Correlated oxide phase transition switch: A paradigm in electron devices

Alternate information processing state variables and computing architectures are an active area of research given the rapidly approaching physical limitations of conventional CMOS scaling. In this context, it may be worth exploring the idea of ultra fast phase transitions in correlated oxides as a basic switching element that can be used in CMOS-like or neural circuits or other high-frequency circuit components in photonics. The basic paradigm is to trigger an insulator-to-metal phase transition in a correlated oxide with an external perturbation in form of thermal, electrical, optical, or magnetic excitations, while switching off upon the removal of the applied external excitation. Vanadium dioxide (VO2) is a correlated oxide that undergoes a sharp insulator-to-metal transition (IMT) near room temperature (∼340K for single crystals) with several orders of magnitude of resistance change. In this presentation, we discuss results on electrical triggering of the phase transition in VO2 devices fabricated on semiconductor platforms such as Si and Ge along with studies on elementary semiconductor physics associated with such materials as a device component.