Instability of Double-Periodic Waves in the Nonlinear Schrödinger Equation

It is shown how to compute the instability rates for the double-periodic solutions to the cubic NLS (nonlinear Schrödinger) equation by using the Lax linear equations. The wave function modulus of the double-periodic solutions is periodic both in space and time coordinates; such solutions generalize...

Full description

Bibliographic Details
Main Author: Dmitry E. Pelinovsky
Format: Article
Language:English
Published: Frontiers Media S.A. 2021-02-01
Series:Frontiers in Physics
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fphy.2021.599146/full
_version_ 1819284273923883008
author Dmitry E. Pelinovsky
author_facet Dmitry E. Pelinovsky
author_sort Dmitry E. Pelinovsky
collection DOAJ
description It is shown how to compute the instability rates for the double-periodic solutions to the cubic NLS (nonlinear Schrödinger) equation by using the Lax linear equations. The wave function modulus of the double-periodic solutions is periodic both in space and time coordinates; such solutions generalize the standing waves which have the time-independent and space-periodic wave function modulus. Similar to other waves in the NLS equation, the double-periodic solutions are spectrally unstable and this instability is related to the bands of the Lax spectrum outside the imaginary axis. A simple numerical method is used to compute the unstable spectrum and to compare the instability rates of the double-periodic solutions with those of the standing periodic waves.
first_indexed 2024-12-24T01:44:46Z
format Article
id doaj.art-ccba69008ae94912a17f7ed7bf39f53b
institution Directory Open Access Journal
issn 2296-424X
language English
last_indexed 2024-12-24T01:44:46Z
publishDate 2021-02-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Physics
spelling doaj.art-ccba69008ae94912a17f7ed7bf39f53b2022-12-21T17:21:54ZengFrontiers Media S.A.Frontiers in Physics2296-424X2021-02-01910.3389/fphy.2021.599146599146Instability of Double-Periodic Waves in the Nonlinear Schrödinger EquationDmitry E. PelinovskyIt is shown how to compute the instability rates for the double-periodic solutions to the cubic NLS (nonlinear Schrödinger) equation by using the Lax linear equations. The wave function modulus of the double-periodic solutions is periodic both in space and time coordinates; such solutions generalize the standing waves which have the time-independent and space-periodic wave function modulus. Similar to other waves in the NLS equation, the double-periodic solutions are spectrally unstable and this instability is related to the bands of the Lax spectrum outside the imaginary axis. A simple numerical method is used to compute the unstable spectrum and to compare the instability rates of the double-periodic solutions with those of the standing periodic waves.https://www.frontiersin.org/articles/10.3389/fphy.2021.599146/fullmodulational instabilitydouble-periodic solutionsFloquet spectrumnonlinear Schrödinger equationstanding waves
spellingShingle Dmitry E. Pelinovsky
Instability of Double-Periodic Waves in the Nonlinear Schrödinger Equation
Frontiers in Physics
modulational instability
double-periodic solutions
Floquet spectrum
nonlinear Schrödinger equation
standing waves
title Instability of Double-Periodic Waves in the Nonlinear Schrödinger Equation
title_full Instability of Double-Periodic Waves in the Nonlinear Schrödinger Equation
title_fullStr Instability of Double-Periodic Waves in the Nonlinear Schrödinger Equation
title_full_unstemmed Instability of Double-Periodic Waves in the Nonlinear Schrödinger Equation
title_short Instability of Double-Periodic Waves in the Nonlinear Schrödinger Equation
title_sort instability of double periodic waves in the nonlinear schrodinger equation
topic modulational instability
double-periodic solutions
Floquet spectrum
nonlinear Schrödinger equation
standing waves
url https://www.frontiersin.org/articles/10.3389/fphy.2021.599146/full
work_keys_str_mv AT dmitryepelinovsky instabilityofdoubleperiodicwavesinthenonlinearschrodingerequation