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arXiv · 1309.1441

Quantum Joule-Thomson Effect in a Saturated Homogeneous Bose Gas

Tobias F. Schmidutz·Igor Gotlibovych·Alexander L. Gaunt·Robert P. Smith·Nir Navon·Zoran Hadzibabic
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Abstract

We study the thermodynamics of Bose-Einstein condensation in a weakly interacting quasi-homogeneous atomic gas, prepared in an optical-box trap. We characterise the critical point for condensation and observe saturation of the thermal component in a partially condensed cloud, in agreement with Einstein's textbook picture of a purely statistical phase transition. Finally, we observe the quantum Joule-Thomson effect, namely isoenthalpic cooling of an (essentially) ideal gas. In our experiments this cooling occurs spontaneously, due to energy-independent collisions with the background gas in the vacuum chamber. We extract a Joule-Thomson coefficient $μ_{\rm JT} > 10^9$ K/bar, about ten orders of magnitude larger than observed in classical gases.

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Tobias F. Schmidutz, Igor Gotlibovych, Alexander L. Gaunt, Robert P. Smith, Nir Navon, Zoran Hadzibabic. 2014-01-29. Quantum Joule-Thomson Effect in a Saturated Homogeneous Bose Gas. https://doi.org/10.1103/physrevlett.112.040403

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