Evidence of ferroelectricity in ferrimagnetic kappa-Al2O3-type In0.25Fe1.75O3 films

摘要

We report direct evidence of the multiferroic nature of the kappa-Al2O3-type InxFe2-xO3 films (x = 0-0.25) grown on the SrTiO3(111) substrates at room temperature. The kappa-Al2O3-type InxFe2-xO3 films show a clear saturated and opened P-E hysteresis loop at room temperature with a remnant polarization of 1.8 mu C cm(-2). Also, the ferrimagnetic-incommensurate magnetic phase transition is observed at 205 K, which is compatible with the recent report on the In0.24Fe1.76O3 nanorods. The results indicate that the substitution of Me3+ ion, which has a larger ionic radius than Fe3+, is effective to grow good insulating ferroelectric kappa-Al2O3-type Fe2O3 films, leading to the genuine multiferroic nature. Published by AIP Publishing.