Novel Phases at Domain Walls

Abstract

In addition to the distinct internal symmetry of domain walls discussed in Chapter 1, local stresses can induce new physical properties at domain walls. In this chapter, we discuss how the intense stress fields generated at the ferroelastic domain walls in some epitaxially strained oxide layers introduce selective chemical modifications, giving rise to novel 2D crystal structures at the walls. In the case of the strained TbMnO3 films presented here, the substitution of Tb by Mn creates a net magnetic moment at each domain wall, thus making them distinct from the bulk-like antiferromagnetic domains. The possibility of tuning the domain wall density with the film thickness makes it possible to tailor the material’s response at the nanoscale.