Highly collimated laser beams from grating coupled emission Pb1−xSnxSe/Pb1−xyEuySnxSe diode lasers

Abstract
Grating coupled emission Pb1−xSnxSe/Pb1−xyEuySnxSe double‐heterostructure stripe‐geometry diode lasers were fabricated using molecular beam epitaxy. Low‐divergence far‐field patterns of ∼5° for multimode operation and ∼2° for single‐mode operation were obtained. These are the lowest values ever achieved with Pb salt lasers.