Study of enhanced magnetism in Lu doped multiferroic bismuth ferrite

In this work, the enhancement in magnetic moment in Lu doped BiFeO3 is reported. Sol-gel synthesized Bi1-xLuxFeO3 (x = 0, 0.02, 0.04 and 0.05) were characterized for their phase, magnetic properties, thermal analysis and Raman scattering studies. The X-ray diffraction study revealed the segregation of rare earth garnet as secondary phase. The presence of garnet phase was reiterated in the magnetization measurements with Curie temperature at 575 K. The DSC and the Raman spectrum once again ascertain the garnet phase in the compound. We believe that the instability in the structure with lower dopant ionic radii resulted in increase in segregation of garnet and hence enhanced the magnetic moment in rare earth doped BiFeO3 samples. We suggest that the increase in magnetic moment with decrease in rare earth dopant ionic radii reported in the literature could have a strong correlation with the structural instability and the related secondary phase segregation.