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Evidence of a pressure-induced metallization process in monoclinic VO$_2$

E. Arcangeletti·L. Baldassarre·D. Di Castro·S. Lupi·L. Malavasi·C. Marini·A. Perucchi·P. Postorino
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Abstract

Raman and combined trasmission and reflectivity mid infrared measurements have been carried out on monoclinic VO$_2$ at room temperature over the 0-19 GPa and 0-14 GPa pressure ranges, respectively. The pressure dependence obtained for both lattice dynamics and optical gap shows a remarkable stability of the system up to P*$\sim$10 GPa. Evidence of subtle modifications of V ion arrangements within the monoclinic lattice together with the onset of a metallization process via band gap filling are observed for P$>$P*. Differently from ambient pressure, where the VO$_2$ metal phase is found only in conjunction with the rutile structure above 340 K, a new room temperature metallic phase coupled to a monoclinic structure appears accessible in the high pressure regime, thus opening to new important queries on the physics of VO$_2$.

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E. Arcangeletti, L. Baldassarre, D. Di Castro, S. Lupi, L. Malavasi, C. Marini, A. Perucchi, P. Postorino. 2006-11-10. Evidence of a pressure-induced metallization process in monoclinic VO$_2$. https://doi.org/10.1103/physrevlett.98.196406

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