Spin-orbit interactions and the origins of the huge anisotropy of in-plane g-factors in 1D holes in GaAs quantum point contacts

ORAL

Abstract

Holes in 2D and 1D GaAs systems have a very strong spin-orbit interaction due to the J=3/2 nature of the heavy holes. It has been known for over a decade that the in-plane hole g factors in GaAs quantum point contacts has a very strong dependence on the orientation of the magnetic field with respect to the electric current. However, despite numerous observations of this effect by multiple groups, the origins of this anistropy have remained a mystery. Here we resolve this problem. We present systematic experimental studies to disentangle different mechanisms contributing to the g-factor anisotropy. Theoretical analysis shows that there is a new mechanism for the anisotropy related to the existence of an additional B+k-4σ+ effective Zeeman interaction for holes, which is kinematically different from the standard Zeeman term B-k-2σ+ considered in previous works.

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Presenters

  • Alex Hamilton

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

Authors

  • Alex Hamilton

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

  • Ashwin Srinivasan

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

  • Dima Miserev

    Univ of New South Wales

  • O. Tkachenko

    Rzhanov Institute of Semiconductor Physics of SB RAS

  • V. A.

    Rzhanov Institute of Semiconductor Physics of SB RAS

  • I. Farrer

    Department of Electronic and Electrical Engineering, University of Sheffield, University of Sheffield

  • David Ritchie

    Cavendish Laboratory, University of Cambridge, University of Cambridge, Univ of Cambridge, Cavendish Laboratory, Cambridge University

  • Oleg Sushkov

    University of New South Wales, Univ of New South Wales