Modification of magnetic anisotropy in ferromagnetic metallic glasses using high energy ion beam irradiation

The modification in the magnetic anisotropy introduced by swift heavy ion irradiation has been investigated. Ferromagnetic metallic glasses Fe78B13Si9 and Fe40Ni38Mo4B18 have been irradiated with 100 MeV 127I ions at different doses from 5×1012 to 7.5×1013 ions/cm2. Magnetic anisotropy has been studied by measuring the relative intensity ratio D23 of Mossbauer sextet. As received samples display orientation of the magnetic moments nearly parallel to the surface of the ribbon, which upon irradiation to a dose of 5×1012 ions/cm2 rotates to a nearly random orientation. At the dose of 7.5×1013 ions/cm2, the magnetic moments display completely random orientation.