Alignment-relaxed 1.55 µm multiquantum welllasers fabricated using standardburied heterostructure laser processes

Abstract

A mode-expansion laser that can be fabricated by standard buried heterostructure laser processes without introducing any extra complex processing steps is demonstrated. With the diluted waveguide structure, the originally strongly guided laser mode can be expanded and better matched to the weakly guided fibre mode. Both the coupling efficiency and laser-to-fibre alignment tolerance are improved. Such a laser structure has a great potential to reduce the cost of laser diode modules.