Lifetime of the high-power QD laser is improved

While quantum-dot (QD) lasers have attracted considerable attention for their potential to attain high power output with low current requirements, their reliability is rarely reported. The question is whether indium arsenide/gallium arsenide (InAs/GaAs) QD lasers can survive with age, due to the large lattice misfit between the self-assembled InAs QDs and the surrounding GaAs barrier layers in the active region. In response, scientists at the Chinese Academy of Sciences (Beijing, China) have demonstrated improved lifetime of a semiconductor QD laser designed as five stacked InAs/GaAs QDs separated by an InGaAs strain-reducing layer (SRL) and a GaAs spacer layer as an active medium.