Room-temperature ground-state lasing using long-wavelength InAs quantum dots on InAlGaAs/InP(311)B

Molecular beam epitaxy was used to grow self-assembled InAs quantum dots on InAl(Ga)As buffer layer/InP (311)B substrates. Their area density was a very high 9/spl times/10/sup 10/ cm/sup -2/ and their room-temperature photoluminescence emission was at 1.6 /spl mu/m. Emission intensity and emission linewidth showed little degradation in the temperature range from 77 K to 300 K. We fabricated lasers using five-period stacked InAs quantum-dot layers for the active region, and achieved 1.6-/spl mu/m ground-state lasing with a low threshold density of 380 A/cm/sup 2/.