Trapping of two-component light bullets in a gradient waveguide with normal group dispersion

In this paper we consider the process of the second harmonic generation in a gradient waveguide, taking into account diffraction and relatively weak temporal dispersion. Using the slowly varying envelope approximation and neglecting the dispersion of the nonlinear part of the response of the medium...

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Published in:PloS one 2019-08, Vol.14 (8), p.e0220840-e0220840
Main Authors: Kalinovich, Aleksey A, Komissarova, Maria V, Sazonov, Sergey V, Zakharova, Irina G
Format: Article
Language:English
Subjects:
Algorithms
Analysis
Applied mathematics
Biology and Life Sciences
Computational mathematics
Computer and Information Sciences
Computer Simulation
Dispersion
Finite difference method
Group velocity
Integrals
Light
Medicine and Health Sciences
Models, Theoretical
Nonlinear response
Numerical Analysis, Computer-Assisted
Optical properties
Optics
Physical Sciences
Physics
Planar waveguides
Projectiles
Propagation
Research and Analysis Methods
Scattering, Radiation
Second harmonic generation
Wave propagation
Waveguides
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description In this paper we consider the process of the second harmonic generation in a gradient waveguide, taking into account diffraction and relatively weak temporal dispersion. Using the slowly varying envelope approximation and neglecting the dispersion of the nonlinear part of the response of the medium we obtain the system of parabolic equations for the envelopes of both harmonics. We also derive integrals of motion of this system. To solve it numerically we construct a nonlinear finite-difference scheme based on the Crank-Nicolson method preserving the integrals. Primarily, we focus our investigations on the processes of a two-component light bullets generation. We demonstrate that the generation of a coupled pair is possible in a planar waveguide even at normal group velocity dispersion.
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subjects Algorithms
Analysis
Applied mathematics
Biology and Life Sciences
Computational mathematics
Computer and Information Sciences
Computer Simulation
Dispersion
Finite difference method
Group velocity
Integrals
Light
Medicine and Health Sciences
Models, Theoretical
Nonlinear response
Numerical Analysis, Computer-Assisted
Optical properties
Optics
Physical Sciences
Physics
Planar waveguides
Projectiles
Propagation
Research and Analysis Methods
Scattering, Radiation
Second harmonic generation
Wave propagation
Waveguides
title Trapping of two-component light bullets in a gradient waveguide with normal group dispersion
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