量子牛顿摆中时标的分离

具有玻色-爱因斯坦凝聚体的牛顿摆模拟

Newton's cradle analogue with Bose-Einstein condensates

我们提出了一个可能的实验实现的量子模拟牛顿摇篮使用的配置，从玻色-爱因斯坦凝聚体开始。该系统由两个原子组成，原子被囚禁在具有纵向光晶格的一维管中，并在最大填充时保持在强Tonks-Girardeau区。在每一个站点的波函数是一个叠加的两个原子的状态和扰动的波函数沿链传播类似于在经典的牛顿摆动量的传播。量子行进信号通常被色散劣化，色散对于均匀链是大的，并且对于适当设计的链已知为零，但是后者在实践中几乎不可实现。从这些相反的情况开始，我们展示了如何用最少的实验努力来增强连贯的行为。

Thermalization of a quantum Newton's cradle in a one-dimensional quasicondensate

We study the nonequilibrium dynamics of the quantum Newton's cradle in a one-dimensional (1D) Bose gas in the weakly-interacting quasicondensate regime. This is the opposite regime to the original quantum Newton's cradle experiment of Kinoshita et al. [Nature 440, 900 (2006)], which was realized in the strongly interacting 1D Bose gas. Using finite temperature c-field methods, we calculate the characteristic relaxation rates to the final equilibrium state. Hence, we identify the different dynamical regimes of the system in the parameter space that characterizes the strength of interatomic inte…

Hydrodynamics of the interacting Bose gas in the Quantum Newton Cradle setup

Describing and understanding the motion of quantum gases out of equilibrium is one of the most important modern challenges for theorists. In the groundbreaking Quantum Newton Cradle experiment [Kinoshita, Wenger and Weiss, Nature 440, 900, 2006], quasi-one-dimensional cold atom gases were observed with unprecedented accuracy, providing impetus for many developments on the effects of low dimensionality in out-of-equilibrium physics. But it is only recently that the theory of generalized hydrodynamics has provided the adequate tools for a numerically efficient description. Using it, we give a co…

Thermalization near integrability in a dipolar quantum Newton's cradle

Isolated quantum many-body systems with integrable dynamics generically do not thermalize when taken far from equilibrium. As one perturbs such systems away from the integrable point, thermalization sets in, but the nature of the crossover from integrable to thermalizing behavior is an unresolved and actively discussed question. We explore this question by studying the dynamics of the momentum distribution function in a dipolar quantum Newton's cradle consisting of highly magnetic dysprosium atoms. This is accomplished by creating the first one-dimensional Bose gas with strong magnetic dipole-…

Dynamics of trapped one-dimensional bosons for intermediate repulsive interactions

The time-evolution of few number of interacting, harmonically confined one-dimensional bosons is numerically obtained for arbitrary two-body $δ-$potential interaction strengths. It is demonstrated that the period of the motion in a Newton's cradle configuration undergoes two crossovers as a function of interactions. Furthermore, through the evaluation of the structure factor, the dependence of Bragg-scattering peaks on the interaction strength ranging from the weak coupling regime to the impenetrable Tonks-Girardeau case is illustrated.

Energy-dependent 3-body loss in 1D Bose gases

We study the loss of atoms in quantum Newton's cradles (QNCs) with a range of average energies and transverse confinements. We find that the three-body collision rate in one-dimension is strongly energy dependent, as predicted by a strictly 1D theory. We adapt the theory to atoms in waveguides, then using detailed momentum measurements to infer all the collisions that occur, we compare the observed loss to the adapted theory and find that they agree well.