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

E. M. Gromov*, B. A. Malomed

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

We introduce a nonlinear Schrödinger equation (NLSE) which combines the pseudo-stimulated-Raman-scattering (pseudo-SRS) term, i.e., a non-conservative cubic one with the first spatial derivative, and an external potential, which helps to stabilize solitons against the pseudo-SRS effect. Dynamics of solitons is addressed by means of analytical and numerical methods. The quasi-particle approximation (QPA) for the solitons demonstrates that the SRS-induced downshift of the soliton's wavenumber may be compensated by a potential force, producing a stable stationary soliton. Three physically relevant potentials are considered: a harmonic-oscillator (HO) trap, a spatially periodic cosinusoidal potential, and the HO trap subjected to periodic temporal modulation. Both equilibrium positions of trapped pulses (solitons) and their regimes of motion with trapped and free trajectories are accurately predicted by the QPA and corroborated by direct simulations of the underlying NLSE. In the case of the time-modulated HO trap, a parametric resonance is demonstrated, in the form of the motion of the driven soliton with an exponentially growing amplitudes of oscillations.

Original languageEnglish
Article number105220
JournalCommunications in Nonlinear Science and Numerical Simulation
Volume85
DOIs
StatePublished - Jun 2020

Funding

FundersFunder number
Israel Science Foundation1287/17

    Keywords

    • Extended nonlinear Schrödinger equation
    • External potential
    • Soliton
    • Spatial stimulated Raman scattering

    Fingerprint

    Dive into the research topics of 'Interplay of the pseudo-Raman term and trapping potentials in the nonlinear Schrödinger equation'. Together they form a unique fingerprint.

    Cite this