GaAs-based InAs Quantum Dot Lasers of 1.3 µm Range

Growth of quantum dots (QDs), especially InAs QDs of 1.3 µm range, is intensively studied in Nanophotonics Center, OES-ITRI. High performance edge emitting lasers (EELs) are grown and fabricated for the investigation of their potential in photonics application. Simultaneous ground-state (GS) and excited-state (ES) lasing emissions are observed at higher temperature or at higher driving current. Stacking of multiple QD layers is effective to suppress the ES lasing emissions. Coupled QD stacks with QDs between each layer vertically aligned and electrically coupled are grown and laser emission near 1.24 um is obtained. The spectral width of the coupled QD laser is significantly narrower comparing to the uncoupled case. QD vertical cavity surface emitting lasers (VCSELs) are also successfully fabricated with both the undoped semiconductor DBRs in intracavity-contacted design, and the fully-doped DBRs in conventional direct contact scheme. Optimization of laser performance, the high-speed operation as well as the device reliability are key issues still under investigation.