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.

*This work was funded by the ARC under the DP scheme.

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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