Jm. Costantini et al., STRUCTURAL MODIFICATIONS OF YTTRIUM-IRON-GARNET AFTER HIGH-ENERGY HEAVY-ION IRRADIATIONS, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 80-1, 1993, pp. 1249-1254
Irradiation of thin epilayers of yttrium iron garnet (YIG) was perform
ed at room temperature with 50 MeV S-32, 50 MeV Cu-63 and 235 MeV Kr-8
3 ions, for which the energy loss in the targets was mainly due to ele
ctronic excitation and ionization. The resulting damage was studied by
high-resolution X-ray diffraction (HRXRD) and transmission electron m
icroscopy (HRTEM). In the case of Kr irradiation, both HRXRD and HRTEM
showed that YIG was progressively amorphized by the increasing track
overlap, while in the case of S and Cu irradiations, HRTEM showed that
some recrystallization of the amorphous tracks occurred, leading to g
rain sizes around 10 nm. It is concluded that these processes are trig
gered by the electronic energy loss. Previous resistivity and saturati
on magnetization measurements are discussed with respect lo the presen
t structural data.