AO) gives up to a factor 2 increase in InAs mobility and Quantum Hall effect emerges before 3 Tesla.
We will also show how AO can be used to controllably thin down Al, thus increasing its superconducting properties [2,5-6], obtaining an in-plane critical field > 6 T and a perpendicular critical field > 3T on a mesoscopic structure.
Besides enhancing superconducting properties of established devices, this technique paves the way to new research topics, eg. Quantum Hall edge states proximitized by the surface Al with close to unity transparency.

[1] M. Kjærgaard et al. Nature commun. 12841
[2] J. Shabani et al. Phys. Rev. B 93, 159908
[3] F. Nichele et al. Phys. Rev. Lett. 119, 136803
[4] A. Fornieri et al. arXiv:1809.03037
[5] Y. Ivry et al. Phys. Rev. B 90, 214515
[6] P. Tedrow et al. Phys. Rev. B 25, 171

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Presenters

  • Asbjørn Drachmann

    Center for Quantum Devices, University of Copenhagen

Authors

  • Asbjørn Drachmann

    Center for Quantum Devices, University of Copenhagen

  • Henri J Suominen

    Center for Quantum Devices, University of Copenhagen

  • Alex R Hamilton

    School of Physics, University of New South Wales, Univ of New South Wales, University of New South Wales

  • Sergei Gronin

    Microsoft, Microsoft Quantum at Station Q Purdue, Purdue University, Department of Physics and Astronomy, Purdue University, Microsoft Quantum at Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA, Microsoft Station Q Purdue, Department of Physics and Astronomy and Station Q Purdue, Purdue University

  • Tian Wang

    Department of Physics and Astronomy and Station Q Purdue, Purdue University, Department of Physics and Astronomy, Purdue University, Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907 USA, Microsoft Station Q Purdue, Birck Nanotechnology Center, Purdue University

  • Geoffrey Gardner

    Department of Physics and Astronomy, Purdue University, Purdue University, Birck Nano Technology Center, Purdue University, Dept. of Physics, Purdue University, Department of Physics and Astronomy and Station Q Purdue, Purdue University, Department of Physics and Astronomy, Station Q Purdue, and Birck Nanotechnology Center, Purdue University

  • Candice Thomas

    Department of Physics and Astronomy and Station Q Purdue, Purdue University, Department of Physics and Astronomy, Purdue University, Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907 USA, Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA, Department of Physics and Astronomy, Station Q Purdue, and Birck Nanotechnology Center, Purdue University

  • Alexander Whiticar

    Center for Quantum Devices, University of Copenhagen, Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark, Center for Quantum Devices and Station Q Copenhagen, University of Copenhagen

  • Antonio Fornieri

    Center for Quantum Devices, University of Copenhagen, Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark, Center for Quantum Devices and Station Q Copenhagen, University of Copenhagen

  • Michael Manfra

    Purdue University, Microsoft, Department of Physics and Astronomy and Station Q Purdue, Purdue University, Department of Physics and Astronomy, Purdue University, Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907 USA, Microsoft Station Q Purdue, Physics and Astronomy, Purdue University, Department of Physics and Astronomy, School of Materials Engineering and School of Electrical and Computer Engineering, Purdue University, Station Q Purdue and Department of Physics and Astronomy, Purdue University, Dept. of Physics, Purdue University, Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA, Dept. of Physics and Astronomy, Purdue, Purdue University, Station Q Purdue, Department of Physics and Astronomy, Station Q Purdue, and Birck Nanotechnology Center, Purdue University

  • Charles M Marcus

    Microsoft, Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Center for Quantum Devices, University of Copenhagen, Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark, Center for Quantum Devices and Microsoft Quantum Lab--Copenhagen, Niels Bohr Institute, University of Copenhagen, Niels Bohr Institute, University of Copenhagen, Niels Bohr Institute, Center for Quantum Devices, Niels Bohr Institute, Center for Quantum Devices, Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Center for Quantum Devices and Microsoft Quantum Lab–Copenhagen, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark, University of Copenhagen, Center for Quantum Devices and Station Q Copenhagen, University of Copenhagen

  • Fabrizio Nichele

    Center for Quantum Devices, University of Copenhagen, IBM Research - Zurich, 8803 Rüschlikon, Switzerland, Center for Quantum Devices and Station Q Copenhagen, University of Copenhagen, IBM Zurich Research Laboratory