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arXiv · 1501.02262

Connecting Berezinskii-Kosterlitz-Thouless and BEC phase transitions by tuning interactions in a trapped gas

Richard J. Fletcher·Martin Robert-de-Saint-Vincent·Jay Man·Nir Navon·Robert P. Smith·Konrad G. H. Viebahn·Zoran Hadzibabic
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Abstract

We study the critical point for the emergence of coherence in a harmonically trapped two-dimensional Bose gas with tuneable interactions. Over a wide range of interaction strengths we find excellent agreement with the classical-field predictions for the critical point of the Berezinskii-Kosterlitz-Thouless (BKT) superfluid transition. This allows us to quantitatively show, without any free parameters, that the interaction-driven BKT transition smoothly converges onto the purely quantum-statistical Bose-Einstein condensation (BEC) transition in the limit of vanishing interactions.

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Richard J. Fletcher, Martin Robert-de-Saint-Vincent, Jay Man, Nir Navon, Robert P. Smith, Konrad G. H. Viebahn, Zoran Hadzibabic. 2015-06-29. Connecting Berezinskii-Kosterlitz-Thouless and BEC phase transitions by tuning interactions in a trapped gas. https://doi.org/10.1103/physrevlett.114.255302

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