Ferrotoroidic polarons in antiferrodistortive SrTiO3

Abstract

Discovery of new quasiparticles with nontrivial topological field textures, such as polar vortices, skyrmions, and merons, holds promise in technological paradigms. Here, the authors demonstrate a ferroelectric quasiparticle with topological polarization vortices by engineering excess electron polarons. They further show that the electron polaron carries a magnetic moment coupled with ferrotoroidicity, i.e., the magnetoelectric effect. This result provides insight into the ultimate miniaturization of ferrotoroic materials and a new class of functional polaron families.