Skip to main content
Log in

The concept of quasi-integrability for modified non-linear Schrödinger models

  • Published:
Journal of High Energy Physics Aims and scope Submit manuscript

Abstract

We consider modifications of the nonlinear Schrödinger model (NLS) to look at the recently introduced concept of quasi-integrability. We show that such models possess an infinite number of quasi-conserved charges which present intriguing properties in relation to very specific space-time parity transformations. For the case of two-soliton solutions where the fields are eigenstates of this parity, those charges are asymptotically conserved in the scattering process of the solitons. Even though the charges vary in time their values in the far past and the far future are the same. Such results are obtained through analytical and numerical methods, and employ adaptations of algebraic techniques used in integrable field theories. Our findings may have important consequences on the applications of these models in several areas of non-linear science. We make a detailed numerical study of the modified NLS potential of the form V ~ (|ψ|2)2+ε, with ε being a perturbation parameter. We perform numerical simulations of the scattering of solitons for this model and find a good agreement with the results predicted by the analytical considerations. Our paper shows that the quasi-integrability concepts recently proposed in the context of modifications of the sine-Gordon model remain valid for perturbations of the NLS model.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. N.J. Zabusky and M.D. Kruskal, Interaction ofsolitonsin a collisionless plasma and the recurrence of initial states, Phys. Rev. Lett. 15 (1965) 240 [INSPIRE].

    Article  ADS  MATH  Google Scholar 

  2. E. Fermi, J.R. Pasta and S. Ulam, Studies of non linear problems, Los Alamos Scientific Laboratory Report, Document LA-1940 (1955), unpublished.

  3. P.D. Lax, Integrals of nonlinear equations of evolution and solitary waves, Commun. Pure Appl. Math. 21 (1968) 467 [INSPIRE].

    Article  MathSciNet  MATH  Google Scholar 

  4. V.E. Zakharov and A.B. Shabat, Exact theory of two-dimensional selffocusing and one-dimensional selfmodulation of waves in nonlinear media, Zh. Exp. Teor. Fiz. 61 (1971) 118 [Sov. Phys. JETP 34 (1972) 62] [INSPIRE].

  5. L.D. Faddeev and L.A. Takhtajan, Hamiltonian methods in the theory of solitons, Springer Series in Soviet Mathematics, Springer, Berlin Germany (1987) [INSPIRE].

    MATH  Google Scholar 

  6. O. Babelon, D. Bernard and M. Talon, Introduction to classical integrable systems, Cambridge University Press, Cambridge U.K. (2003).

    Book  MATH  Google Scholar 

  7. L.A. Ferreira and W.J. Zakrzewski, The concept of quasi-integrability: a concrete example, JHEP 05 (2011) 130 [arXiv:1011.2176] [INSPIRE].

    Article  MathSciNet  ADS  Google Scholar 

  8. D. Bazeia, L. Losano, J.M.C. Malbouisson and R. Menezes, Classical behavior of deformed sine-Gordon models, Physica D 237 (2008) 937 [arXiv:0708.1740] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  9. V.G. Drinfeld and V.V. Sokolov, Lie algebras and equations of Korteweg-de Vries type, J. Sov. Math. 30 (1984) 1975 [INSPIRE].

    Article  Google Scholar 

  10. V.G. Drinfeld and V.V. Sokolov, Equations of Korteweg-de Vries type and simple Lie algebras, Sov. Mat. Dokl. 23 (1981) 457.

    Google Scholar 

  11. D.I. Olive and N. Turok, Local conserved densities and zero curvature conditions for Toda lattice field theories, Nucl. Phys. B 257 (1985) 277 [INSPIRE].

    Article  MathSciNet  ADS  Google Scholar 

  12. D.I. Olive and N. Turok, The Toda lattice field theory hierarchies and zero curvature conditions in Kac-Moody algebras, Nucl. Phys. B 265 (1986) 469 [INSPIRE].

    Article  MathSciNet  ADS  Google Scholar 

  13. H. Aratyn, L.A. Ferreira, J.F. Gomes and A.H. Zimerman, The conserved charges and integrability of the conformal affine Toda models, Mod. Phys. Lett. A 9 (1994) 2783 [hep-th/9308086] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  14. L.A. Ferreira and W.J. Zakrzewski, A simple formula for the conserved charges of soliton theories, JHEP 09 (2007) 015 [arXiv:0707.1603] [INSPIRE].

    Article  MathSciNet  ADS  Google Scholar 

  15. B. Luther-Davies and Y.S. Kivshar, Dark optical solitons: physics and applications, Phys. Rept. 298 (1998) 81.

    Article  ADS  Google Scholar 

  16. G.P. Agrawal, Nonlinear fiber optics: quantum electronicsprinciples and applications, Academic Press (1989).

  17. C. Sulem and P.-L. Sulem, The nonlinear Schrödinger equation: self-focusing and wave collapse, Springer-Verlag (1999).

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to L. A. Ferreira.

Additional information

ArXiv ePrint: 1206.5808

Rights and permissions

Reprints and permissions

About this article

Cite this article

Ferreira, L.A., Luchini, G. & Zakrzewski, W.J. The concept of quasi-integrability for modified non-linear Schrödinger models. J. High Energ. Phys. 2012, 103 (2012). https://doi.org/10.1007/JHEP09(2012)103

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/JHEP09(2012)103

Keywords

Navigation