Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

Polycrystalline alumina samples (α-Al₂O₃, purity: 99.8%) were irradiated by ⁶³Cu heavy ions (E = 0.5 MeV/u) at various fluences. After irradiation, absorption measurements were performed within the wavelength range from 200 to 1000 nm to evaluate color center evolution. Thermal annealing behavior of the created defects was investigated with respect to annealing temperature and duration. Complex color center formation processes depending on particle fluence and temperature could be observed. Calculated activation energies necessary for F- and F+-center migration are ∼0.3 eV for temperatures ranging from RT to ∼673 K.