5 research outputs found
Soliton dynamics at an interface between uniform medium and nonlinear optical lattice
We study trapping and propagation of a matter-wave soliton through the
interface between uniform medium and a nonlinear optical lattice (NOL).
Different regimes for transmission of a broad and a narrow soliton are
investigated. Reflections and transmissions of solitons are predicted as
function of the lattice phase. The existence of a threshold in the amplitude of
the nonlinear optical lattice, separating the transmission and reflection
regimes, is verified. The localized nonlinear surface state, corresponding to
the soliton trapped by the interface, is found. Variational approach
predictions are confirmed by numerical simulations for the original
Gross-Pitaevskii equation with nonlinear periodic potentials
Resonances in a trapped 3D Bose-Einstein condensate under periodically varying atomic scattering length
Nonlinear oscillations of a 3D radial symmetric Bose-Einstein condensate
under periodic variation in time of the atomic scattering length have been
studied analytically and numerically. The time-dependent variational approach
is used for the analysis of the characteristics of nonlinear resonances in the
oscillations of the condensate. The bistability in oscillations of the BEC
width is invistigated. The dependence of the BEC collapse threshold on the
drive amplitude and parameters of the condensate and trap is found. Predictions
of the theory are confirmed by numerical simulations of the full
Gross-Pitaevski equation.Comment: 17 pages, 10 figures, submitted to Journal of Physics