All-optical and logic gate based on semiconductor optical amplifiers for implementing deep recurrent neural networks

The development of optical logic gates is a key factor for enabling next generation of computations in the context of Deep Learning and Quantum Computing. In this work, we introduce a scheme for the implementation of an alloptical AND logic gate, which makes use of semiconductor optical amplifiers (SOA) in cross-phase modulation configuration combined with an all-optical XOR gate. Our analysis includes a realistic model of SOA, which considers also the phase and the delay of the signals. We prove that our scheme allows us to obtain almost ideal transitions in 3 out of the 4 situations in a 2-bit logic, with any SOA. The remaining combination shows a reduction of extinction ratio, which can still be improved with better tuning of SOAs.