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arXiv · 1401.4890

Damped solitons in an extended nonlinear Schrodinger equation with a spatial stimulated Raman scattering and decreasing dispersion

Abstract

Dynamics of solitons is considered in the framework of an extended nonlinear Schrodinger equation (NLSE), which is derived from a system of the Zakharov's type for the interaction between high- and low-frequency (HF and LF) waves. The resulting NLSE includes a pseudo-stimulated-Raman-scattering (pseudo-SRS) term, i.e., a spatial-domain counterpart of the SRS term, which is a known ingredient of the temporal-domain NLSE in optics. Also included is inhomogeneity of the spatial second-order dispersion (SOD) and linear losses of HF waves. It is shown that wavenumber downshift by the pseudo-SRS may be compensated by upshift provided by SOD whose local strength is an exponentially decaying function of the coordinate. An analytical soliton solution with a permanent shape is found in an approximate form, and is verified by comparison with numerical results

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E. M. Gromov, B. A. Malomed. 2014-01-20. Damped solitons in an extended nonlinear Schrodinger equation with a spatial stimulated Raman scattering and decreasing dispersion. https://doi.org/10.1016/j.optcom.2014.01.050

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