Erbium-doped fiber amplifiers with wavelength-selective optical feedback

An optically-controlled fiber ring laser behaving as a low-speed all-optical inverter was demonstrated. Applications in fault location for lightwave systems, nonlinear optical circuitry and simple logic functions are described. Two inverters using erbium-doped fiber amplifiers were cross-coupled to form an all-optical guided-wave set/reset hip-hop that had greater than 40-dB extinction ratio and a state transition time of 1.6 ms.