Effects of argon ion irradiation on structural and magnetic properties of Tb/Fe multilayers

The effects of Ar-ion irradiation and thermal annealing on structural and magnetic properties of crystalline Tb/Fe multilayers have been studied using small-angle X-ray diffraction (SAXRD) and conversion electron Mössbauer spectrometry (CEMS). The mixing of layers Tb/Fe caused by irradiation with 360 KeV Ar ions and fluences exceeding 2×1015 Ar/cm2 is clearly observed, which can be explained by the ballistic model. The mixing efficiency saturates at high fluences and it still remains a crystallized Fe part. At high fluences and after annealing at 873 K, the Tb/Fe interface exhibits magnetic properties of amorphous alloys. The crystalline terbium is found to be sensitive to the nuclear damage.