Li Jian, An Jin, Ting C S
Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204, USA.
Sci Rep. 2013 Nov 6;3:3147. doi: 10.1038/srep03147.
The impurities, introduced intentionally or accidentally into certain materials, can significantly modify their characteristics or reveal their intrinsic physical properties, and thus play an important role in solid-state physics. Different from those static impurities in a solid, the impurities realized in cold atomic systems are naturally mobile. Here we propose an effective theory for treating some unique behaviors exhibited by ultracold mobile impurities. Our theory reveals the interaction-induced transition between the extended and localized impurity states, and also explains the essential features obtained from several previous models in a unified way. Based on our theory, we predict many intriguing phenomena in ultracold systems associated with the extended and localized impurities, including the formation of the impurity-molecules and impurity-lattices. We hope this investigation can open up a new avenue for the future studies on ultracold mobile impurities.
有意或无意引入某些材料中的杂质，能够显著改变其特性或揭示其内在物理性质，从而在固态物理中发挥重要作用。与固体中的那些静态杂质不同，冷原子系统中实现的杂质具有天然的可移动性。在此，我们提出一种有效理论来处理超冷移动杂质所表现出的一些独特行为。我们的理论揭示了扩展态和局域态杂质之间由相互作用引起的转变，并且还以统一的方式解释了从先前几个模型中获得的基本特征。基于我们的理论，我们预测了超冷系统中与扩展态和局域态杂质相关的许多有趣现象，包括杂质分子和杂质晶格的形成。我们希望这项研究能够为未来关于超冷移动杂质的研究开辟一条新途径。
