1304.4911 (Gaoyang Gou et al.)

Predicted strain-induced isosymmetric ferri-to-ferroelectric transition
with large piezoelectricity    [PDF]

Gaoyang Gou, James M. Rondinelli

We identify a first-order, isosymmetric, transition between a ferrielectric (FiE) and ferroelectric (FE) state in $A$-site ordered LaScO$_{3}$/BiScO$_{3}$ and LaInO$_{3}$/BiInO$_{3}$ superlattices. This unusual electrical analogue to the pervasive ferrimagnetic state in magnetic oxides relies on a geometric field imposed by octahedral rotations and enabled by cation ordering---it decouples the local electric dipoles on the cationic sublattices and directs their cooperative alignment. Epitaxial strains less than 2% are predicted to be sufficient to transverse the phase boundary, across which we capture a $\sim\5$X increase in electric polarization. We describe the electromechanical responses and show that at fixed composition the FiE-to-FE transition may be superior to the polarization reversal found in Pb-based perovskite oxide solid-solutions, enabling piezoelectric technologies under extreme conditions.

View original: http://arxiv.org/abs/1304.4911