We have used gated GaAs/AlGaAs heterostructures to explore nonlinear transport between spin-resolved Landau level (LL) edge states over a submicron region of two-dimensional electron gas (2DEG). The current I flowing from one edge state to the other as a function of the voltage V between them shows diode-like behavior---a rapid increase in I above a well-defined threshold V_t under forward bias, and a slower increase in I under reverse bias. In these measurements, a pronounced influence of a current-induced nuclear spin polarization on the spin splitting is observed, and supported by a series of NMR experiments. We conclude that the hyperfine interaction plays an important role in determining the electronic properties at the edge of a 2DEG.
@article{arxiv.cond-mat/9701039,
title = {Dynamic nuclear polarization at the edge of a two-dimensional electron gas},
author = {David C. Dixon and Keith R. Wald and Paul L. McEuen and M. R. Melloch},
journal= {arXiv preprint arXiv:cond-mat/9701039},
year = {2009}
}
Comments
8 pages RevTeX, 7 figures (GIF); submitted to Phys. Rev. B