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arXiv:cond-mat/0502528 · Physical Review Letters

Temperature Dependence of the Optical Spectral Weight in the Cuprates: Role of Electron Correlations

A. Toschi, Massimo Capone, Michele Ortolani, P. Calvani, S. Lupi, Claudio Castellani

Published Aug 24, 2005• 67 citations
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Abstract

We compare calculations based on the dynamical mean-field theory of the Hubbard model with the infrared spectral weight $W(\ensuremath{\Omega},T)$ of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ and other cuprates. Without using fitting parameters we show that most of the anomalies found in $W(\ensuremath{\Omega},T)$ with respect to normal metals, including the existence of two different energy scales for the doping and the $T$ dependence of $W(\ensuremath{\Omega},T)$, can be ascribed to strong correlation effects.

DOI
10.1103/physrevlett.95.097002

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