Strain Engineering of Metal Insulator Transition in VO2

Abstract

Vanadium dioxide (VO2) has been a focus of interest for the past few decades for its reversible metal insulator transition (MIT) accompanied by structural transition at 68 °C along with abrupt changes in the electrical, optical and mechanical properties. VO2 has proven to be an excellent smart material for applications such as actuators, thermochromic windows, strain sensors, cantilevers, and memristor devices. The MIT in VO2 is highly susceptible to heat, strain, light and electric field. Strain introduced by an external load, substrate and chemical doping are a few routes to manipulate the transition temperature for the monoclinic to tetragonal phase change. This book chapter presents an overview phase transition mechanisms and methods to tune the MIT temperature in functional oxides by taking VO2 as a model system. The phase transition mechanism is correlated with electron-lattice and electron–electron interaction which is explained by Peierls and Mott-like transition. Tuning of MIT temperature by different stimuli such as applied strain like bending, lattice mismatch strain and chemical doping is discussed along with few relevant applications.