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arXiv · 0709.0541

Soft Spin Wave Near nu=1: Evidence for a Magnetic Instability in Skyrmion Systems

Y. Gallais·J. Yan·A. Pinczuk·L. N. Pfeiffer·K. W. West
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Abstract

The ground state of the two dimensional electron gas near $ν$=1 is investigated by inelastic light scattering measurements carried down to very low temperatures. Away from $ν$=1, the ferromagnetic spin wave collapses and a new low-energy spin wave emerges below the Zeeman gap. The emergent spin wave shows soft behavior as its energy increases with temperature and reaches the Zeeman energy for temperatures above 2 K. The observed softening indicates an instability of the two dimensional electron gas towards a magnetic order that breaks spin rotational symmetry. We discuss our findings in light of the possible existence of a Skyrme crystal.

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Y. Gallais, J. Yan, A. Pinczuk, L. N. Pfeiffer, K. W. West. 2008-02-22. Soft Spin Wave Near nu=1: Evidence for a Magnetic Instability in Skyrmion Systems. https://doi.org/10.1103/physrevlett.100.086806

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