The spin-orbit interaction (SOI) of the two-dimensional hole gas in the inversion symmetric semiconductor Ge is studied in a strained-Ge/SiGe quantum well structure. We observed weak anti-localization (WAL) in the magnetoconductivity measurement, revealing that the WAL feature can be fully described by the k-cubic Rashba SOI theory. Furthermore, we demonstrated electric field control of the Rashba SOI. Our findings reveal that the heavy hole (HH) in strained-Ge is a purely cubic-Rashba-system, which is consistent with the spin angular momentum mj = +-3/2 nature of the HH wave function.
@article{arxiv.1408.1148,
title = {Cubic Rashba spin-orbit interaction of two-dimensional hole gas in strained-Ge/SiGe quantum well},
author = {Rai Moriya and Kentarou Sawano and Yusuke Hoshi and Satoru Masubuchi and Yasuhiro Shiraki and Andreas Wild and Christian Neumann and Gerhard Abstreiter and Dominique Bougeard and Takaaki Koga and Tomoki Machida},
journal= {arXiv preprint arXiv:1408.1148},
year = {2015}
}