Thermoelectric effect on diffusion in the two-dimensional Hubbard model

TL;DR

This paper investigates how thermoelectric effects influence charge and heat diffusion in the two-dimensional Hubbard model at strong coupling, revealing complexities in diffusive behavior relevant to cold-atom experiments.

Contribution

It introduces a detailed analysis of thermoelectric effects on diffusion in the Hubbard model, highlighting their impact on diffusive and hydrodynamic regimes.

Findings

Thermoelectric terms complicate the interpretation of diffusion.

Diffusion cannot be described by a single time scale due to thermoelectric effects.

Results are relevant for cold-atom experiments and heat conductivity measurements.

Abstract

We study charge and heat transport in the square lattice Hubbard model at strong coupling using the finite-temperature Lanczos method. We construct the diffusion matrix and estimate the effect of thermoelectric terms on diffusive and hydrodynamic time evolution. The thermoelectric terms prevent the interpretation of the diffusion in terms of a single time scale. We discuss our results in relation to cold-atom experiments and measurements of heat conductivity based on the measurements of heat diffusion.