Parametric amplification and modulational instabilities in dispersive nonlinear directional couplers with relaxing nonlinearity
Authors: Trillo S., Wabnitz S., Stegeman G.I., Wright E.M.
Autors Affiliation: Fondazione Ugo Bordoni, Italy; Optical Sciences Center, University of Arizona, Tucson, AZ, 85721, United States
Abstract: We investigate the effects of a nonlinearity with a finite response time, combined with group-velocity dispersion and self-phase modulation, on the parametric amplification and modulational instability exhibited by light propagating in a nonlinear directional coupler. A linear-stability analysis of the nonlinear coupled-mode equations describing propagation in the coupler furnishes simple general expressions for the bandwidth of the spatial growth rate of an initially weak modulation for the case in which the carrier propagates in either the symmetric or the antisymmetric mode of the coupler. New types of scalar and vectorial modulational instabilities of the nonlinear Schrodinger equation are predicted, in both the normal- and the anomalous-dispersion regimes. The physical origin of these instabilities is the interplay among linear coupling, parametric four-photon mixing, and Raman scattering.
Journal/Review: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B: OPTICAL PHYSICS
Volume: 6 (5) Pages from: 889 to: 900
KeyWords: InstabilityDOI: 10.1364/JOSAB.6.000889Citations: 74data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2023-09-24References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here