Collective phenomena in Dy-doped silver halides in the near- and mid-IR

Abstract

The kinetics of the electronic transitions within the f-shell of Dy3+ ions were studied with monitoring near- and mid-IR luminescence decay under pulsed laser excitation at 1.3 µm. The luminescence decay curves were found to be profoundly non-exponential in all bands in the range between 1.3-5.5 µm. Such behavior is attributed to cross-relaxation and up-conversion processes dominating in relaxation of Dy3+ ions from the laser-excited multiplet 6H9/2+6F11/2. We suggest that strong collective phenomena occurring under relatively low concentrations are due to anomalous clustering of Dy3+ ions. The cross-relaxation enables an efficient population of 6H13/2 and 6H11/2 multiplets, offering this material as an active medium for a 3-µm and 4.3-µm lasers.