InAs/GaAs quantum dot lasers with GaP strain-compensation layers grown by molecular beam epitaxy

Abstract

The strain-compensation (SC) technique to reduce the accumulation of strain is a promising approach to increase the design flexibility as well as the performance of quantum dot (QD) lasers. Here we have studied the application of tensile-strained ultra-thin GaP layers into multiple stacked InAs/GaAs QD grown by MBE. XRD analysis shows the controllability of the average strain in multiple-stacked QD active layer, revealing a reduction in accumulated strain. Fabricated QD laser diodes including thinner QD active layers realized by SC technology show a narrower vertical far-field angle and an increased small signal modulation bandwidth without loss of gain. Cross-sectional SEM image of SC-QD LD active region