1.55 μm band low-threshold, continuous-wave lasing from InAs/InAlGaAs quantum dot microdisks.

InAs/InAlGaAs quantum dot active layers within microcavity resonators offer the potential of ultra-low-threshold lasing in the 1.55 μm telecom window. Here, we demonstrate the first quantum dot microdisk laser with single-mode emission around 1.55 μm under continuous-wave optical pumping up to 170 K. The extracted threshold is as low as 32 μW at 77 K. This result lays the foundation of an alternative to quantum-well microlasers for low-threshold and highly compact monolithically integratable light emitting sources in fiber communication.