(Invited) High Performance Quantum Dot Microtube Lasers and Nanowire LEDs on Si

Abstract

We report on the recent achievements of rolled-up InGaAs/GaAs quantum dot microtube lasers as well as high efficiency InGaN/GaN dot-in-a-wire nanoscale heterostructures on Si. Free-standing rolled-up microtube ring resonators are formed by controlled release of coherently strained InGaAs/GaAs quantum dot heterostructures from the host substrate. We have demonstrated optically pumped rolled-up microtube lasers, which exhibit emission wavelengths in the range of 1.1 - 1.3 μm and a low threshold of ~ 4 μW at room temperature. For applications in solid state lighting, we have further developed nearly defect-free, vertically aligned InGaN/GaN dot-in-a-wire nanoscale heterostructures on Si(111) substrates. Strong green, yellow, and amber emission, with an internal quantum efficiency of ~ 45% was achieved.