NONLINEAR-OPTICAL LOOP MIRROR DEMULTIPLEXER USING A RANDOM BIREFRINGENCE FIBER - COMPARISONS BETWEEN SIMULATIONS AND EXPERIMENTS

A numerical simulation of the switching characteristics of a polarizat ion multiplexed nonlinear-optical loop mirror demultiplexer is present ed and compared with experiment. The model assumes that the optical fi ber that composes the loop has a randomly varying birefringence, that the signal and the control pulses have the same frequency, and that th ese pulses are nearly solitons. Factors that affect the shape and the width of the switching window curve are discussed. A phase-dependent m odulation of the switching window curve, which is due to incomplete av eraging of the light polarization state, is observed both experimental ly and numerically. Models in which the randomness is neglected are no t able to describe this modulation adequately. (C) 1997 Optical Societ y of America.