High Speed All-Photonic Flip-Flop Operation at a Single Wavelength

This work is based on dual Mach-Zehnder interferometer with semiconductor optical amplifiers in both arms. The proposed flip-flop operates at a single wavelength. A bidirectional coupler is placed at the end of the system to observe the output at set and reset terminals. The signals modulate the injected photon rate in the SOAs thus forming photonic flip-flop function. The photon injection rate is modulated due to self-gain modulation and self-phase modulation that occur in the SOAs towards demonstrating optical bistability. Switching between states of the flip-flop occur at full width half maximum of 32 ps. The output power of this flip-flop is around 24.5 mW. It is observed that the switching energy can be adjusted to a low level by decreasing the injected currents into the SOAs. The injection and the input power are the two parameters that govern the whole operation of the designed flip-flop.