Quantum well lasers for microwave/millimeter wave applications

Summary form only given. Developments in high-speed semiconductor lasers have made possible the practical realization of optical/microwave systems as exemplified by applications such as antenna remoting, delay lines, and optically steerable phased-array antennas, to name a few. Present-day laser diodes can attain direct modulation bandwidths of up to 20 GHz. To advance into the higher-frequency and millimeter-wave range, lasers incorporating quantum-well structures should be used. This structure is largely if not solely responsible for recent advances in obtaining ultralow lasing threshold (0.5 mA), ultrahigh modulation speed (30 GHz), and ultrahigh AM and FM modulation efficiency. Recent theoretical predictions and experimental demonstrations also showed that appropriately designed single-quantum-well lasers can be made to mode-lock at millimeter-wave frequencies of 100 GHz or higher. Furthermore, the introduction of strained-layer quantum-well structures has furthered these goals. They will have significant implications not only in the establishment of optical techniques in microwave and radar systems, but also in computer optical interconnects and in telecommunications.<>