Magnetic properties of Co-implanted BaTiO3 perovskite crystal

The results of electron magnetic resonance (EMR) and magnetization measurements of Co-implanted barium titanate (BaTiO3) perovskite crystal are presented. It has been revealed that the implantation with Co on different fluencies of metal concentrations produces a granular composite film in the surface layer of BaTiO3 substrate, which exhibits remarkable ferromagnetic behavior. EMR measurements revealed spectra originated from iron impurities of BaTiO3 substrate. Ferromagnetic resonance spectra from Co-implanted surface layer, exhibiting an out-of-plane uniaxial magnetic anisotropy, were also observed. The magnetization measurements performed in various geometries show that the ferromagnetic Co:BaTiO3 system displays easy-plane magnetic anisotropy. It has been shown that the magnetization and coercivity of ferromagnetic state depends on the fluence of implantation. The observed phenomena are discussed on the basis of strong magnetic dipolar interaction between Co nanoparticles inside the granular composite film formed as a result of implantation.