Polkovnikov Anatoli, Altman Ehud, Demler Eugene
Department of Physics, Harvard University, Cambridge, MA 02138, USA.
Proc Natl Acad Sci U S A. 2006 Apr 18;103(16):6125-9. doi: 10.1073/pnas.0510276103. Epub 2006 Apr 6.
We consider a problem of interference between two independent condensates that lack true long-range order. We show that their interference pattern contains information about correlation functions within each condensate. As an example, we analyze the interference between a pair of one-dimensional interacting Bose liquids. We find universal scaling of the average fringe contrast with system size and temperature that depends only on the Luttinger parameter. Moreover, the full distribution of the fringe contrast, which is also equivalent to the full counting statistics of the interfering atoms, changes with interaction strength and lends information on high-order correlation functions. We also demonstrate that the interference between two-dimensional condensates at finite temperature can be used as a direct probe of the Kosterlitz-Thouless transition. Finally, we discuss the generalization of our results to describe the interference of a periodic array of independent fluctuating condensates.
我们考虑两个缺乏真正长程序的独立凝聚体之间的干涉问题。我们表明，它们的干涉图样包含了每个凝聚体内关联函数的信息。作为一个例子，我们分析了一对一维相互作用玻色液体之间的干涉。我们发现平均条纹对比度随系统尺寸和温度的普遍标度关系，该关系仅取决于卢廷格参数。此外，条纹对比度的完整分布，这也等同于干涉原子的全计数统计，随相互作用强度而变化，并给出了高阶关联函数的信息。我们还证明，有限温度下二维凝聚体之间的干涉可作为对科斯特利茨 - 索利斯转变的直接探测。最后，我们讨论了将我们的结果推广以描述独立波动凝聚体的周期性阵列的干涉。
