Abstract

ZnSe crystal has been investigated intensively in recent years as a promising material for generating blue laser emissions. The emission properties of ZnSe are being studied using either electron beam pumping or optical pumping techniques. We investigated the emission characteristics of ZnSe samples using a two-photon picosecond pulse pumping technique and observed blue stimulated emission at room temperature. The ZnSe materials used in this experiment were melt-grown single crystal and MOCVD-grown thin film. The single crystal sample is a cleaved bar size 3.5 × 5 mm 1 mm thick. The thickness of the thin film sample grown on GaAs substrate was ~1 µm. The test sample was pumped by a 3-psec 30-Hz pulsed laser source at 650 nm in room temperature conditions. The light emission along the direction of the cleaved facets was measured using a microscope objective and a spectral detection system. A strong blue emission peak around 475 nm with a linewidth of ~5 nm was observed from the single crystal sample. The dependence of the blue emission intensity on the pumping intensity showed a thresholdlike behavior indicating occurrence of stimulated emission.

© 1991 Optical Society of America