Aycock Lauren M, Hurst Hilary M, Efimkin Dmitry K, Genkina Dina, Lu Hsin-I, Galitski Victor M, Spielman I B
Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, Gaithersburg, MD, 20899.
Department of Physics, Cornell University, Ithaca, NY 14850.
Proc Natl Acad Sci U S A. 2017 Mar 7;114(10):2503-2508. doi: 10.1073/pnas.1615004114. Epub 2017 Feb 14.
We observed and controlled the Brownian motion of solitons. We launched solitonic excitations in highly elongated [Formula: see text] Bose-Einstein condensates (BECs) and showed that a dilute background of impurity atoms in a different internal state dramatically affects the soliton. With no impurities and in one dimension (1D), these solitons would have an infinite lifetime, a consequence of integrability. In our experiment, the added impurities scatter off the much larger soliton, contributing to its Brownian motion and decreasing its lifetime. We describe the soliton's diffusive behavior using a quasi-1D scattering theory of impurity atoms interacting with a soliton, giving diffusion coefficients consistent with experiment.
我们观测并控制了孤子的布朗运动。我们在高度拉长的[公式：见原文]玻色 - 爱因斯坦凝聚体（BECs）中激发孤子，并表明处于不同内态的杂质原子的稀薄背景会显著影响孤子。在没有杂质且处于一维（1D）情况下，这些孤子将具有无限长的寿命，这是可积性的结果。在我们的实验中，添加的杂质与大得多的孤子发生散射，导致其布朗运动并缩短其寿命。我们使用杂质原子与孤子相互作用的准一维散射理论来描述孤子的扩散行为，得出与实验一致的扩散系数。
