Luminescence of Cr-doped alumina induced by charged particle irradiation

The ion-induced luminescence behavior and damage processes were investigated for Cr-doped alumina (ruby, α-Al₂O₃: 0.5 wt% Cr) under H and He ion irradiation with incident energies from 0.2 to 3.0 MeV. The total yield of the R-line luminescence (693 nm) was proportional to the projected range of the incident H ions. However, the He induced luminescence yield was not directly related to either the projected range or the incident energy. The ion-induced luminescence efficiency for the H ion was independent of the electronic energy loss, and that for the He ion decreased with increasing the electronic energy loss. The yields of the R-line luminescence rapidly diminished at the beginning of the ion irradiation. The reduction rate of the luminescence was adequately explained in terms of the nuclear energy deposition, indicating that the R-line luminescence centers were damaged by nuclear collisions.