Radiative color centers in doped sapphire crystals

Experimental and theoretical results of investigation of the spectral properties of sapphire (α-Al2O3) single crystals are analyzed. Crystals grown under different conditions, both nonactivated and activated with impurity ions of the iron group (Cr, V, Mn, Fe, Co, Ni), primarily with chromium ions, were investigated before and after irradiation with photons and high-energy electrons. It is shown that the impurity composition of crystals significantly affects the radiative and optical properties and the character of changes in the electronic state of impurities.