Vortex Domain Walls in Ferroelectrics.

Controlling the domain formation in ferroelectric materials at the nanoscale is a fertile ground to explore emergent phenomena and their technological prospects. For example, charged ferroelectric domain walls in BiFeO and ErMnO exhibit significantly enhanced conductivity which could serve as the foundation for next-generation circuits (Estévez and Laurson, , , 054407). Here, we describe a concept in which polar vortices perform the same role as a ferroelectric domain wall in classical domain structures with the key difference being that the polar vortices can accommodate charged (., head-to-head and tail-to-tail) domains, for example, in ferroelectric PbTiO/dielectric SrTiO superlattices. Such a vortex domain wall structure can be manipulated in a reversible fashion under an external applied field.