Quantized conductance doubling in gate tunable hybrid superconducting-semiconducting quantum wire arrays

ORAL

Abstract

In gated hybrid superconductor-semiconductor junctions made from two-dimensional (2D) semiconducting electron gas systems, the electrostatic field effect produced by the split gate voltages enables the realisation of one-dimensional (1D) quantum wires (electron waveguides). In this work, we experimentally demonstrate large-scale on-chip integration of gate voltage tunable hybrid superconducting-semiconducting field-effect switch arrays on the InGaAs quantum wells platform. Each hybrid junction in the chip can be controlled and addressed through its corresponding source-drain as well as two global split gate contact pads that allow switching between their (super)conducting and insulating states. We systematically investigate the quantum transport, switching voltage (on/off) states, quantum yield, and reproducibility of quantized conductance in several field-effect devices at cryogenic temperatures. We observe quantized conductance doubling in gated field effect junctions with a single interface and study their behaviour as a function of temperature and magnetic fields.

Presenters

  • Kaveh Delfanazari

    University of Glasgow

Authors

  • Kaveh Delfanazari

    University of Glasgow

  • Jiahui Li

    University of Cambridge

  • YUSHENG XIONG

    University of Glasgow

  • Peng Ma

    University of Cambridge

  • Reuben Puddy

    University of Cambridge

  • Ian Farrer

    University of Sheffield, University of Sheffield, United Kingdom, Sheffield University

  • Sachio Komori

    University of Nagoya

  • Jason Robinson

    University of Cambridge

  • Llorenç Serra

    IFISC & University of the Balearic Islands, Institute of Interdisciplinary Physics and Complex Systems IFISC (CSIC-UIB) and Physics Department, University of the Balearic Islands, Palma, E-07122, Spain

  • David A Ritchie

    Univ of Cambridge, University of Cambridge

  • Michael J Kelly

    Univ of Cambridge

  • Hannah Joyce

    Univ of Cambridge, University of Cambridge

  • Charles G Smith

    Univ of Cambridge