We present magnetotransport measurements performed on two-dimensional hole gases embedded in carbon doped p-type GaAs/AlGaAs heterostructures grown on [001] oriented substrates. A pronounced beating pattern in the Shubnikov-de Haas oscillations proves the presence of strong spin-orbit interaction in the device under study. We estimate the effective masses of spin-orbit split subbands by measuring the temperature dependence of the Shubnikov-de Haas oscillations at different hole densities. While the lighter heavy-hole effective mass is not energy dependent, the heavier heavy-hole effective mass has a prominent energy dependence, indicating a strong spin-orbit induced non parabolicity of the valence band. The measured effective masses show qualitative agreement with self-consistent numerical calculations.
@article{arxiv.1310.7638,
title = {Spin-orbit splitting and effective masses in p-type GaAs two-dimensional hole gases},
author = {Fabrizio Nichele and Atindra Nath Pal and Roland Winkler and Christian Gerl and Werner Wegscheider and Thomas Ihn and Klaus Ensslin},
journal= {arXiv preprint arXiv:1310.7638},
year = {2014}
}