论文标题
有吸引力的哈伯德模型中的配对相关性
Pair correlations in the attractive Hubbard model
论文作者
论文摘要
费米子配对的机制是理解各种现象的关键，例如高温超导性和铜材料中的伪群阶段。我们使用二维光学晶格中的超低费米子研究了有吸引力的哈伯德模型中的对相关性。通过将波动散引血定理和状态的压缩性方程组合在一起，我们提取相互作用的对相关函数，并推断成对的特征长度比例作为相互作用和密度填充的函数。在足够低的填充且现场相互作用较弱时，我们观察到，即使在超流体过渡温度的温度下，这对相关性甚至在几个晶格位点延伸。
The mechanism of fermionic pairing is the key to understanding various phenomena such as high-temperature superconductivity and the pseudogap phase in cuprate materials. We study the pair correlations in the attractive Hubbard model using ultracold fermions in a two-dimensional optical lattice. By combining the fluctuation-dissipation theorem and the compressibility equation of state, we extract the interacting pair correlation functions and deduce a characteristic length scale of pairs as a function of interaction and density filling. At sufficiently low filling and weak on-site interaction, we observe that the pair correlations extend over a few lattice sites even at temperatures above the superfluid transition temperature.
