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Temperature dependence of the optical spectral weight in the cuprates: Role of electron correlations

A. Toschi·M. Capone·M. Ortolani·P. Calvani·S. Lupi·C. Castellani
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Abstract

We compare calculations based on the Dynamical Mean-Field Theory of the Hubbard model with the infrared spectral weight $W(Ω,T)$ of La$_{2-x}$Sr$_x$CuO$_4$ and other cuprates. Without using fitting parameters we show that most of the anomalies found in $W(Ω,T)$ with respect to normal metals, including the existence of two different energy scales for the doping- and the $T$-dependence of $W(Ω,T)$, can be ascribed to strong correlation effects.

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A. Toschi, M. Capone, M. Ortolani, P. Calvani, S. Lupi, C. Castellani. 2005-09-21. Temperature dependence of the optical spectral weight in the cuprates: Role of electron correlations. https://doi.org/10.1103/physrevlett.95.097002

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