Design of all-optical shift registers using D flip flop based on semiconductor optical amplifiers at 100 Gb/s

Abstract In this communication, we propose and realize all-optical shift registers capable of transferring the input information bits to the output either in serial or in parallel configuration as per the transitions of the clock signal. All-optical D flip flop (DFF) using cross gain modulation (XGM) effect in cross-coupled semiconductor optical amplifiers (SOAs) and an optical NOT gate has been utilized in cascaded configuration to implement the shift registers. The performance of the devices has been investigated in terms of amplitude modulation, contrast ratio and extinction ratio verifying its operation at 100 Gb/s. Reduced complexity and footprint makes the proposed device ideal for photonic integration.