论文标题
抑制无均匀bose气体自发缺陷形成
Suppression of Spontaneous Defect Formation in Inhomogeneous Bose Gases
论文作者
论文摘要
在涉及对称性破坏的相变动力学中，可以自发产生拓扑缺陷，但由于有序相位信息的扩散，它在空间不均匀的系统中被抑制。我们证明了被困的原子叶气体中的缺陷抑制作用，该原子气体被淬灭到超氟相。在各种淬灭时间测量了创建缺陷的空间分布，并且表明对于较慢的淬火，在样品的外部区域中，自发缺陷的产生相对抑制了较高的原子密度梯度。局部缺陷密度随淬灭时间的幂律缩放在外部区域增强了，这与kibble-zurek机制一致，包括由于系统的空间不均匀性而导致的因果关系。这项工作在使用缺陷位置信息的非平衡相过渡动力学研究中开辟了一条途径。
In phase transition dynamics involving symmetry breaking, topological defects can be spontaneously created but it is suppressed in a spatially inhomogeneous system due to the spreading of the ordered phase information. We demonstrate the defect suppression effect in a trapped atomic Bose gas which is quenched into a superfluid phase. The spatial distribution of created defects is measured for various quench times and it is shown that for slower quenches, the spontaneous defect production is relatively more suppressed in the sample's outer region with higher atomic density gradient. The power-law scaling of the local defect density with the quench time is enhanced in the outer region, which is consistent with the Kibble-Zurek mechanism including the causality effect due to the spatial inhomogeneity of the system. This work opens an avenue in the study of nonequilibrium phase transition dynamics using the defect position information.
