GeSn heterostructure micro-disk laser operating at 230 K

We demonstrate lasing up to 230 K in a GeSn heterostmcture micro-disk cavity. The GeSn 16.0% optically active layer was grown on a step-graded GeSn buffer, limiting the density of misfit dislocations. The lasing wavelengths shifted from 2720 to 2890 urn at 15 K up to 3200 nm at 230 K. Compared to results reported elsewhere, we attribute the increase in maximal lasing temperature to two factors: a stronger optical confinement by a thicker active layer and a better carrier confinement provided by a GeSn 13.8% / GeSn 16.0% / GeSn 13.8% double heterostructure. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement