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 Å/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 ${10}^{15}$ ${\mathrm{cm}}^{\text{−2}}$ 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 $B_1$ is determined to $\text{−3}$ ×${10}^6$ ${\mathrm{J/m}}^3$ . At higher fluences of ${10}^{16}$ ${\mathrm{cm}}^{\text{−2}}$ 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.