Role of electron-electron and electron-phonon interaction effects in the optical conductivity of ${\mathrm{VO}}_{2}$

Role of electron-electron and electron-phonon interaction effects in the optical conductivity of ${VO}_{2}$

K. Okazaki, S. Sugai, Y. Muraoka, and Z. Hiroi

Phys. Rev. B 73, 165116 – Published 17 April 2006

Abstract

We have investigated the charge dynamics of ${VO}_{2}$ 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.