In a system accommodating both surface and bulk conduction channels, a long-standing challenge is to extract weak Shubnikov-de Haas oscillation signal in the surface from a large background stemming from the bulk. Conventional methods to suppress the bulk conduction often involve doping, an intrusive approach, to reduce the bulk carrier density. Here we propose a geometric method, i.e. attaching a metal shunt to the indium arsenide epilayer, to redistribute current and thus enhance the oscillation-to-background ratio. This allows us, for the first time, to observe clear quantum oscillations and nonzero Berry's phase at the surface of indium arsenide. We also identify the existence of a Rashba type spin-orbit interaction, on the InAs surface, with a large coupling constant ~ 1 eVA. We anticipate wide applicability of this non-intrusive architecture in similar systems such as topological insulators.
@article{arxiv.1503.05833,
title = {Geometrically Enhanced Quantum Oscillatory Signal and Nonzero Berry's Phase in Indium Arsenide Surface},
author = {Jian Sun and Xuhui Wang and Sadamichi Maekawa and Aurelien Manchon and Jurgen Kosel},
journal= {arXiv preprint arXiv:1503.05833},
year = {2015}
}