Molecular beam epitaxy of vertical-emitting microcavity lasers for the 6–8micron spectral range operating in continuous-wave mode

Molecular beam epitaxial growth of continuous-wave (cw) midinfrared IV–VI vertical-cavity surface-emitting laser structures is presented. From the structures, based on high-finesse microcavities and containing PbSe as active medium, optically pumped cw laser emission is observed at very long wavelengths between 7.9 and 6.7 μ m . Stimulated emission is found up to temperatures of 100 K . We achieved internal threshold pump intensities below 25 W / cm 2 , which is two orders of magnitude smaller than those reported so far. The observed line width of the laser emission is only 0.6 nm , with a strong line width narrowing above threshold as compared to the line width of the cavity resonance. Cw output powers are up to 4.8 mW .