Multiferroic behaviour of YMnO3 and YbMnO3 epitaxial films

YMnO3 has an antiferromagnetic (AFM) transition at 76 K with a ferroelectric (FE) transition at much higher temperature. For that reason, it is a so-called multiferroic material. Recently, anomalies in the relative dielectric permittivity in YMnO3 near the Neel temperature were recognized. In the present study, coupling between the ferroelectric domain switching and the AFM spin ordering is demonstrated. On the other hand, magnetic field-induced ferromagnetism was recognized in a ferroelectric YbMnO3 epitaxial film. The magnetic frustration behaviour of this ferroelectric and ferromagnetic YbMnO3, a real multiferroic material, is also described.