Two-photon absorption effect on pseudorandom bit sequence for high speed operation

The effect of two-photon absorption (TPA) on all-optical logic operation in quantum-dot semiconductor optical amplifier (QD-SOA) has been carried out. The rate equation was modeled with the TPA effect for the logic XOR gate, AND gate, and, for pseudo-random bit sequence (PRBS) generation. The output Q-factor (quality) has increased due to the implementation of TPA induced pumping. The results show that the quality of the output depends on the input pulse width and the speed of operation. The PRBS system has been shown to operate at 250 Gb/s and 320 Gb/s and the Q-factor decreases with an increase in pulse width.