Abstract

Near infrared semiconductor lasers, operating in the 0.6–2.0-μm wave-length range, for gas monitoring applications is a fast-growing area. Semiconductor lasers have many advantages such as room temperature operation, several mW of output power in a single longitudinal mode, and compatibility with silica fibers and a variety of other fiber-optic components already developed. Commercially available semiconductor lasers are today optimized for the communication market, that in many cases favorize parameter settings of the laser structure in adverse of what is desired for spectroscopic use. Therefore, advanced multisection laser structures such as DFB (Distributed Feed Back) and DBR (Distributed Bragg Reflector) lasers are a necessity since each section can be controlled individually to a final performance opti­mized for spectroscopical need, such as large tunability, high SMSR (side mode suppression rate), and a low level of higher order harmonics of the modulation signal.

© 1994 IEEE