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arXiv · 1803.06338

Elliptic flow in a strongly-interacting normal Bose gas

Richard J. Fletcher·Jay Man·Raphael Lopes·Panagiotis Christodoulou·Julian Schmitt·Maximilian Sohmen·Nir Navon·Robert P. Smith·Zoran Hadzibabic
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Abstract

We study the anisotropic, elliptic expansion of a thermal atomic Bose gas released from an anisotropic trapping potential, for a wide range of interaction strengths across a Feshbach resonance. We show that in our system this hydrodynamic phenomenon is for all interaction strengths fully described by a microscopic kinetic model with no free parameters. The success of this description crucially relies on taking into account the reduced thermalising power of elastic collisions in a strongly interacting gas, for which we derive an analytical theory. We also perform time-resolved measurements that directly reveal the dynamics of the energy transfer between the different expansion axes.

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Richard J. Fletcher, Jay Man, Raphael Lopes, Panagiotis Christodoulou, Julian Schmitt, Maximilian Sohmen, Nir Navon, Robert P. Smith, Zoran Hadzibabic. 2018-03-16. Elliptic flow in a strongly-interacting normal Bose gas. https://doi.org/10.1103/physreva.98.011601

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