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arXiv · 0809.2216

Matter-wave dark solitons in a double-well potential

Ryoko Ichihara·Ippei Danshita·Tetsuro Nikuni
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Abstract

We study stability of the first excited state of quasi-one-dimensional Bose-Einstein condensates in a double-well potential, which is called "$π$-state". The density notch in the $π$-state can be regarded as a standing dark soliton. From the excitation spectrum, we determine the critical barrier height, above which the $π$-state is dynamically unstable. We find that the critical barrier height decreases monotonically as the number of condensate atoms increases. We also simulate the dynamics of the $π$-state by solving the time-dependent Gross-Pitaevskii equation. We show that due to the dynamical instability the dark soliton starts to move away from the trap center and exhibits a large-amplitude oscillation.

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Ryoko Ichihara, Ippei Danshita, Tetsuro Nikuni. 2008-09-12. Matter-wave dark solitons in a double-well potential. https://doi.org/10.1103/physreva.78.063604

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