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arXiv · 0709.3240

Spin-texture and magneto-roton excitations at nu=1/3

Javier G. Groshaus·Irene Dujovne·Yann Gallais·Cyrus F. Hirjibehedin·Aron Pinczuk·Yan-Wen Tan·Horst Stormer·Brian S. Dennis·Loren N. Pfeiffer·Ken W. West
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Abstract

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.

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Javier G. Groshaus, Irene Dujovne, Yann Gallais, Cyrus F. Hirjibehedin, Aron Pinczuk, Yan-Wen Tan, Horst Stormer, Brian S. Dennis, Loren N. Pfeiffer, Ken W. West. 2007-09-20. Spin-texture and magneto-roton excitations at nu=1/3. https://doi.org/10.1103/physrevlett.100.046804

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