Hidden Kondo lattice physics in single-orbital Hubbard models
Abstract
Single-orbital Hubbard models exhibit remarkably nontrivial correlation phenomena, even on nonfrustrated bipartite lattices. Some of these, like non-Fermi-liquid metal states, or the coexistence of heavy and light quasi-particles, are reminiscent of the properties of more complex multi-orbital or Kondo-lattice systems. Here, we use basis transformations to map single-orbital models to effective multi-orbital descriptions and clarify how a ferromagnetic Kondo-lattice-like behavior emerges in prototypical models with flat bands or van Hove singularities in the density of states: the Hubbard model on the diamond chain, square-lattice, Lieb lattice and honeycomb lattice. In particular, this mapping explains the non-Fermi-liquid states and pseudo-gaps found in the correlated metal regime.
Cite
@article{arxiv.2410.14583,
title = {Hidden Kondo lattice physics in single-orbital Hubbard models},
author = {Philipp Werner and Sayed Ali Akbar Ghorashi},
journal= {arXiv preprint arXiv:2410.14583},
year = {2025}
}