Multi-Component NLS for Spinor Condensates (Nonlinear Wave Phenomena and Applications)

淳一 家田

淳一 家田

Vladimir Stefanov Gerdjikov, Nikolay A. Kostov, Tihomir Valchev

淳一 家田

Paulsamy Muruganandam, M. Lakshmanan

This chapter focuses on exploring localized excitations in the variable coefficient nonlinear Schrodinger (NLS) equation and its generalizations. The motivation comes from the fact that the NLS equation and its variants appear in several branches/topics of physics, including nonlinear optics and Bose-Einstein condensates (BECs). The chapter reviews critically the variety of matter wave solitons and their interactions in single- and multi-component Bose-Einstein condensates. It provides a brief overview of the mean Gross- Pitaevskii (GP) equation, derivation of the one-dimensional GP equation, and mapping of the 1D GP equation to the standard NLS equation. The chapter discusses matter wave single and multi bright and dark solitons of Bose– Einstein condensates with varying trap potentials and atomic interactions. It shows various solitons solutions of multi-component BECs described by the two coupled GP equations. In this case, the coupled GP equation has been mapped onto a two coupled NLS equation.

Gerdjikov V.S., Nikolay A. Kostov, Valchev T.I.

Three- and five-component nonlinear Schrödinger-type models, which describe spinor Bose-Einstein condensates (BEC's) with hyperfine structures F = 1 and F = 2, respectively, are studied. These models for particular values of the coupling constants are integrable by the inverse scattering method. They are related to symmetric spaces of BD.I-type ≃ SO(2r + 1) / SO(2) × SO(2r -1) for r = 2 and r = 3. Using conveniently modified Zakharov-Shabat dressing procedure we obtain different types of soliton solutions. © 2008 Elsevier B.V. All rights reserved.