From Phonons to Domain Walls, the Central Peak and “Critical Slowing Down”

Abstract

We investigate perovskite oxides from different perspectives, namely their pseudo-harmonic dy-namical properties, their dynamical properties when strong anharmonicity exists, and the intri-guing functionalities arising from domain walls. Taking these viewpoints together yields a rather complex picture of this material class, which has not been found in previous approaches. It opens pathways to novel applications and reveals the rich ground states beyond the fictitious belief in the ‘simplicity of perovskites and such structures’.