Multi-state Optical Flip-flop Memory Based on Cascaded Lasers

A multi-state optical flip-flop memory based on cascaded lasers is presented. We show that only one of the lasers can lase at a time, thus the state of the optical memory is determined by the wavelength of the dominant laser. The light from the dominant laser suppresses its neighboring lasers through gain saturation, but still receives amplification by the active element of the suppressed lasers, compensating for coupling losses. This light passes through each of the successive lasers, simultaneously suppressing and being amplified, thus all other lasers are suppressed. A five-state optical memory based on this concept is experimentally demonstrated