Lasing characteristics of InAs quantum-dot microdisk from 3 K to room temperature

We fabricated a microdisk laser with five-stacked InAs quantum-dot (QD) active region, and demonstrated the lasing operation from 3 K to room temperature by femtosecond pulsed photopumping. At room temperature, the threshold power was estimated to be 0.75 mW, when the influence of the surface recombination at the disk edge was neglected. The lasing wavelength was 1.2-1.3 mum, which corresponded to excited states of the QDs. The temperature dependence of the threshold, slope efficiency, lasing wavelength, and linewidth are explained by the rapid increase in nonradiative recombination and internal absorption at critical temperatures of 200-230 K. (C) 2004 American Institute of Physics.