Optical spectroscopy and modeling of Fe2+ ions in zinc selenide

In this work, we collect absorption and emission spectra for Fe2+ ions in zinc selenide (Fe:ZnSe) and identify trends from 10.5 to 300 K in absorption and from 5 to 300 K in emission. The absorption spectrum is used to determine free parameters in historical eigenvalue expansions for Fe2+ ions in tetrahedral potentials as described by Slack, Ham, and Chrenko. Additionally, we measure the change of the fluorescence lifetime of Fe2+ ions in ZnSe with respect to temperature from 5 to 300 K. A model of the behavior is developed and fit to the collected lifetime data. Results are compared with previously published values of the fluorescence lifetime of Fe:ZnSe and notable discrepancies are attributed to concentration-dependent effects.