Current-Tunable Lasers with a Narrow Emission Line Operating at 3.3μm.

Current-tunable diode lasers with narrow emission lines for laser spectroscopy in the 3.2-3.4 µm wavelength range are developed. The lasers, based on an InAsSb/InAsSbP double heterostructure, have a widestripe cavity. The wave number increases from 3030 to 3034 cm[sup -1] as the current is raised from 1.5 to 3 times the threshold value at 70 K, while the full width at half-maximum of the laser line decreases from 18 to 10 MHz. It is demonstrated that the linewidth is determined by fluctuations of the cavity resonance frequencies as a result of fluctuations in the concentration of nonequilibrium charge carriers. [ABSTRACT FROM AUTHOR]