Strain Effects on Rashba Spin‐Orbit Coupling of 2D Hole Gases in GeSn/Ge Heterostructures
Chia‐Tse Tai, Po‐Yuan Chiu, Chia-You Liu, Hsiang‐Shun Kao, Charles Thomas Harris, Tzu‐Ming Lu, Chi‐Ti Hsieh, Shu‐Wei Chang, Jiun‐Yun Li
Abstract
is given. Both the Shubnikov-de Haas oscillations and integer quantum Hall effect are observed, indicating high sample quality. The Rashba spin-orbit coupling (SOC) is investigated via magneto-transport. Further, a transition from weak localization to weak anti-localization is observed, which shows the tunability of the SOC strength by gating. The magneto-transport data are fitted to the Hikami-Larkin-Nagaoka formula. The phase-coherence and spin-relaxation times, as well as spin-splitting energy and Rashba coefficient of the k-cubic term, are extracted. The analysis reveals that the effects of strain and confinement potential at a high fraction of Sn suppress the Rashba SOC caused by the GeSn/Ge heterostructures.