Effect of 50 MeV Li 3+ ion irradiation on structural, dielectric and permeability studies of In 3+ substituted Mg–Mn ferrite

Abstract

The 50 MeV Li 3+ ion irradiation induced modifications on structural, dielectric and magnetic permeability properties of Mg 0.9Mn 0.1In x Fe 2− x O 4 ferrites have been studied. The X-ray diffraction studies show that a compressive strain is produced in the lattice after irradiation and the effect of strain is being observed on the dielectric and magnetic permeability properties. The dielectric constant as a function of frequency for unirradiated samples is well explained by Koop’s model. Whereas, for irradiated samples this is explained by the collective contributions of p and n type carriers. The decrease in dielectric constant of irradiated samples in magnitude is explained on the basis of Maxwell–Wagner interfacial polarization. The electric loss parameter for irradiated sample is increased from that of the unirradiated samples and also show the resonance peak, which is explained by the Maxwell–Wagner interfacial polarization. However, the resonance peaks are not present in unirradiated samples. The dispersion in initial permeability follows the same trend for unirradiated as well as for irradiated samples. A small decrease in permeability is observed for irradiated samples. These results are explained by considering the magneto-mechanical effects generated by stress field induced by the ion irradiation in these samples. The magnetic loss in irradiated samples is drastically reduced due to suppression of imaginary part of permeability.