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arXiv · 0704.1439

Critical Behavior of a Trapped Interacting Bose Gas

Tobias Donner·Stephan Ritter·Thomas Bourdel·Anton Öttl·Michael Köhl·Tilman Esslinger
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Abstract

The phase transition of Bose-Einstein condensation is studied in the critical regime, when fluctuations extend far beyond the length scale of thermal de Broglie waves. Using matter-wave interference we measure the correlation length of these critical fluctuations as a function of temperature. The diverging behavior of the correlation length above the critical temperature is observed, from which we determine the critical exponent of the correlation length for a trapped, weakly interacting Bose gas to be $ν=0.67\pm 0.13$. This measurement has direct implications for the understanding of second order phase transitions.

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Tobias Donner, Stephan Ritter, Thomas Bourdel, Anton Öttl, Michael Köhl, Tilman Esslinger. 2007-04-11. Critical Behavior of a Trapped Interacting Bose Gas. https://doi.org/10.1126/science.1138807

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