Lattice dynamics in improper ferroelectric YGaO3

Andryushin, N. D.; Pavlovskiy, M. S.; Zinenko, V. I. Ferroelectrics.

The structural phase transition P63/mmc → P63cm in hexagonal YGaO3 crystal is studied by first-principles methods. From lattice dynamics calculations it was obtained that the mechanism of transition into polar phase is similar to the one in isostructural YMnO3 crystal. As a result of calculations the improper ferroelectricity and electrical polarization were revealed in YGaO3.