Temperature and concentration quenching of mid-IR photoluminescence in iron doped ZnSe and ZnS laser crystals

Concentration dependences of the mid-IR kinetic of luminescence at E-5 <-> T-5(2) transition in Fe:ZnSe and Fe:ZnS laser samples were studied in 14-300 K temperature ranges. Radiation lifetime in Fe:ZnSe samples measured using low doped samples with iron concentration 0.1 x 10(18) cm(-3) was estimated to be 57 mu s. The magnetic susceptibility for higher doped (C-Fe=38 and 112 x 10(18) cm(-3)) Fe:ZnSe samples was found to consist of a paramagnetic Curie-Weiss behavior arising from the weakly interacting Fe2+ ions and a diamagnetic ZnSe contribution plus a temperature-independent, field-dependent contribution possibly arising from very small amounts of aggregated Fe. (C) 2011 Elsevier B.V. All rights reserved.