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VO2: a two-fluid incoherent metal?

M. S. Laad·L. Craco·E. Müller-Hartmann
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Abstract

We present {\it ab initio} LDA+DMFT results for the many-particle density of states of $VO_{2}$ on the metallic side of the strongly first-order ($T$-driven) insulator-metal transition. In strong contrast to LDA predictions, there is {\it no} remnant of even correlated Fermi liquid behavior in the correlated metal. Excellent quantitative agreement with published photoemission and X-ray absorption experiments is found in the metallic phase. We argue that the absence of FL-quasiparticles provides a natural explanation for the bad-metallic transport for $T > 340 K$. Based on this agreement, we propose that the I-M transition in $VO_{2}$ is an orbital-selective Mott transition, and point out the relevance of orbital resolved one-electron and optical spectroscopy to resolve this outstanding issue.

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M. S. Laad, L. Craco, E. Müller-Hartmann. 2004-09-01. VO2: a two-fluid incoherent metal?. https://doi.org/10.1209/epl%2Fi2004-10430-0

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