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arXiv · 1505.08152

Probing the Excitations of a Lieb-Liniger Gas from Weak to Strong Coupling

Florian Meinert·Milosz Panfil·Manfred J. Mark·Katharina Lauber·Jean-Sébastien Caux·Hanns-Christoph Nägerl
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Abstract

We probe the excitation spectrum of an ultracold one-dimensional Bose gas of Cesium atoms with repulsive contact interaction that we tune from the weakly to the strongly interacting regime via a magnetic Feshbach resonance. The dynamical structure factor, experimentally obtained using Bragg spectroscopy, is compared to integrability-based calculations valid at arbitrary interactions and finite temperatures. Our results unequivocally underly the fact that hole-like excitations, which have no counterpart in higher dimensions, actively shape the dynamical response of the gas.

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Florian Meinert, Milosz Panfil, Manfred J. Mark, Katharina Lauber, Jean-Sébastien Caux, Hanns-Christoph Nägerl. 2015-05-29. Probing the Excitations of a Lieb-Liniger Gas from Weak to Strong Coupling. https://doi.org/10.1103/physrevlett.115.085301

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