Magnetism, transport, and thermodynamics in two-dimensional half-filled Hubbard superlattices

TL;DR

This study investigates the magnetic, transport, and thermodynamic properties of a 2D Hubbard model with layered interactions using quantum Monte Carlo simulations, revealing effects of interactions on magnetic correlations, transport, and potential cooling applications.

Contribution

It introduces a detailed analysis of layered distributed interactions in the 2D Hubbard model, highlighting their impact on magnetic, transport, and thermodynamic behaviors, including cooling protocols.

Findings

Antiferromagnetic correlations confirmed at T=0.

Transport is enhanced in non-repulsive layers at large interactions.

Adiabatic switching of interactions can reduce system temperature.

Abstract

We study magnetic, transport and thermodynamic properties of the half-filled two-dimensional ($2D$) Hubbard model with layered distributed repulsive interactions using unbiased finite temperature quantum Monte Carlo simulations. Antiferromagnetic long-ranged correlations at $T=0$ are confirmed by means of the magnetic structure factor and the onset of short-ranged ones is at a minimum temperature which can be obtained by peaks in susceptibility and specific heat following an RPA prediction. We also show that transport is affected in the large interaction limit and is enhanced in the non-repulsive layers suggesting a change of dimensionality induced by increased interactions. Lastly, we show that by adiabatically switching the interactions in layered distributed patterns reduces the overall temperature of the system with a potential application in cooling protocols in cold atoms systems.