Strong and tunable spin-orbit coupling in a two-dimensional hole gas in ionic-liquid gated diamond devices Academic Article uri icon

abstract

  • 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 spin relaxation length that is experimentally accessible using existing nanofabrication techniques, this result suggests that hydrogen-terminated diamond has great potential for the study and application of spin transport phenomena.

authors

  • Akhgar, G
  • Klochan, O
  • van Beveren, LHW
  • Edmonds, MT
  • Maier, F
  • Spencer, BJ
  • McCallum, JC
  • Ley, L
  • Hamilton, AR
  • Pakes, CI

publication date

  • 2016