Quantum Fermi-Pasta-Ulam recurrence in ultracold atomic gases

Fermi-Pasta-Ulam递推是非线性物理学的基础，对FPU递推的理解导致了“孤子”的发现和混沌理论的发展。然而，FPU复发的实验观察是非常罕见的。在这项工作中，我们提出了在将一维玻色气体限制在光学晶格中的实验中可以实际观察到FPU递推。此外，我们还表明，强量子涨落对FPU振荡有显著的阻尼作用。

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.