Binary matter-wave compactons induced by inter-species scattering length modulations
arXiv:1801.00135 · doi:10.1088/1361-6455/aa7dd5
Abstract
Binary mixtures of quasi one-dimensional Bose-Einstein condensates (BEC) trapped in deep optical lattices (OL) in the presence of periodic time modulations of the inter-species scattering length, are investigated. We adopt a mean field description and use the tight binding approximation and the averaging method to derive averaged model equations in the form of two coupled discrete nonlinear Schrödinger equations (DNLSE) with tunneling constants that nonlinearly depend on the inter-species coupling. We show that for strong and rapid modulations of the inter-species scattering length, the averaged system admits exact compacton solutions, e.g. solutions that have no tails and are fully localized on a compact which are achieved when the densities at the compact edges are in correspondence with zeros of the Bessel function (zero tunneling condition). Deviations from exact conditions give rise to the formation of quasi-compactons, e.g. non exact excitations which look as compactons for any practical purpose, for which the zero tunneling condition is achieved dynamically thanks to an effective nonlinear dispersive coupling induced by the scattering length modulation. Stability properties of compactons and quasi-compactons are investigated by linear analysis and by numerical integrations of the averaged system, respectively, and results compared with those from the original (unaveraged) system. In particular, the occurrence od delocalizing transitions with existence of thresholds in the mean inter-species scattering length is explicitly demonstrated. Under proper management conditions, stationary compactons and quasi-compactons are quite stable and robust excitations that can survive on very long time scale. A parameter design and a possible experimental setting for observation of these excitations are briefly discussed.
20 pages, 10 figures
References in corpus (21)
- Feshbach Resonances in Ultracold Gases
- Discrete Solitons and Breathers with Dilute Bose-Einstein Condensates
- Double species condensate with tunable interspecies interactions
- A two atomic species superfluid
- Nonlinear excitations in arrays of Bose-Einstein condensates
- Degenerate Bose-Bose mixture in a three-dimensional optical lattice
- Wannier functions analysis of the nonlinear Schrödinger equation with a periodic potential
- Floquet engineering of correlated tunneling in the Bose-Hubbard model with ultracold atoms
- Many-Body Coherent Destruction of Tunneling
- Ultracold Lattice Gases with Periodically Modulated Interactions
- Density-Dependent Synthetic Gauge Fields Using Periodically Modulated Interactions
- Exploring Unconventional Hubbard Models with Doubly Modulated Lattice Gases
- Compactons in Nonlinear Schrödinger Lattices with Strong Nonlinearity Management
- Delocalizing transition of multidimensional solitons in Bose-Einstein condensates
- Macroscopic quantum tunneling and resonances in coupled Bose-Einstein condensates with oscillating atomic scattering length
- Compactification tuning for nonlinear localized modes in sawtooth lattices
- Tuning the Quantum Phase Transition of Bosons in Optical Lattices via Periodic Modulation of s-Wave Scattering Length
- Mixed symmetry localized modes and breathers in binary mixtures of Bose-Einstein condensates in optical lattices
- Pulsating and persistent vector solitons in a Bose-Einstein condensate in a lattice upon phase separation instability
- Compacton matter waves in binary Bose gases under strong nonlinear management
- Multidimensional Discrete Compactons in Nonlinear Schrödinger Lattices with Strong Nonlinearity Management