We analyze the effect of strain compensation on the crystalline quality of InGaAs/GaAs quantum well gain mirrors that are designed for emission above 1100 nm. The gain mirrors used in this study were grown by molecular beam epitaxy and they utilize GaAsP strain compensation. The effect of strain compensation has been assessed by measuring the curvature of the wafers and by mapping photoluminescence to identify non-emissive dark areas. We present that about 70 % strain compensation is sufficient to prevent dark line defect generation for gain mirrors designed for up to 1170 nm operation. Rapid thermal annealing studies revealed that the strain compensation is efficient in preventing appearance of dark lines even for samples that have been annealed at temperatures as high as 700 °C for a considerable time. Finally, we demonstrate multi-watt operation at 1115-1190 nm using 70-90 % strain compensated gain mirrors.

Date Published: 14 February 2012
PDF: 6 pages
Proc. SPIE 8242, Vertical External Cavity Surface Emitting Lasers (VECSELs) II, 824211 (14 February 2012); doi: 10.1117/12.908094

Published in SPIE Proceedings Vol. 8242:
Vertical External Cavity Surface Emitting Lasers (VECSELs) II
Anne C. Tropper, Editor(s)