Anomalous semiconducting behavior on VO2 under high pressure

Abstract

High-pressure electrical transport properties of VO₂ have been investigated by in situ resistivity, Hall-effect, and temperature dependence of resistivity measurements. The electrical transport parameters including resistivity, Hall coefficient, carrier concentration, and mobility varies significantly around 10.4 GPa, which can be attributed to the isostructural phase transition of VO₂. Temperature dependence of resistivity indicates that the phase transition is a semiconductor-to-semiconductor transformation, not the pressure-induced metallization as previously reported by Raman and IR experiment observations. The dramatic increase of activation energy at 10.4 GPa indicates an increasingly insulating behavior of VO₂ accompanied with the isostructural phase transition. The electrical transport properties, especially the carries transportation under compression open up a new possible basis for optimizing the performance of VO₂ based applications under ambient or extreme conditions.