Study of the defect in the CaF2 materials via a laser-induced fluorescence measurement

Analysis of defects in optical materials is crucial for their applicability in cutting-edge optical components. Since calcium fluoride (CaF2) is highly regarded for optical applications, understanding the nature of defects within CaF2 is particularly significant. These defects have been conventionally identified through absorption and photoluminescence (PL) emission studies. In this work, we investigate the defects by measuring laser-induced fluorescence (LIF) spectra over a long irradiation. By decomposing the PL spectrum into multiple Gaussian PL bands, we identify the defects within the CaF2 material. The measurement of irradiation-induced PL can be rationalized by the stabilization of F-centers via the formation of M-centers. PL mapping has been also studied to study the potential link between the surface oxygen contamination of CaF2 samples and polishing techniques.