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arXiv · 1301.1715

Solitary Matter Waves in Combined Linear and Nonlinear Potentials: Detection, Stability, and Dynamics

Scott Holmes·Mason A. Porter·Peter Krüger·Panayotis G. Kevrekidis
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Abstract

We study statically homogeneous Bose-Einstein condensates with spatially inhomogeneous interactions and outline an experimental realization of compensating linear and nonlinear potentials that can yield constant-density solutions. We illustrate how the presence of a step in the nonlinearity coefficient can only be revealed dynamically and consider, in particular, how to reveal it by exploiting the inhomogeneity of the sound speed with a defect-dragging experiment. We conduct computational experiments and observe the spontaneous emergence of dark solitary waves. We use effective-potential theory to perform a detailed analytical investigation of the existence and stability of solitary waves in this setting, and we corroborate these results computationally using a Bogoliubov-de Gennes linear stability analysis. We find that dark solitary waves are unstable for all step widths, whereas bright solitary waves can become stable through a symmetry-breaking bifurcation as one varies the step width. Using phase-plane analysis, we illustrate the scenarios that permit this bifurcation and explore the dynamical outcomes of the interaction between the solitary wave and the step.

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Scott Holmes, Mason A. Porter, Peter Krüger, Panayotis G. Kevrekidis. 2013-09-24. Solitary Matter Waves in Combined Linear and Nonlinear Potentials: Detection, Stability, and Dynamics. https://doi.org/10.1103/physreva.88.033627

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