Ultrafast optical time demultiplexers using semiconductor optical amplifiers

The operating principle of the utilization of resonant optical nonlinearities in recently demonstrated ultra-fast all-optical interferometric switching devices is presented. Optimum switching windows expected from these devices are investigated with a simple theoretical analysis. The experimental results of these devices are presented along with the nonlinear optical properties of a semiconductor optical amplifier. The information from the experimental results of the nonlinear optical properties are used to address a problem associated with a saturation of the semiconductor optical amplifier by an incoming ultra-high bit rate data stream. We also discuss the advantages and disadvantages in different operation modes — same or different wavelengths for the control and data signals. Finally, we discuss the relative advantages and disadvantages among these devices.