Soft spin wave near nu=1: evidence for a magnetic instability in Skyrmion systems.
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.
Gallais
Yann
Y
Departments of Physics and of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA. yann.gallais@univ-paris-diderot.fr
Yan
Jun
J
Pinczuk
Aron
A
Pfeiffer
Loren N
LN
West
Ken W
KW