Realization of all-optical circular shift register using semiconductor optical amplifiers

An all-optical circular shifting register based on the cross-gain modulation of a semiconductor optical amplifier (SOA), a key component for future optical computers and signal processing, is experimentally demonstrated. The ideal schemes of left and right circular shifting registers are proposed. On the basis of the scheme, a left circular shifting register that can shift up to three times has been experimentally demonstrated using two SOAs and verified by VPI simulation.