VO2 under hydrostatic pressure: Isostructural phase transition close to a critical endpoint
The authors unveil here new findings in the realm of phase transitions in VO2 single crystals, all achieved under hydrostatic pressure conditions. They provide experimental results, exploiting the observation of soft phonons through Raman spectroscopy and high-quality structural refinements. These findings offer a fresh perspective on phase diagrams, including a precise description of the M1-M′1 isostructural transition occurring at 14 GPa. The study also reveals that isothermal compression at 298 K drives a thrilling journey close to the critical point. The authors present the first Raman signature of the elusive metallic X-phase, observed at pressures exceeding 32 GPa
P. Bouvier, L. Bussmann, D. Machon, I. Breslavetz, G. Garbarino, P. Strobel, and V. Dmitriev