SOLITON STABILITY IN BIREFRINGENT OPTICAL FIBERS - ANALYTICAL APPROACH

Propagation of short pulses in birefringent optical fibers is considered in the framework of two coupled nonlinear Schr8dinger equations. When the amplitudes of the pulses belonging to different polarizations are equal, we propose a simple analytical explanation of the amplitude threshold for the capture of two partial pulses into a coupled two-component pulse. Our approach is based on a soliton phenomenology. The analytical dependence of the amplitude threshold on linear birefringence is in good agreement with numerical results of Menyuk [J. Opt. Soc. Am. B 5, 392 (1988)]. The influence of small dissipative losses on the effect is also discussed. © 1990 Optical Society of America.