Robust Strange Metallicity across Attractive and Repulsive Hubbard Models
Abstract
Using determinant quantum Monte Carlo simulations, we compare charge transport in the two-dimensional attractive and repulsive Hubbard models at strong coupling, |U|/t=6. Although the interaction with opposite signs generates qualitatively different low-energy spin, charge, and pairing correlations, both exhibit approximately linear-in-temperature resistivity over a broad intermediate- and high-temperature regime. At asymptotically high temperature this common behavior follows from the moment expansion of the conductivity, whose leading contribution is even in U. More strikingly, the similarity persists to temperatures well below |U|, where strong interaction-dependent correlations have already developed, and also irrespective of whether resistivity crosses the MIR limit. Using the Nernst--Einstein relation, we find that the common linear-in-temperature resistivity is primarily associated with an approximately Curie-like charge compressibility and weakly temperature-dependent diffusivity. The two models separate only at lower temperatures, where the attractive model develops a pronounced feature in the charge diffusivity correlated with signatures of pair formation. These results show that linear-in-temperature incoherent transport in the Hubbard model can be remarkably insensitive to the microscopic nature of the low-energy correlations. Our results suggest that transport in the incoherent regime appears insensitive to what the system will ultimately become at low temperature; the distinction between competing low-energy states becomes visible only when their characteristic correlations acquire sufficiently long spatial or temporal coherence.
Related
- Homogeneous attractive Bose-Einstein condensates with repulsive three-body interactions: the two-dimensional case
- Homogeneous attractive Bose-Einstein condensates with repulsive three-body interactions: the one-dimensional case
- Superconductivity in the Repulsive Hubbard Model on Different Geometries Induced by Density-Assisted Hopping
- Pairing order and condensate fraction across the BCS-BEC crossover in the two-dimensional attractive Hubbard model
- Weyl superconductivity from Feshbach resonance in the three-dimensional repulsive Hubbard model
BibTeX
@misc{ma2026robust,
title = {{Robust Strange Metallicity across Attractive and Repulsive Hubbard Models}},
author = {Xiaoyue Ma and Emily Z. Zhang and Thomas P. Devereaux},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.26971},
eprint = {2609.26971},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.26971},
}
RIS
TY - UNPB
TI - Robust Strange Metallicity across Attractive and Repulsive Hubbard Models
AU - Xiaoyue Ma
AU - Emily Z. Zhang
AU - Thomas P. Devereaux
PY - 2026
DA - 2026/09/22
PB - arXiv
DO - 10.48550/arxiv.2609.26971
UR - https://arxiv.org/abs/2609.26971
AB - Using determinant quantum Monte Carlo simulations, we compare charge transport in the two-dimensional attractive and repulsive Hubbard models at strong coupling, |U|/t=6. Although the interaction with opposite signs generates qualitatively different low-energy spin, charge, and pairing correlations, both exhibit approximately linear-in-temperature resistivity over a broad intermediate- and high-temperature regime. At asymptotically high temperature this common behavior follows from the moment expansion of the conductivity, whose leading contribution is even in U. More strikingly, the similarity persists to temperatures well below |U|, where strong interaction-dependent correlations have already developed, and also irrespective of whether resistivity crosses the MIR limit. Using the Nernst--Einstein relation, we find that the common linear-in-temperature resistivity is primarily associated with an approximately Curie-like charge compressibility and weakly temperature-dependent diffusivity. The two models separate only at lower temperatures, where the attractive model develops a pronounced feature in the charge diffusivity correlated with signatures of pair formation. These results show that linear-in-temperature incoherent transport in the Hubbard model can be remarkably insensitive to the microscopic nature of the low-energy correlations. Our results suggest that transport in the incoherent regime appears insensitive to what the system will ultimately become at low temperature; the distinction between competing low-energy states becomes visible only when their characteristic correlations acquire sufficiently long spatial or temporal coherence.
ER -