Luminescence and structure of energy levels of the Co2+ ions in the yttrium aluminum garnet

In experiments on irradiation of single crystals of yttrium aluminum garnet doped with cobalt (0.1 mol %) with pulsed high-current electron beams, the intense luminescence of Co2+ ions with a well-developed fine structure of bands (pulsed high-current cathodoluminescence) was observed in the visible region at room temperature. On the basis of the general Tanabe-Sugano diag rams and luminescence spectra, energy level diagrams of the Co2+ impurity i ons located in octahedral and tetrahedral sites were constructed.