Characterization Of Er3+-Doped Glasses By Fluorescence Line Narrowing

The Stark levels of the 4115/2 ground state manifold have been determined for Er3+-doped fluoride, fluorophosphate, and silicate bulk glasses from fluorescence-line-narrowing measurements at 4.2 K. Splittings between adjacent Stark levels were observed to be 20-80 cm-1. The total energy spread of the manifold ranged from 335 to 400 cm-1. The energy of a given Stark level varied up to 60 cm-1 depending on the particular Er3+ sites excited. Using the 4.2-K results, homogeneous broadening is found to be a reasonable approximation for the 300-K luminescence band.