Kinks in the Electronic Specific Heat

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 T3 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.