Effect of ultraviolet irradiation on electrical resistance and phase transition characteristics of thin film vanadium oxide

Metal-insulator transitions in strongly correlated oxides such as vanadium oxide (VO2) are of great scientific and technological interest. Due to the presence of multiple oxidation states, synthesis of high-quality VO2 films on substrates with the desired phase transition characteristics such as large jumps in phase transition resistance is a challenge. We show that the resistance ratio across the metal-insulator transition as well as the resistance of thin film VO2 can be modulated at relatively low temperatures by the use of ultraviolet irradiation. The enhanced oxygen incorporation due to creation of excited oxygen species enables controllably tunable stoichiometry