Soft spin wave near nu=1: evidence for a magnetic instability in Skyrmion systems.
نویسندگان
چکیده
The ground state of the two-dimensional electron gas near nu=1 is investigated by inelastic light scattering measurements carried down to very low temperatures. Away from nu=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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عنوان ژورنال:
- Physical review letters
دوره 100 8 شماره
صفحات -
تاریخ انتشار 2008