Excited-state absorption (ESA) spectrum of Cr4+:Mg2SiO4 (forsterite) was analyzed by electronic-state calculation method independent of ligand field theory. Both the ESA’s from the first-excited states in 3T2(et2) triplet and 1E(e2) singlet terms were considered. Two ESA-dominant peaks apparently shown in experimentally obtained spectrum in literature were confirmed to have originated from 3A”[3T2(et2)] → triplets transitions. It was revealed that the region 13 000-14 000 cm−1 should have ESA’s also for E//b and E//c polarizations. By comparing theoretically obtained oscillator strength with one obtained by an experiment, authors pointed out that effective Cr4+ concentration was one order of magnitude largely estimated in the literature.
© 2001 Optical Society of AmericaPDF Article