Quantum Fermi-Pasta-Ulam recurrence in ultracold atomic gases

费米-帕斯塔-乌兰(Fermi-Pasta-Ulam)递推一直是非线性物理的基础，因为对浮子递推的理解导致了“孤子”的发现和混沌理论的发展。然而，对FPU复发的实验观察非常罕见。在这项工作中，我们提出，在一维玻色气体被限制在光学晶格中的实验中，可以实际观察到浮点单位的重现。此外，我们还发现，强烈的量子涨落会对浮点单元的振荡产生显著的衰减。

The Fermi-Pasta-Ulam recurrence has been a foundation of the nonlinear physics in the sense that the pursuit of the understanding of the FPU recurrence led to the discovery of "solitons" and the development of chaos theory. Nevertheless, experimental observation of the FPU recurrence is very rare. In this work, we proposed that the FPU recurrence can be actually observed in experiments with one-dimensional Bose gases confined into an optical lattice. Moreover, we showed that strong quantum fluctuations cause significant damping of the FPU oscillation.