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arXiv · 1008.0942

Preformed excitonic liquid route to a charge density wave in 2H-TaSe$_2$

A. Taraphder·S. Koley·N. S. Vidhyadhiraja·M. S. Laad
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Abstract

Recent experiments on 2H-TaSe$_2$ contradict the long-held view of the charge density wave arising from a nested band structure. An intrinsically strong coupling view, involving a charge density wave state arising as a Bose condensation of preformed excitons emerges as an attractive, albeit scantily investigated alternative. Using local density approximation plus multiorbital dynamic mean-field theory, we show that this scenario agrees with a variety of normal state data for 2H-TaSe$_{2}$. Based thereupon, the ordered states in a subset of dichalcogenides should be viewed as instabilities of a correlated, preformed excitonic liquid.

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A. Taraphder, S. Koley, N. S. Vidhyadhiraja, M. S. Laad. 2011-06-14. Preformed excitonic liquid route to a charge density wave in 2H-TaSe$_2$. https://doi.org/10.1103/physrevlett.106.236405

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