Very-low-threshold current density continuous-wave quantum-dot laser diode

Data are presented showing that a quantum-dot laser diode can achieve a continuous-wave room-temperature threshold current density as low as 11.7 A/cm². The broad-area laser diode operates at a wavelength of 1.22 mum and delivers a power level of 0.42 W with 40% maximum slope efficiency in p-up mounting without heatsinking. Spectral measurements indicate the onset of stimulated emission at ~6 A/cm².