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arXiv · 1104.1346

Extended Drude model and role of interband transitions in the mid-infrared spectra of pnictides

L. Benfatto·E. Cappelluti·L. Ortenzi·L. Boeri
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Abstract

We analyze the outcomes of an extended-Drude-model approach to the optical spectra of pnictides, where the multiband nature of the electronic excitations requires a careful analysis of the role of interband processes in the optical conductivity.Through a direct comparison between model calculations of the intraband optical spectra and experimental data, we show that interband transitions,whose relevance is shown by first-principle calculations,give a non negligible contribution already in the infrared region. This leads to a substantial failure of the extended-Drude-model analysis on the measured optical data without subtraction of interband contributions.

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L. Benfatto, E. Cappelluti, L. Ortenzi, L. Boeri. 2011-04-11. Extended Drude model and role of interband transitions in the mid-infrared spectra of pnictides. https://doi.org/10.1103/physrevb.83.224514

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