Soliton dynamics in an extended nonlinear Schrodinger equation with a spatial counterpart of the stimulated Raman scattering

• Main Authors: Gromov, E. M, Malomed, B. A
• Format: Journal Article
• Language: English
• Published: 19-06-2013
• Subjects: Physics - Pattern Formation and Solitons
• DOI: 10.48550/arxiv.1306.4550

Dynamics of solitons is considered in the framework of the extended nonlinear
Schrodinger equation (NLSE), which is derived from a system of Zakharov's type
for the interaction between high- and low-frequency (HF and LF) waves, in which
the LF field is subject to diffusive damping. The model may apply to the
propagation of HF waves in plasmas. The resulting NLSE includes a
pseudo-stimulated-Raman-scattering (PSRS) term, i.e., a spatial-domain
counterpart of the SRS term which is well known as an ingredient of the
temporal-domain NLSE in optics. Also included is inhomogeneity of the spatial
second-order diffraction (SOD). It is shown that the wavenumber downshift of
solitons, caused by the PSRS, may be compensated by an upshift provided by the
SOD whose coefficient is a linear function of the coordinate. An analytical
solution for solitons is obtained in an approximate form. Analytical and
numerical results agree well, including the predicted balance between the PSRS
and the linearly inhomogeneous SOD.