A Novel Design for Single-Wavelength All-Optical Flip-Flop Employing Two Coupled SOA-MZIs

In this paper, a novel architecture for a set-reset alloptical flip-flop (SR-AOFF) is proposed. The SR-AOFF operates at a single wavelength causing the ability of cascadingsequenced optical flip-flops. It is based on two coupled semiconductor optical amplifier-Mach Zehnder Interferometer (SOA-MZI) using a common bidirectional coupler. Because ofself phase modulation (SPM) and self gain modulation (SGM) in SOAs, two SOA-MZI switches modulate the injected photonrate of each other. Cross photon rate injection rapidly changes the output states and making optical bistabilty. According tosimulation results, narrow Gaussian pulses with tFWHM 15 ps and 6.8 fJ of optical energy can switch the SR-AOFF. Also simulation results show that the SR-AOFF has extinction ratio of 8.6dB between two states with the transition time of nearly 95ps.