Impact of Gd and Cu substitution on dielectric and magnetic properties of MnFeO₃ multiferroic materials

Gadolinium (Gd) and copper (Cu) substituted MnFeO₃ nanoparticles were synthesized via sol gel auto-combustion route. In imaginary electric modulus Debye peaks occurred which indicated the phenomenon of relaxation in the given frequency range. Cole-Cole plots were taken to investigate the contribution of grain and grain boundaries. The grain boundary resistance increased as compared to grain resistance with the incorporation of Gd and Cu. Magnetization and remanence were observed to decrease while coercivity (H_c) increased with Gd-Cu substitution. The phenomenon of super exchange interaction takes place between cations which reside on tetrahedral and octahedral sites. The magnetic ordering and spin canting were distorted with the substitution of Gd and Cu which leads to decrease in magnetic properties. The value of coercivity was raised upto 1992 Oe which proposed that synthesized multiferroics are useful in the fabrication of perpendicular recording media.