Fluorescence-line-narrowing Zeeman spectroscopy of Cr3+-doped silicate and Li borate glass

Abstract

This paper discusses the inhomogeneous broadening of the 2E to 4A2 emission (R line) in Cr3+-doped glasses. The impurity ion occupies approximately octahedral sites in silicate and borate glasses in which the R-line transition is broadened by site-to-site disorder associated with the glassy structure. The spectroscopic effects of disorder are to some extent removed by fluorescence line narrowing (FLN), which seeks to recover the homogeneous width of the R-line transitions. In the three glasses investigated, two silicate and a Li borate glass, the R-line width is approximately=190-200 cm-1. In magnetic fields up to 3.46 T and at low temperatures (T approximately=2 K) the narrowed R line splits into three components, one resonant with the excitation and two shifted to longer wavelengths.