Thermodynamics of the metal-insulator transition in the extended Hubbard model from determinantal quantum Monte Carlo

TL;DR

This study uses determinantal quantum Monte Carlo simulations to explore the thermodynamic behavior and phase transition nature of the extended Hubbard model with non-local interactions at finite temperature.

Contribution

It provides new insights into the thermodynamics and the nature of the metal-insulator transition in the extended Hubbard model with non-local interactions, using sign-problem free quantum Monte Carlo methods.

Findings

Assessment of a first-order metal-insulator transition scenario.

Analysis of thermodynamic properties with non-local interactions.

Validation of variational calculations in the extended Hubbard model.

Abstract

Using finite-temperature determinantal quantum Monte Carlo simulations, we examine the thermodynamic properties of the extended Hubbard model on the half-filled square lattice in the Slater regime at intermediate coupling. We consider both the case of nearest-neighbor interactions and long-range Coulomb interactions, for coupling strengths in which the presence of non-local interactions still allows us to perform sign-problem free quantum Monte Carlo simulations. In particular, we assess a recently proposed scenario from variational calculations in terms of a first-order metal-insulator transition in this interaction regime.