ALL-OPTICAL SAMPLING BASED ON NONLINEAR POLARIZATION ROTATION IN SEMICONDUCTOR OPTICAL AMPLIFIERS

A novel all-optical sampling method based on nonlinear polarization rotation in a semiconductor optical amplifier is proposed. An analog optical signal and an optical clock pulses train are injected into semiconductor optical amplifier simultaneously, and the power of the analog light modulates the intensity of the output optical pulse through controlling the rotated angle of nonlinear polarization rotation of the optical pulse. Therefore, the sampling signals are delivered from the analog light to the optical clock pulses. The simulated results show that the all-optical sampling has good linear slope and large linear dynamic range, and the operating power of the pump light can be less than 1mW. The presented all-optical sampling method can potentially operate at the sampling rate up to hundreds GS/s and needs considerable low optical power, which is suitable for high-speed signal processing.