GaSb-based 2.7µm laser diode with GaAs top cladding

A GaSb-based type-I diode laser heterostructure was grown with a highly mismatched GaAs top clad using MBE. A direct comparison of laser diode characteristics with a conventional structure indicates that despite the fully relaxed clad layer, high peak power >300 mW is generated by these devices. The small increase in the threshold current density and ~27% reduction in the slope efficiency is likely due to increase in the internal loss due to defects.