Uncovering origin of unconventional ferroelectricity in HfO2 for neuromorphic applications

Abstract

Although the recently discovered orthorhombic HfO2 exhibits strong ferroelectricity in thin film phase, the origin of many unconventional phenomena are unknown such as large coercive field, slow domain propagation and multiply-switchable polarizations. Here we present our recent theoretical investigations, using first-principles calculations and numerical simulations, for the origin of the phenomena. We discovered unusually weak interactions between ferroelectric domains at an atomic level are responsible, and will discuss about how to reduce the coercive, tune the domain speed and effectively utilize the multiple polarizations for neuromorphic applications.