Neutral spin texture ST excitations at nu=1/3 are directly observed for the first time by resonant inelastic light scattering. They are determined to involve two simultaneous spin- flips. At low magnetic fields, the ST energy is below that of the magneto-roton minimum. With increasing in-plane magnetic field these modes energies cross at a critical ratio of the Zeeman and Coulomb energies of eta_c=0.020 +- 0.001. Surprisingly, the intensity of the ST mode grows with temperature in the range in which the magneto-roton modes collapse. The temperature dependence is interpreted in terms of a competition between coexisting phases supporting different excitations. We consider the role of the ST excitations in activated transport at nu=1/3.
@article{arxiv.0709.3240,
title = {Spin-texture and magneto-roton excitations at nu=1/3},
author = {Javier G. Groshaus and Irene Dujovne and Yann Gallais and Cyrus F. Hirjibehedin and Aron Pinczuk and Yan-Wen Tan and Horst Stormer and Brian S. Dennis and Loren N. Pfeiffer and Ken W. West},
journal= {arXiv preprint arXiv:0709.3240},
year = {2009}
}