Reactive walls

摘要

Interfaces between different oxide materials have been attracting much attention. They are seen as a source of new properties and functionalities. Engineering these borders has already revealed phenomena such as conductivity and superconductivity at the frontier between insulating compounds, and magnetism between non-magnetic materials'. In fact, it is not even necessary to combine different materials to create interfaces. Ferroic materials such as ferromagnets, ferroelectrics and ferroelastics naturally break into domains characterized by different orientations of the material's spontaneous ferroic order - magnetization for ferromagnets, electric polarization for ferroelectrics and macroscopic deformation for ferroelastics. These domains are separated by interfaces called domain walls. On page 379 of this issue, Farokhipoor et al. highlight that, instead of being a passive region that accommodates the different ferroic-order orientations of the domains that border it, a domain wall can also be a reactive area that generates and stabilizes new two-dimensional crystallographic phases not achievable by conventional means.