We report on the observation of a spin texture in a cold exciton gas in a GaAs/AlGaAs coupled quantum well structure. The spin texture is observed around the exciton rings. The observed phenomena include: a ring of linear polarization, a vortex of linear polarization with polarization perpendicular to the radial direction, an anisotropy in the exciton flux, a skew of the exciton fluxes in orthogonal circular polarizations and a corresponding four-leaf pattern of circular polarization, a periodic spin texture, and extended exciton coherence in the region of the polarization vortex. The data indicate a transport regime where the spin polarization is locked to the direction of particle propagation and scattering is suppressed.
@article{arxiv.1103.0321,
title = {Spin Texture in a Cold Exciton Gas},
author = {A. A. High and A. T. Hammack and J. R. Leonard and Sen Yang and L. V. Butov and T. Ostatnicky and A. V. Kavokin and A. C. Gossard},
journal= {arXiv preprint arXiv:1103.0321},
year = {2013}
}