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Correlated metallic state of vanadium dioxide

M. M. Qazilbash·K. S. Burch·D. Whisler·D. Shrekenhamer·B. G. Chae·H. T. Kim·D. N. Basov
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Abstract

The metal-insulator transition and unconventional metallic transport in vanadium dioxide (VO$_2$) are investigated with a combination of spectroscopic ellipsometry and reflectance measurements. The data indicates that electronic correlations, not electron-phonon interactions, govern charge dynamics in the metallic state of VO$_2$. This study focuses on the frequency and temperature dependence of the conductivity in the regime of extremely short mean free path violating the Ioffe-Regel-Mott limit of metallic transport. The standard quasiparticle picture of charge conduction is found to be untenable in metallic VO$_2$.

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M. M. Qazilbash, K. S. Burch, D. Whisler, D. Shrekenhamer, B. G. Chae, H. T. Kim, D. N. Basov. 2006-11-28. Correlated metallic state of vanadium dioxide. https://doi.org/10.1103/physrevb.74.205118

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