1.3 µm InAs/GaAs multilayer quantum-dot laser with extremely low room-temperature threshold current density

A high growth temperature step used for the GaAs spacer layer is shown to significantly improve the performance of 1.3 µm multilayer InAs/GaAs quantum-dot lasers. Extremely low room-temperature continuous-wave threshold current densities of 32.5 and 17 A/cm2 are achieved for a three-layer device with as-cleaved facets and high-reflectivity coated facets, respectively.