Emulating the Raman Physics in the Spatial Domain with the Help of the Zakharov’s Systems

Interplay of the pseudo-Raman term and trapping potentials in the nonlinear Schrödinger equation

“…As shown in Refs. [23][24][25], the latter term, appearing in various settings (see also a short review of previous results in [26]), takes the same form as the well-known stimulated-Raman-scattering (SRS) term in fiber optics [27][28][29], which has an absolutely different physical nature, being induced by the effect of a small delay (~3 fs) of the nonlinear dielectric response of the silica glass on the temporal-domain evolution of optical pulses [1,3]. In terms of the ZS reduced to the single NLSE, the term under the consideration acts in the spatial domain, and it may be naturally called a pseudo-SRS one, there being no real Raman effect in the present setting, while the ZS, which includes the viscosity acting on the LF component, provides effective emulation of optical SRS (note that the SRS terms in optics is a dissipative effect too).…”

“…In addition to driving the self-acceleration of solitons, the SRS may also drive shock waves in fibers [36,37] In the NLSE including the pseudo-SRS term, stabilization of solitons is a relevant issue too. In previous works [23][24][25][26], a solution was proposed which used variable dispersion, which made it possible to provide stable compensation of the detrimental effect induced by pseudo-SRS.…”