High-energy xenon ion irradiation effects on the electrical properties of yttrium iron garnet

Thin monocristalline samples of yttrium iron garnet Y3Fe5O12 (YIG) were irradiated at room temperature with 27 MeV/A 132 Xe ions at varying fluences up to 3.5 x 1012 ions cm-2. Sample thickness (100 μm) was smaller than the mean projected range of ions (170 μm) so that we were able to study the effects of irradiation damage solely. At such a high ion energy the nuclear energy loss is negligible and damage is mainly due to electronic excitation energy loss. YIG d.c conductivity is found to rise by a factor 40 for the highest dose while the permittivity increases only slightly after irradiation (40% max.). The dielectric losses are also enhanced as the ion fluence increases especially at lower frequencies (by a factor 6 at 10 KHz). No dielectric relaxation peak is observed in the frequency range explored here (10 KHz - 10 MHz)