Performance of all-optical XOR gate based on two-photon absorption in semiconductor optical amplifier-assisted Mach-Zehnder interferometer with effect of amplified spontaneous emission

The performance of all-optical XOR gate is simulated and investigated. This Boolean function is realized by using a Mach-Zehnder interferometer (MZI) and exploiting the nonlinear effect of two-photon absorption (TPA) in semiconductor optical amplifier (SOA) incorporated in the MZI arms. By adjusting the input pulse intensities to be high enough, the TPA-induced phase change can be larger than the regular gain-induced phase change and hence support ultrafast operation in dual rail switching mode. The numerical study is carried out by taking into account the effect of amplified spontaneous emission (ASE). The dependence of the output quality factor (-factor) on critical data signals and SOAs parameters is examined and assessed. The obtained results confirm that the XOR gate implemented with the proposed scheme is capable of operating at a data rate of 250 Gb/s with logical correctness and high output -factor.