1.3 μm lasers with AlInAs-capped self-assembled quantum dots

We report 1.3 μm room-temperature lasing for a self-assembled quantum dot (QD) laser in which the dots are capped by a thin AlInAs layer. The inclusion of the Al-containing layer is shown to improve the dot uniformity, and the larger carrier confinement increases the separation between the QD transitions. A RT threshold current density of 80 A cm−2 is obtained for a device containing three QD layers. The inclusion of the AlInAs layer allows the modification of the dot physical structure and electronic structure of the device, without any significant incorporation of nonradiative centers.