Ferroelectric properties of multiferroic hexagonal er MnO<inf>3</inf> thin films

The authors investigated the ferroelectric properties of epitaxial thin films of hexagonal ErMnO3 fabricated on Pt(111)Al2O 3(000l) substrates. The ferroelectric characteristics were observed with a reasonable remnant polarization value (3.0 μC/cm2 at 160 K). However, the films exhibited an unusual antiferroelectric-like behavior with a temperature- and an electric-field-dependence. The coercive field showed an abrupt increase below the antiferromagneitc ordering temperature, indicating the possibility of interference between ferroelectric domains and antiferromagnetic domains.