InAs/InGaAs/GaAs quantum dot lasers of 1.3μm range with enhanced optical gain

摘要

Near-1.3μm lasers based on multiple layers (2, 5 and 10) of InAs/InGaAs/GaAs quantum dots with high performance have been grown by molecular beam epitaxy. A record differential efficiency as high as 88% was achieved in laser based on 10 QD layers. Threshold current density of 100-150 A/cm~2 and differential efficiency of 75-80% were achieved simultaneously in the same device. Characteristic temperature of 150K in 20-50℃ temperature range was demonstrated for the laser based on 5 QD layers. A steep increase in internal loss with decreasing cavity length was found to limit the highest mirror loss possible for ground state lasing.