Magnetic resonance and magnetization in Fe implanted BaTiO3 crystal

Abstract The results of investigations of the magnetic properties of Fe implanted barium titanate (BaTiO 3 ) perovskite crystal are presented. It has been revealed that the implantation with Fe + ions at a fluence of 0.75×10 17 ions/cm 2 results in the formation of iron nanoparticles with mean size of 5 nm in the implanted surface layer of BaTiO 3 substrate. Room temperature magnetic resonance measurements have shown Electron Paramagnetic Resonance (EPR) spectra originated from Fe 3+ ions in the BaTiO 3 substrate, as well as ferromagnetic resonance (FMR) spectrum from the Fe-implanted surface layer, exhibiting the out-of-plane uniaxial magnetic anisotropy. On the other hand, Vibrating Sample Magnetometer (VSM) measurements of the static magnetization have shown that the composite Fe:BaTiO 3 system displays superparamagnetic response at room temperature, and evident ferromagnetic behavior with an easy-plane magnetic anisotropy at temperature below 100 K. The observed magnetic anisotropy is discussed on a model of strong magnetic dipolar interaction between superparamagnetic nanoparticles of iron within the granular composite film formed in a result of the high-fluence implantation.