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arXiv · 1604.06969

Observation of Quantum Equilibration in Dilute Bose Gases

Linxiao Niu·Pengju Tang·Baoguo Yang·Xuzong Chen·Biao Wu·Xiaoji Zhou
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Abstract

We investigate experimentally the dynamical relaxation of a non-integrable quantum many-body system to its equilibrium state. A Bose-Einstein condensate is loaded into the first excited band of an optical lattice and let to evolve up to a few hundreds of milliseconds. Signs of quantum equilibration are observed. There is a period of time, roughly 40 ms long, during which both the aspect ratio of the cloud and its momentum distribution remain constant. In particular, the momentum distribution has a flat top and is not a Gaussian thermal distribution. After this period, the cloud becomes classical as its momentum distribution becomes Gaussian.

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Linxiao Niu, Pengju Tang, Baoguo Yang, Xuzong Chen, Biao Wu, Xiaoji Zhou. 2016-07-06. Observation of Quantum Equilibration in Dilute Bose Gases. https://doi.org/10.1103/physreva.94.063603

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