Magnetic studies of multiferroic Bi1-xSmxFeO3 ceramics synthesized by mechanical activation assisted processes

Bi1-xSmxFeO3 (x = 0.0-0.2) ceramic samples were prepared by mechanical activation assisted solid-state-reaction synthesis. A stoichiometric mixture of Bi2O3, Sm2O3, and Fe2O3 powders was mechanically milled and this was followed by heat treatment at 700 degrees C for 1 h. Room temperature x-ray diffraction patterns confirmed the formation of perovskite structured Bi1xSmxFeO3 phase. Vibrating sample magnetometry measurements showed that to a certain extent, Sm doping of BiFeO3 leads to increased magnetization and a sharp magnetic transition at similar to 380 degrees C. Mossbauer spectroscopy confirmed the presence of single-phase material for the doped compositions whereas electron paramagnetic resonance analysis showed the effect of doping on the variation in the degree of canting in the samples. At doping levels of 10 at.% Sm, the improvement in the magnetic behaviour appears to arise from a combination of the propensity of the samples to form pure phase material, partial destruction of spin cycloids, increased canting of spins and interaction between magnetic ions.