THEORETICAL AND EXPERIMENTAL INVESTIGATION OF IV-VI MID-IR MQW VCSELs

Mid-infrared section of the optical spectrum is §typically between 3 to 30 m wavelengths. This area §represents optical absorption of a wide range of §chemical and organic compounds. Mid-IR absorption §spectroscopy is one of the known highly accurate §chemical analyses. There are several requirements §for the light source used in such techniques. §Thermal stability, tunability, monochromaticity, and §sufficient power output are a few vital elements of §such a system. Lead salt lasers are one of the known §sources for mid-infrared light. They can cover 2.9 §to 27 m wavelength. The main difficulty of lead §salts is their poor thermal conductivity. This §prevents the traditional edge-emitting laser to §operate continuously (i.e. CW mode) at room §temperature. CW mode is a necessary condition, since §any spectral analysis needs a light source with §minimum harmonics. To this date, the highest §temperature CW mid-IR available is around 223K, §which is still well below thermoelectric cooling §range (i.e.~260K). The main goal of this research is §to assist the development of an innovative light §source that can be installed in a portable optical §spectroscopy unit.