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The atomic Bose gas in Flatland

Zoran Hadzibabic·Peter Krüger·Marc Cheneau·Baptiste Battelier·Jean B. Dalibard
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Abstract

We describe a recent experiment performed with rubidium atoms ($^{87}$Rb), aiming at studying the coherence properties of a two-dimensional gas of bosonic particles at low temperature. We have observed in particular a Berezinskii--Kosterlitz--Thouless (BKT) type crossover in the system, using a matter wave heterodyning technique. At low temperatures, the gas is quasi-coherent on the length scale set by the system size. As the temperature is increased, the loss of long-range coherence coincides with the onset of the proliferation of free vortices, in agreement with the microscopic BKT theory.

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Zoran Hadzibabic, Peter Krüger, Marc Cheneau, Baptiste Battelier, Jean B. Dalibard. 2006-09-29. The atomic Bose gas in Flatland. https://doi.org/10.1063/1.2400645

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