We report first-principles calculations, within the density functional theory, on the structural and energetic properties of 180 - stripe domains in (PbTiO 3) n/(SrTiO 3) n superlattices. For the explored periodicities (n=3 and 6), we find that the polydomain structures compete in energy with the monodomain phases. Our results suggest the progressive transition, as a function of n, from a strong to a weak electrostatic coupling regime between the SrTiO 3 and PbTiO 3 layers. Structurally, they display continuous rotation of polarization connecting 180 domains. A large offset between  atomic rows across the domain wall and huge strain gradients are observed. The domain wall energy is very isotropic, depending very weakly on the stripe orientation.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 16 May 2012|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics