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The low-energy ARPES and heat capacity of Na$_{0.3}$CoO$_2$: A DMFT study

C. A. Marianetti·K. Haule·O. Parcollet
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Abstract

The cobaltates have demonstrated a wide variety complex behavior. The Na rich region of the phase diagram displays various degrees of anomalous behavior, such as Curie-Weiss behavior near a band insulator\cite{Foo:2004}, charge disproportionation\cite{Mukhamedshin:2005}, and non-Fermi-liquid behavior in the resistivity\cite{Foo:2004}. Alternatively, the Na poor region of the phase diagram appears to be a Fermi-liquid. The magnetic susceptibility displays Pauli behavior, the resistivity is roughly quadratic at low temperatures\cite{Foo:2004}, and the system appears to be homogeneous\cite{Mukhamedshin:2005}. Therefore, the Na poor region of the phase diagram seems like a natural starting point to attempt to explain the ARPES experiments and heat capacity measurements from a quantitative standpoint.

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C. A. Marianetti, K. Haule, O. Parcollet. 2006-12-22. The low-energy ARPES and heat capacity of Na$_{0.3}$CoO$_2$: A DMFT study. https://doi.org/10.1103/physrevlett.99.246404

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