We propose a simple way to generate nonlinear excitations in a controllable way by managing interactions in Bose-Einstein condensates. Under the action of a quantum analog of a classical piston, the condensed atoms are pushed through the trap, generating vortex rings infully three-dimensional condensates or soliton trains in quasi-one-dimensional scenarios. The vortex rings form due to transverse instability of the shock-wave train, enhanced and supported by the energy transfer between waves. We elucidate in what sense the self-interactions within the atom cloud define the properties of the generated vortex rings and soliton trains. Based on the quantum-piston scheme we study the behavior of two-component Bose-Einstein condensates and analyze how the presence of an additional superfluid influences the generation of vortex rings or solitons in the other component, and vice versa. Finally, we show the dynamical emergence of skyrmions within two-component systems in the immiscible regime. © 2013 American Physical Society.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: F.P. was partly supported by EPSRC and a KAUST grant and his work was carried out at the Cambridge Center for Analysis (CCA). N.G.B. acknowledges support from Grant No. FP7 CLERMONT4 PITNGA-2009235114. V. M. P.-G. is partially supported by Grant No. MTM2012-31073 (Ministerio de Economia y Competitividad, Spain).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.