The optical absorption of leucosapphire and polycrystalline corundum (polycor) upon coimplantation of iron and chromium ions and subsequent annealing in vacuum is studied. The structure of the states localized in the band gap induced by radiation defects exhibits a higher stability to annealing as compared to implantation of other types of ions into aluminum oxide and to separate irradiation with iron and chromium ions. The governing contribution to the exponential and interband absorption is made by substitutional defects of either type, their clusters, and impurity-vacancy complexes. The effect of incorporated iron ions on the population of levels of chromium-containing defect clusters, on their recharge, and on interaction with intrinsic radiation and biographical defects is revealed. Mixed clusters of substitutional defects are optically active in a spectral range of 2.0-4.0 eV after annealing at a temperature of 1300-1600 K.
ASJC Scopus subject areas
- Surfaces, Coatings and Films