Performance analysis on semiconductor laser amplifier loop mirrors

Operating characteristics of the semiconductor laser amplifier loop mirror (SLALOM) in optical time-division multiplexing (OTDM) applications are investigated in theory. The injection current of the semiconductor laser amplifier (SLA) should be adjusted to realize a flat and high switching window. The channel crosstalk induced by the finite carrier lifetime and the signal timing jitter should be balanced. The optimal switching window width should be slightly wider than half of the OTDM signal bit interval. The control pulse should be narrower than one-third of the OTDM bit interval in order not to deteriorate the bit error rate (BER) performance. Further discussion indicates that the nonlinear gain compression in the SLA becomes a crucial limit for the SLA-based all-optical switches to be used in the terahertz applications.