Enhancement of Multiferroic and Optical Properties in BiFeO₃ Due to Different Exchange Interactions Between Transition and Rare Earth Ions

An experimental analysis of the Bi0.90Tb0.1Fe0.90Mn0.1O3 system synthesized via the solid-state method is presented in this report. UV-visible measurements are carried out and a smaller bandgap (i.e., semiconductor-type behavior) is obtained. The structural phase of the present system is analyzed with X-ray diffraction and neutron diffraction measurement. Structural-phase analysis reveals that the system contains two nuclear phases (rhombohedral structure [R3c space group] with orthorhombic [Pn21a space group]). Moreover, also more bending in the bond angle is found, and the existence of a magnetic phase with a nuclear phase for the Bi0.90Tb0.1Fe0.90Mn0.1O3 system is also confirmed by neutron diffraction. The magnetic moment versus temperature (M-T) curve demonstrates that the system's Neel transition temperature is at 568 K. The magnetization data show enhancement in the magnetic property by displaying the weak ferromagnetic-type behavior at room temperature in the magnetic field versus magnetic moment (M-H) curve as compared to the parent compound. From dielectric measurement, the dielectric constant increases while the loss decreases.