Fidelity Study of Superconductivity in Extended Hubbard Models
Abstract
The Hubbard model with local on-site repulsion is generally thought to possess a superconducting ground-state for appropriate parameters, but the effects of more realistic long-range Coulomb interactions have not been studied extensively. We study the influence of these interactions on superconductivity by including nearest and next-nearest neighbor extended Hubbard interactions in addition to the usual on-site terms. Utilizing numerical exact diagonalization, we analyze the signatures of superconductivity in the ground states through the fidelity metric of quantum information theory. We find that nearest and next-nearest neighbor interactions have thresholds above which they destabilize superconductivity regardless of whether they are attractive or repulsive, seemingly due to competing charge fluctuations.
Keywords
Cite
@article{arxiv.1505.01127,
title = {Fidelity Study of Superconductivity in Extended Hubbard Models},
author = {N. Plonka and C. J. Jia and Y. Wang and B. Moritz and T. P. Devereaux},
journal= {arXiv preprint arXiv:1505.01127},
year = {2015}
}
Comments
5 pages, 3 figures