Magnetic resonance and ferromagnetic behaviour in Fe-implanted SrTiO3

The results of magnetic resonance and magnetization measurements of Fe-implanted strontium titanate (SrTiO3) are presented. Electron paramagnetic resonance (EPR) spectra including resonance lines due to the paramagnetic Fe3+-V o site with axially disturbed ligand field, and due to S-state Fe3+ ions (S=5/2 and L=0) substituted into the titanium site coordinated by six oxygen atoms in the Ti4+-centered unit cell, were observed. It has been revealed that the implantation of Fe ions into SrTiO3 produces a remarkable ferromagnetic behavior. The ferromagnetic resonance (FMR) and magnetization measurements revealed an out-of-plane uniaxial magnetic anisotropy in Fe-implanted SrTiO3. The observed phenomena are discussed on the basis of strong magnetic dipolar interaction between Fe nanoparticles due to the decreasing interparticle distance with increasing implantation fluence.