Abstract

We describe high-brightness, broad area midinfrared semiconductor lasers. The laser structures incorporated 14 type-II quantum wells imbedded in thick waveguide/absorber regions composed of InGaAsSb. The optically pumped devices achieved higher brightness operation as unstable resonators (UR). The UR’s were fabricated by polishing a diverging cylindrical mirror on one of the facets. For a 4 mm UR operating at λ=4.7µm and at 35 × threshold the device was observed to be diffraction limited. In comparison a standard Fabry-Perot laser was many times diffraction limited.

© 2010 Optical Society of America