EXCITED-STATE ABSORPTION IN CR3-DOPED GAHNITE GLASS-CERAMICS()

We report on the excited state fluorescence and absorption characteris tics of chromium-doped gahnite glass ceramic. The material is characte rized by a very structured and wide emission spectrum despite Its lowe st excited state being the doubler E-2(g), usually associated with ver y weak electron-phonon coupling. Excited state absorption is principal ly from the doubler E-2(g) to three higher-energy doublets though an a dditional contribution due to the gahnite glass ceramic host is also p resent during UV excitation. The chromium excited state absorption has been extracted from the overall spectrum. Utilizing data from the emi ssion, absorption and excitation spectra, the configuration coordinate diagram describing octahedrally coordinated Cr3+ ions in the gahnite glass ceramic has been produced. From this diagram the expected excite d state absorption spectrum, including the influence of bleaching, has been modelled and a comparison made with experimental data. (C) 1998 Published by Elsevier Science B.V. All rights reserved.