1205.5526 (Andrew T. Mulder et al.)

Interplay of octahedral rotations, antipolar distortions, and cation
ordering in perovskite hybrid improper ferroelectrics    [PDF]

Andrew T. Mulder, Nicole A. Benedek, James M. Rondinelli, Craig J. Fennie

We elucidate the origin of hybrid improper ferroelectricity existing in a wide class of ABO$_3$/A$'$BO$_3$ ordered superlattices from first principles. Using a cubic ABO$_3$ perovskite reference structure, we show how the combination of antipolar distortions sterically induced by octahedra rotations and A-site cation ordering leads to a ferrielectric state. This picture leads to design principles that would otherwise be counter-intuitive and to the possibility of achieving a polar compensation point.

View original: http://arxiv.org/abs/1205.5526