Magnetic resonance and ferromagnetic behaviour in Fe-implanted SrTiO3

Abstract

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. (C) 2009 Elsevier Ltd. All rights reserved.