Electron paramagnetic resonance enhanced crystal field analysis for low point-group symmetry systems: C${}_{2v}$ sites in Sm${}^{3+}$:CaF${}_2$/SrF${}_2$

Abstract

We present a comprehensive spectroscopic study of C${}_{2v}$ point-group symmetry sites in Sm${}^{3+}$:CaF${}_2$/SrF${}_2$ codoped with either NaF or LiF. Data includes electron paramagnetic resonance measurements of Zeeman and hyperfine interactions for the ground state, as well as site-selective excitation and fluorescence spectroscopy up to the ${}^4$G${}_{5/2}$ multiplet. Inclusion of the EPR data allowed us to determine unique crystal-field parameters. The parameters provide information about the geometry of the sites and the nature of the interactions between the Sm${}^{3+}$ dopant and the alkaline earth co-dopant.