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Role of electron-electron and electron-phonon interaction effect in the optical conductivity of VO2

K. Okazaki·S. Sugai·Y. Muraoka·Z. Hiroi
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Abstract

We have investigated the charge dynamics of VO2 by optical reflectivity measurements. Optical conductivity clearly shows a metal-insulator transition. In the metallic phase, a broad Drude-like structure is observed. On the other hand, in the insulating phase, a broad peak structure around 1.3 eV is observed. It is found that this broad structure observed in the insulating phase shows a temperature dependence. We attribute this to the electron-phonon interaction as in the photoemission spectra.

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K. Okazaki, S. Sugai, Y. Muraoka, Z. Hiroi. 2006-03-13. Role of electron-electron and electron-phonon interaction effect in the optical conductivity of VO2. https://doi.org/10.1103/physrevb.73.165116

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