Insulator-pseudogap crossover in the Lieb lattice
Strongly Correlated Electrons
2021-06-09 v1
Abstract
We study the attractive Hubbard model in the Lieb lattice to understand the normal state above the superconducting critical temperature in a flat band system. We use cluster dynamical mean-field theory to compute the two-particle susceptibilities with full quantum fluctuations included in the cluster. At interaction strengths lower than the hopping amplitude, we find that the normal state on the flat band is an insulator. The insulating behavior stems from the localization properties of the flat band. A flat-band enhanced pseudogap with a depleted spectral function arises at larger interactions.
Cite
@article{arxiv.2007.05118,
title = {Insulator-pseudogap crossover in the Lieb lattice},
author = {Kukka-Emilia Huhtinen and Päivi Törmä},
journal= {arXiv preprint arXiv:2007.05118},
year = {2021}
}
Comments
6 pages, 4 figures and a supplementary material