Semiconductor laser amplifiers for ultrafast all-optical signal processing

Recent progress in the use of semiconductor laser amplifiers (SLA's) for high-speed all-optical switching is reviewed. We show that, despite SLA's having lifetimes of ⩾100 ps, they are, to date, the most promising material system for all-optical ultrafast signal processing. We highlight the role of SLA carrier dynamics, which permits switching rates faster than the recovery time. Experimental results are presented that imply that switching rates of as much as ∼100 GHz should be possible. Recent experiments are described in which SLA-based switches were incorporated into novel all-optical architectures.