Mid-IR spectroscopy of Fe:ZnSe quantum dots

Abstract

We report spectroscopic characterization of Fe:ZnSe quantum dots (for 2% of Zn/Fe molar ratio) fabricated by microemulsion hydrothermal synthesis. Mid-IR photoluminescence of the E-5 <-> T-5(2) transition of Fe2+ ions over 3.5-4.5 mu m spectral range was observed in Fe:ZnSe quantum dot samples and kinetics of luminescence have been characterized at temperatures of 30-300 K under direct (2.788 mu m) mid-IR excitation and indirect (0.355 mu m) photoionization excitation. The radiative lifetime (trad) was estimated from these measurements to be 48 mu s while lifetime at room temperature was measured to be 440 ns. This agrees closely with the behavior of bulk material. (C) 2016 Optical Society of America