Abstract :
The effect of Sr-doping on ferroelectricity and ferromagnetism at room temperature has been studied for Bi0.8La0.2Fe0.9Mn0.1O3 ceramic system. X-ray diffraction shows that a structural phase transition occurs from rhombohedral structure of BiFeO3 (space group R3c) to orthorhombic structure of Bi0.8La0.2FeO3 (space group C222). Substitutions of Sr-ions in Bi-site and Mn-ions in Fe-site do not induce any further structural change. Moreover, doping of Sr-ions plays a crucial role to obtain single phased samples. DTA and TGA studies show that both the magnetic transition temperature ( T M ) and the ferroelectric transition temperature ( T C ) decrease for Bi0.7Sr0.1La0.2Fe0.9Mn0.1O3. Sr-doping enhances the ferroelectric property by increasing the electric polarization. M – H measurement shows that Sr-ions partially destroy the spin cycloidal structure in it giving rise to weak ferromagnetism (nonlinearity) at room temperature.
