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arXiv · 0712.3723

Kinks in the electronic specific heat

A. Toschi·M. Capone·C. Castellani·K. Held
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Abstract

We find that the heat capacity of a strongly correlated metal presents striking changes with respect to Landau Fermi liquid theory. In contrast with normal metals, where the electronic specific heat is linear at low temperature (with a T^3 term as a leading correction), a dynamical mean-field study of the correlated Hubbard model reveals a clear kink in the temperature dependence, marking a rapid change from a low-temperature linear behavior and a second linear regime with a reduced slope. Experiments on LiV2O4 support our findings, implying that correlated materials are more resistive to cooling at low T than expected from the intermediate temperature behavior.

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A. Toschi, M. Capone, C. Castellani, K. Held. 2009-07-21. Kinks in the electronic specific heat. https://doi.org/10.1103/physrevlett.102.076402

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