Room Temperature Lasing in 1-μm Microdisk Quantum Dot Lasers

Lasing characteristics of InAs/InGaAs quantum dot microdisks with diameter varied from 1 to 6 μm were studied under optical pumping. The disks were fabricated with standard photolithography and two-step wet etching. We demonstrate room temperature lasing in the 1.29-1.32-μm wavelength range (ground-state transition) in microlasers as small as 1 μm in diameter. The microlasers demonstrate narrow linewidths (40-60 pm), low thermal impedance (85°C/mW), and low threshold powers (50-100 μW).