Low threshold CW lasing of closely-stacked self-organized InAs/GaAs quantum dots

We achieved low threshold CW lasing of a new type of self-organized dots. The dots have a columnar shape, and were fabricated using MBE by stacking closely the Stranski-Krastanov (SK) dot in growth direction with monolayer-thick intermediate layers. Uniformity was improved comparing to the single SK dots. The dot laser with cleaved facets operated at the threshold current of 31 mA at room temperature with current density of 250 A/cm/sup 2/ per a single dot layer.