Noise suppression characteristics of negative feedback optical amplifier using an optical triode

We demonstrated that an all-optical triode can be achieved by using a tandem wavelength converter employing cross-gain modulation (XGM) in semiconductor optical amplifiers (SOAs). Wavelength conversion and switching characteristics was investigated by introducing a control light together with input signal light. As the optical triode operates by controlling SOA´s gain, a negative feedback (NF) optical amplification effect occurs by injecting the input signal light into the input and control ports. As a result, improvement on extinction ratio, noise suppression and pattern effect was expected. In this report, we investigate about noise suppression characteristic during signal light amplification using optical triode.