Pair correlations in the attractive Hubbard model
Quantum Gases
2020-05-20 v1
Abstract
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.
Cite
@article{arxiv.2005.09121,
title = {Pair correlations in the attractive Hubbard model},
author = {C. F. Chan and M. Gall and N. Wurz and M. Köhl},
journal= {arXiv preprint arXiv:2005.09121},
year = {2020}
}