Volatile and non-volatile behavior of metal-insulator transition in VO2 through oxygen vacancies tunability for memory applications

Vanadium dioxide can be utilized as a Mott memory, where 0 and 1 states can be defined by insulator and metal states, respectively. In stoichiometric VO2, voltage or joule heating can trigger the transition and activate the volatile behavior. As a result, there is a constant need for such a stimulus to preserve the 1 state. If oxygen vacancies are introduced to the system while maintaining the crystal structure of the VO2 phase, the state 1 can be obtained/written permanently. That is, there is no need for external stimuli to read and recall the data. Here, we have shown the reversibility of the behavior and structure of the VO2 when oxygen vacancies are introduced to and removed from the system. The structure and relaxation mechanism are discussed, as well. This research paves the way for the nonvolatile application of VO2 in neuromorphic devices.