Nonlinear Energy Exchange between Solitons in Modes of a Silica Few-mode Fiber

Recently soliton propagation in few-mode fiber has been studied. In this paper, we used commercially few-mode fiber for investigating the soliton propagation. Three modes exist in this fiber, by considering polarization, we have six propagation modes. Initially, we calculate the propagation mode, effective cross-section, and dispersion for each mode then soliton propagation in fiber modes with respect to phase are simulated. The nonlinear effect causes XPM which affects propagation modes to each other. By various values of phase, the first maximum energy transfer between modes is calculated. We find minimum normalized length 0.66 which equal to a length of 23.3 meters of silica fiber for energy exchange. The energy exchange can be used as a basis for all-optical switching. Interestingly, these effects cause energy transfer between different modes and strongly depend on the phase difference. So, the results of this simulation can be used to design all-optical self-switches and all optical logic gates.