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On the heavy-fermion behavior of the pyrochlore transition-metal oxide $LiV_{2}O_{4}$

M. S. Laad·L. Craco·E. Müller-Hartmann
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Abstract

Motivated by the heavy fermion Fermi liquid (HFFL) features observed at low-$T$ in the pyrochlore $LiV_{2}O_{4}$, we consider a material-specific model that includes aspects of the local quantum chemistry, the geometrically frustrated lattice structure, and strong correlations in a {\it single} approach. In particular, we show how geometrical frustration (GF) gives rise to a crossover scale, $T^{*}<<J$, the intersite (AF) exchange, below which the metallic system shows HFFL features. Our scenario is a specific realization of the importance of GF effects in driving HFFL behavior in $LiV_{2}O_{4}$, and provides a natural understanding of various puzzling features observed experimentally.

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M. S. Laad, L. Craco, E. Müller-Hartmann. 2002-02-28. On the heavy-fermion behavior of the pyrochlore transition-metal oxide $LiV_{2}O_{4}$. https://doi.org/10.1103/physrevb.67.033105

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