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arXiv · 1507.04639

Quantum reflection of bright solitary matter-waves from a narrow attractive potential

A. L. Marchant·T. P. Billam·M. M. H. Yu·A. Rakonjac·J. L. Helm·J. Polo·C. Weiss·S. A. Gardiner·S. L. Cornish
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Abstract

We report the observation of quantum reflection from a narrow, attractive, potential using bright solitary matter-waves formed from a 85Rb Bose-Einstein condensate. We create narrow potentials using a tightly focused, red-detuned laser beam, and observe reflection of up to 25% of the atoms, along with the trapping of atoms at the position of the beam. We show that the observed reflected fraction is much larger than theoretical predictions for a narrow Gaussian potential well; a more detailed model of bright soliton propagation, accounting for the generic presence of small subsidiary intensity maxima in the red-detuned beam, suggests that these small intensity maxima are the cause of this enhanced reflection.

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A. L. Marchant, T. P. Billam, M. M. H. Yu, A. Rakonjac, J. L. Helm, J. Polo, C. Weiss, S. A. Gardiner, S. L. Cornish. 2015-07-16. Quantum reflection of bright solitary matter-waves from a narrow attractive potential. https://doi.org/10.1103/physreva.93.021604

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