FERROMAGNETIC RESONANCE AND X-RAY DIFFRACTION INVESTIGATIONS OF ION IRRADIATED AG/FE/AG-(001)-FILMS

High fluence implantation of 95-keV Fe-ion in epitaxial Ag/Fe 200 A/Ag-(001)-multilayers were performed to induce structural modifications. The correlation between structural quality and magnetic properties was investigated by measurements with ferromagnetic resonance (FMR) and out-of-plane x-ray-diffraction techniques (XRD). The FMR results show for fluences up to 1015 cm−2 a decrease of the crystalline- and perpendicular-uniaxial anisotropies, which are attributed to strain relaxation due to the ion-irradiation detected with XRD. From these results the magnetoelastic coefficient B1 is determined to −3×106 J/m3. At higher fluences of 1016 cm−2 we observe a strong reduction of the perpendicular-uniaxial anisotropy and a change of the crystalline anisotropy from cubic towards that of a tetragonal symmetry. Further, increasing fluences lead to a lattice widening above the Fe-bulk value and an increase of the interface roughness.