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arXiv · 0810.4744

Macroscopic signature of protected spins in a dense frustrated magnet

S. Ghosh·T. F. Rosenbaum·G. Aeppli
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Abstract

The inability of systems of interacting objects to satisfy all constraints simultaneously leads to frustration. A particularly important consequence of frustration is the ability to access certain protected parts of a system without disturbing the others. For magnets such "protectorates" have been inferred from theory and from neutron scattering, but their practical consequences have been unclear. We show that a magnetic analogue of optical hole-burning can address these protected spin clusters in a well-known, geometrically frustrated Heisenberg system, gadolinium gallium garnet. Our measurements additionally provide a resolution of a famous discrepancy between the bulk magnetometry and neutron diffraction results for this magnetic compound.

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S. Ghosh, T. F. Rosenbaum, G. Aeppli. 2008-10-27. Macroscopic signature of protected spins in a dense frustrated magnet. https://doi.org/10.1103/physrevlett.101.157205

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