Anisotropic Zeeman shift in p-type GaAs quantum point contacts

¹ Solid State Physics Laboratory, ETH Zurich - 8093 Zurich, Switzerland
² Electronics/Metrology/Reliability Laboratory, EMPA - 8600 Duebendorf, Switzerland
³ School of Chemical and Physical Sciences and MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington - Wellington 6140, New Zealand
⁴ Angewandte Festkörperphysik, Ruhr- Universität Bochum - 44780 Bochum, Germany, EU

^{(a) (b) (c)} Present address: Department of Physics and Astronomy, University of British Columbia - Vancouver, B.C., Canada V6T 1Z1Present address: Department of Physics, Budapest University of Technology and Economics - 1111 Budapest, Hungary, EUPresent address: University Paderborn, Department Physik - Warburger Stra�e 100, 33098 Paderborn, Germany, EU; komijani@phas.ubc.ca

Received: 8 February 2013
Accepted: 15 April 2013

Abstract

Low-temperature electrical conductance spectroscopy measurements of quantum point contacts implemented in p-type GaAs/AlGaAs heterostructures are used to study the Zeeman splitting of 1D subbands for both in-plane and out-of-plane magnetic field orientations. The resulting in-plane g-factors agree qualitatively with those of previous experiments on quantum wires while the quantitative differences can be understood in terms of the enhanced quasi-1D confinement anisotropy. The influence of confinement potential on the anisotropy is discussed and an estimate for the out-of-plane g-factor is obtained which, in contrast to previous experiments, is close to the theoretical prediction.