ATOMIC DISPLACEMENTS AND ATOMIC MOTION INDUCED BY ELECTRONIC EXCITATION IN HEAVY-ION-IRRADIATED AMORPHOUS METALLIC ALLOYS

In amorphous metallic alloys irradiated with swift heavy ions, electronic excitation induces atomic displacements at the beginning of the irradiation and anisotropic growth above an incubation fluence. We provide here an extensive review of our data on amorphous Fe85B15 (including work that is already published), as well as a general description of the topic. Samples were irradiated at various temperatures (20 K, 90 K, 223 K) with a large variety of high-energy (GeV) heavy ions (Ar to U). The atomic rearrangements occurring during irradiation were studied by in situ electrical resistance experiments. The influence of the irradiation geometry as well as of a uniaxial stress applied to the sample was investigated. The whole set of data is accounted for with a two-hit phenomenological model allowing one to extract physical parameters. A description of the ion-target interaction on the basis of the Coulomb explosion mechanism is also provided.