Kh. P. Khamrakulov, Regular and chaotic dynamics of a matter-wave soliton near the atomic mirror, Int. J. Mod. Phys. B28, 1450198 (2014).
The dynamics of the soliton in a self-attractive Bose-Einstein condensate under the gravity are investigated. First, we apply the inverse scattering method, which gives rise to equation of motion for the center-of-mass coordinate of the soliton. We analyze the amplitude-frequency characteristic for nonlinear resonance. Applying the KrylovBogoliubov method for the small parameters the dynamics of soliton on the phase plane are considered. Hamiltonian chaos under the action of the gravity on the Poincar´e map are studied.