Quantum Joule-Thomson effect in a saturated homogeneous Bose gas.
Quantum Joule-Thomson effect in a saturated homogeneous Bose gas.
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饱和均质玻色气体中的量子焦耳-汤姆逊效应。
DOI：
10.1103/physrevlett.112.040403
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发表时间：
2013
影响因子：
8.6
通讯作者：
Z. Hadzibabic
中科院分区：
文献类型：
--
作者：
Tobias F. Schmidutz;Igor Gotlibovych;Alexander L. Gaunt;Robert P. Smith;N. Navon;Z. Hadzibabic
本文研究了在光箱阱中制备的弱相互作用准均匀原子气体中玻色-爱因斯坦凝聚的热力学。我们的特点冷凝的临界点，并观察饱和的热分量在一个部分冷凝的云，在协议与爱因斯坦的教科书图片的一个纯粹的统计相变。最后，我们观察到量子焦耳-汤姆逊效应，即（本质上）理想气体的等熵冷却。在我们的实验中，由于与真空室中的背景气体的能量无关的碰撞，这种冷却自发地发生。我们提取了焦耳-汤姆逊系数μJT>10（9）K/bar，比经典气体中观察到的大约10个数量级。
We study the thermodynamics of Bose-Einstein condensation in a weakly interacting quasihomogeneous atomic gas, prepared in an optical-box trap. We characterize 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 μJT>10(9) K/bar, about 10 orders of magnitude larger than observed in classical gases.