New magnetic properties by ion beam mixing: Ag/Fe/Ag-(0 0 1)-films with tetragonal symmetry

In the thermally immiscible Ag/Fe (5-20 nm)/Ag-(0 0 1)-multilayer-structure ion beam mixing of the layers induces a strong tetragonal distortion of the Fe-layer. The induced changes of the magnetic properties were determined by the ferromagnetic resonance (FMR) and Faraday magnetometry (FM) methods. For high dose irradiated samples of 1016 cm-2 a tetragonal symmetry of the magnetic anisotropy fields was observed. An influence of the ion beam mixing on the saturation magnetisation of the Fe-layer was not detected. Annealing of the samples shows a recovery of the magnetic properties at 450-600 K indicating the influences on the magnetic properties are mainly caused by induced atomic intermixing of Ag in the Fe-layer and Fe in the Ag-layer