Observation of lasing from Cr2+:CdTe and compositional effects in Cr2+-doped II-VI semiconductors

Abstract

We are engaged in a systematic study of the optical and laser properties of Cr2+-doped cadmium chalcogenides. Previously, we demonstrated quasi-continuous wave lasing from Cr2+-doped Cd0.55Mn0.45Te with slope efficiencies as high as 64% and a laser tuning range from 2,170-3,010 nm. In this paper, we report the first demonstration of lasing from Cr:CdTe at room temperature. Pulsed-laser operation was obtained with a free-running spectrum centered at 2,535 nm. The slope efficiency of the laser was low (∼1%) because of large parasitic losses at the laser wavelength. The spectroscopic properties of Cr:CdTe are favorable for laser applications because of a large emission cross section (∼2.5 × 10-18 cm2) and a high emission-quantum yield (∼88%). In addition, CdTe can easily incorporate Cr ions either through melt growth or diffusion doping. Along with our results on Cr2+:CdTe, we report on the optical properties of several other Cr2+-doped II-VI semiconductors (ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, Cd0.9Zn0.1Te, Cd0.65Mg0.35Te, Cd0.85Mn0.15Te, and Cd0.55Mn0.45Te) and compare them for applications as solid-state laser materials.