Raman and combined trasmission and reflectivity mid infrared measurements have been carried out on monoclinic VO2 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*∼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 VO2 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 VO2.
@article{arxiv.cond-mat/0611281,
title = {Evidence of a pressure-induced metallization process in monoclinic VO$_2$},
author = {E. Arcangeletti and L. Baldassarre and D. Di Castro and S. Lupi and L. Malavasi and C. Marini and A. Perucchi and P. Postorino},
journal= {arXiv preprint arXiv:cond-mat/0611281},
year = {2010}
}