Lasing in compact injection microdisks with InAs/InGaAs quantum dots

We present results of characterization of injection microdisk and microring lasers with InAs/InGaAs self-organized quantum dots grown on a GaAs substrate. The microresonator diameters are within 9-31 μm. The microlasers operate without external cooling in continuous wave regime at room temperature and up to 100°C. In case of ring resonator geometry, a reduction of threshold current in comparison with the disk resonator is observed, that is due probably to reduction of current waste in the center of the resonator where field of whispering gallery lasing modes is negligible. This also indicates that the effects of non-radiative surface recombination and carrier diffusion are insignificant for QD-based microlasers.