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arXiv · 0804.3940

GdI_2: A New Ferromagnetic Excitonic Solid?

A. Taraphder·M. S. Laad·L. Craco·A. N. Yaresko
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Abstract

The two-dimensional, colossal magnetoresistive system GdI_2 develops an unusual metallic state below its ferromagnetic transition and becomes insulating at low temperatures. It is argued that this geometrically frustrated, correlated poor metal is a possible candidate for a ferromagnetic excitonic liquid. The renormalized Fermi surface supports a further breaking of symmetry to a charge ordered, excitonic solid ground state at lower temperatures via order by disorder mechanism. Several experimental predictions are made to investigate this unique orbitally correlated ground state.

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A. Taraphder, M. S. Laad, L. Craco, A. N. Yaresko. 2008-08-13. GdI_2: A New Ferromagnetic Excitonic Solid?. https://doi.org/10.1103/physrevlett.101.136410

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