Simultaneous All-Optical and and nor Gates for NRZ Differential Phase-Shift-Keying Signals

A scheme for realizing all-optical logic AND and NOR gates simultaneously for nonreturn-to-zero differential phase-shift-keying signals is proposed and demonstrated based on a delayed interferometer and two semiconductor optical amplifiers. Experimental demonstration at 20 Gb/s verifies the logic integrity of this scheme. The final results are derived in the ON-OFF keying format with clear open eyes and extinction ratios over 10 dB. The proposed scheme can be expanded to realize arbitrary logic gate.