The mechanisms of slow bleaching in YAG:Cr~(4+) under CW pumping

摘要

We report on the results of lasing and spectroscopic investigations of the anomalously slow recoverable bleaching of Cr,Ca:YAG and Cr,Mg:YAG crystals. We propose two models for this effect: (i) Cr~(4+) reduction to Cr~(3+)due to oxygen valence band electron capture by Cr~(4+), and (ii) induced disorder in Cr~(4+) tetrahedral center due to effect of oxygen vacancies.