Role of electronic energy loss on the magnetic properties of Mg0.95Mn0.05Fe2O4 nanoparticles

Effects of 100 MeV Si7+ and Ni8+ ion irradiation on Mg–Mn ferrite nanoparticles have been studied. The bulk sample was synthesized using the solid-state reaction technique. For obtaining nanoparticles, the bulk sample was milled using high-energy ball mill for 12 h. The well-characterized nanoparticles having an average particle size of ∼6 nm were irradiated with 100 MeV Si and Ni ions at various fluences in the range 5 × 1012–5 × 1013 ions/cm2 to see the effects of increasing electronic energy loss on their magnetic properties. The magnetization measurements performed on the 100 MeV Si ion irradiated nanoparticles sample revealed that the values of coercivity and the saturation magnetization have been enhanced about two times as compared to the unirradiated sample. It is explained on the basis that after irradiation by 100 MeV Si ions, the surface states pinning of domains is released which causes enhancement in the saturation magnetization and coercivity. On the other hand, the saturation magnetization decreases slightly after irradiation by Ni ions. The results have been explained on the basis of electronic energy loss dependence in the nanoparticles.