Polarization instabilities for solitons in birefringent fibers

We examine the propagation of solitons in the two linearly polarized modes of a birefringent fiber. The behavior of single solitons is similar to that of continuous waves, and the nonlinear effects make the fast mode unstable when the beat length between the modes is long. Even with the instability, nondispersive pulses can still propagate. Highorder solitons break up and can transfer most of the energy into a single, highly compressed soliton.