Physical properties of low threshold current 1.25-μm type-II GaInAs/GaAsSb "W"-lasers

Type-II GaInAs/GaAsSb “W” quantum well heterostructures on GaAs show strong potential for temperature-stable data communications lasers. Devices emitting at 1255 nm show promising lasing characteristics including room-temperature threshold current densities, Jth 1 W, and a reduced wavelength temperature dependence of 0.31 nm/C. Temperature- and pressure-dependent characterisation techniques are used to determine the roles of radiative and non-radiative recombination. Analysis of these characteristics suggest a reduced influence of non-radiative recombination on the thermal stability of type-II “W”-lasers compared to type-I devices, as will be discussed along with recommendations for future device development.