Wavelength converters using semiconductor optical amplifiers and its small signal analysis

A new type all-optical device, wavelength converter, was mainly discussed. Its principle has been analyzed physically, small signal analysis has been made theoretically. Useful conclusion has been obtained, an analytic expression was developed. The conclusion is that while two light beams enter the semiconductor optical amplifier simultaneously if one of them has some changes, the other light beam will be modulated. The changes only indicate the differences of its phase and amplitude.