Raman peak shifts due to walk-off in non-instantaneous Kerr media with higher-order effects

Michel-Rostand Soumo Tchio, Saïdou Abdoulkary, and Alidou Mohamadou

• Vol. 36,
• Issue 12,
• pp. 3479-3491
• (2019)
• •https://doi.org/10.1364/JOSAB.36.003479

Abstract

We study analytically and numerically the modulation instability (MI) of two incoherently co-propagating optical pulses in nonlinear fiber, taking into account high-order nonlinearity, walk-off effects, delay response time, and cross-phase modulation in several dispersion regimes. We show that higher-order nonlinearity is responsible for superposition of the secondary MI spectrum. We realize that there is a peak located in the emerged Raman band that we call “Raman peak” due to the combined effects of third-order dispersion, delay response time, and the opposite sign of the fourth-order dispersion parameter. These peaks are shifted toward higher frequencies when the walk-off increases.

© 2019 Optical Society of America