Abstract

The mutual trapping between the two polarization components through cross-phase modulation in a birefringent fiber is a well-known phenomenon. The cross-phase modulation shifts the frequencies of both components and reduces the relative speed between them. When both modes in a dual-mode fiber are excited by a pulsed signal, the effect of cross-phase modulation between the two modes is weak because the relative group velocity between the two modes is large. However, when two pulsed signals of different central frequencies are launched into the same dual-mode fiber, the relative group velocity between the first-order mode of one signal and the second-order mode of the other signal can be small, so that the effect of cross-phase modulation is prominent. This fact provides a chance for studying the dependence of cross-phase modulation on the transverse profiles of the modes. In this research, a set of coupled nonlinear Schrodinger equations is derived for the two modes of two different frequencies in a dual-mode fiber. These equations include overlapping integrals to account for the Kerr effect. The set of equations is solved by means of the beam-propagation method to observe the effects of cross-phase modulation.

© 1990 Optical Society of America