Dark solitons in ferromagnetic chains with first- and second-neighbor interactions

We study the ferromagnetic spin chain with both first- and second-neighbor interactions. We obtained the condition for the appearance and stability of bright and dark solitons for arbitrary wave number inside the Brillouin zone. The influence of the second-neighbor interaction and the anisotropy on the soliton properties is considered. The scattering of dark solitons from point defects in the discrete spin chain is investigated numerically.Comment: 7 pages,5 figure

Solitary waves for linearly coupled nonlinear Schrodinger equations with inhomogeneous coefficients

Motivated by the study of matter waves in Bose-Einstein condensates and coupled nonlinear optical systems, we study a system of two coupled nonlinear Schrodinger equations with inhomogeneous parameters, including a linear coupling. For that system we prove the existence of two different kinds of homoclinic solutions to the origin describing solitary waves of physical relevance. We use a Krasnoselskii fixed point theorem together with a suitable compactness criterion.Comment: 16 page

Soliton excitations in deformable solids

SIGLEITItal

Exciton solitary waves in molecular crystals

SIGLEITItal

Solitary exicitations in gyrotropic crystals

SIGLEITItal