Strong and Tunable Spin-Orbit Coupling in a Two-Dimensional Hole Gas in Ionic-Liquid Gated Diamond Devices
Golrokh Akhgar, Oleh Klochan, Laurens H Willems van Beveren, Mark T Edmonds, Florian Maier, Benjamin J Spencer, Jeffrey C McCallum, Lothar Ley, Alex R Hamilton, Christopher I Pakes
NANO LETTERS | AMER CHEMICAL SOC | Published : 2016
Hydrogen-terminated diamond possesses due to transfer doping a quasi-two-dimensional (2D) hole accumulation layer at the surface with a strong, Rashba-type spin-orbit coupling that arises from the highly asymmetric confinement potential. By modulating the hole concentration and thus the potential using an electrostatic gate with an ionic-liquid dielectric architecture the spin-orbit splitting can be tuned from 4.6-24.5 meV with a concurrent spin relaxation length of 33-16 nm and hole sheet densities of up to 7.23 × 10(13) cm(-2). This demonstrates a spin-orbit interaction of unprecedented strength and tunability for a 2D hole system at the surface of a wide band gap semiconductor. With a spi..View full abstract
Awarded by Australian Research Council
This work was supported by the Australian Research Council under the Discovery Project (DP150101673) and Discovery Early Career Research Awards (DE140100775) schemes. This work was performed in part at the University of Sydney: Bandwidth Foundry International, part of the OptoFab node of the Australian National Fabrication Facilities.