Ultrafast all-optical switching using a frequency shift accompanied by cross-phase modulation in a semiconductor optical amplifier

Summary form only given. All-optical switches are quite attractive for optical demultiplexing and for other various optical signal processing in future optical-time-division-multiplexing (OTDM) networks. Optical demultiplexers will likely require switching operation for more than 100-Gbps signals at a-repetition rate of 10-40 GHz with low control-light power. A promising approach for such applications is a transient cross-phase-modulation (T-XPM) all-optical switch, which features not only ultrafast switching with low control-light power but also a quite simple configuration. The simple configuration leads, to many advantages such as compactness, stability, and polarization-insensitivity. In this report, we present ultrafast (corresponding to 168-Gbps demultiplexing) and high-repetition (10 GHz) operations of the T-XPM all-optical switch with a control-pulse energy of less than 1 pJ. These operations have been achieved by using a semiconductor optical amplifier as a nonlinear waveguide and setting the control pulse duration shorter than the signal pulse duration.