We imaged the transport of current-induced spin coherence in a two-dimensional electron gas confined in a triple quantum well. Nonlocal Kerr rotation measurements, based on the optical resonant amplification of the electrically-induced polarization, revealed a large spatial variation of the electron g factor and the efficient generation of a current controlled spin-orbit field in a macroscopic Hall bar device. We observed coherence times in the nanoseconds range transported beyond half-millimeter distances in a direction transverse to the applied electric field. The measured long spin transport length can be explained by two material properties: large mean free path for charge diffusion in clean systems and enhanced spin-orbit coefficients in the triple well.
@article{arxiv.1605.06854,
title = {Macroscopic transverse drift of long current-induced spin coherence in two-dimensional electron gases},
author = {F. G. G. Hernandez and S. Ullah and G. J. Ferreira and N. M. Kawahala and G. M. Gusev and A. K. Bakarov},
journal= {arXiv preprint arXiv:1605.06854},
year = {2016}
}