Enhanced multiferroic characteristics in hexagonal ScMn1−xFexO3 ceramics

In the present study, enhanced antiferromagnetic characteristics and room temperature magnetoelectric coupling are achieved by Fe-substitution for Mn in h-ScMnO3. The antiferromagnetic Néel temperature (TN) increases from 131 K for ScMnO3 up to 140 K for ScMn0.8Fe0.2O3. Electric field controlled magnetism is confirmed for ScMn0.8Fe0.2O3 at room temperature, combining with the short-range magnetic spin ordering. The Rietveld structural refinement and selected area electron diffraction confirm the noncentrosymmetric P63cm structure for the present ceramics. The ferroelectric domain walls at the atomic scale are determined by the aberration-corrected high-angle annular dark-field scanning transmission electron microscopy; meanwhile, the spontaneous polarization of 5.6 μC/cm2 is determined. The noticeable magnetoelectric coefficient αME ∼ 0.78 mV/cm Oe (measured under a magnetic field up to 3000 Oe) is obtained in ScMn0.8Fe0.2O3, which is quite stable with the applied magnetic field, reflecting coupling of the short-range spin ordering with the ferroelectric ordering. The enhanced antiferromagnetic behaviors are discussed with the effect of Fe-substitution, which reduce the magnetic frustration and enhance the exchange interaction.