Institut für Theoretische Physik, Goethe-Universität Frankfurt, 60438 Frankfurt/Main, Germany.
Institut für Theoretische Physik, Goethe-Universität Frankfurt, 60438 Frankfurt/Main, Germany and I. Institut für Theoretische Physik, Universität Hamburg, 20355 Hamburg, Germany.
Phys Rev Lett. 2013 Feb 15;110(7):075302. doi: 10.1103/PhysRevLett.110.075302. Epub 2013 Feb 12.
We theoretically investigate the thermodynamics of an interacting inhomogeneous two-component Fermi gas in an optical lattice. Motivated by a recent experiment by L. Hackermüller et al., Science 327, 1621 (2010), we study the effect of the interplay between thermodynamics and strong correlations on the size of the fermionic cloud. We use dynamical mean-field theory to compute the cloud size, which in the experiment shows an anomalous expansion behavior upon increasing attractive interaction. We confirm this qualitative effect but, assuming adiabaticity, we find quantitative agreement only for weak interactions. For strong interactions we observe significant nonequilibrium effects which we attribute to a dynamical arrest of the particles due to increasing correlations.
我们从理论上研究了光学晶格中相互作用的非均匀双组分费米气体的热力学性质。受 L. Hackermüller 等人最近的实验的启发，我们研究了热力学和强关联之间的相互作用对费米云大小的影响。我们使用动态平均场理论来计算云的大小，在实验中，随着吸引力相互作用的增加，云的大小表现出异常的膨胀行为。我们证实了这一定性效应，但假设绝热性，我们只在弱相互作用下发现了定量的一致性。对于强相互作用，我们观察到显著的非平衡效应，我们将其归因于由于相关性的增加导致粒子的动力学捕获。
