The metal–insulator phase change in vanadium dioxide and its applications

Abstract

Vanadium dioxide is an unusual material that undergoes a first-order Metal–Insulator Transition (MIT) at 340 K, attracting considerable interest for its intrinsic properties and its potential applications. However, the nature of MIT has not been fully determined. Variants of density functional theory (DFT) have been widely used to study the MIT in pure and doped VO2. A full description of MIT is complicated by several related factors such as V–V dimerization, magnetic properties, and spin correlations. Each of these requires careful attention. In this Perspective, we explain why DFT fails, introduce a spin-pairing model of MIT, and propose a new way to estimate the transition temperature. We then use the method to study the doping and alloying process. Finally, we give an overview of some applications of MIT. This work aims to provide insight into and stimulate more research studies in this promising field.