Magnetic properties of a strongly correlated system on the Bethe lattice

TL;DR

This paper investigates how an external magnetic field influences the phase diagram and magnetic properties of a strongly correlated electron system modeled by the extended Hubbard model on a Bethe lattice, revealing significant effects on phase transitions and thermodynamic behavior.

Contribution

It provides new insights into the magnetic field's impact on charge order and thermodynamics in a Bethe lattice-based extended Hubbard model, a less explored area.

Findings

Magnetic field significantly alters the critical temperature for charge ordering.

Magnetization plateaus are induced by the magnetic field.

Thermodynamic quantities like specific heat and susceptibility are affected by magnetic field variations.

Abstract

We study the influence of an external magnetic field h on the phase diagram of a system of Fermi particles living on the sites of a Bethe lattice with coordination number z and interacting through on-site U and nearest-neighbor V interactions. This is a physical realization of the extended Hubbard model in the narrow-band limit. Our results establish that the magnetic field may dramatically affect the critical temperature below which a long-range charge ordered phase is observed, as well as the behavior of physical quantities, inducing, for instance, magnetization plateaus in the magnetization curves. Relevant thermodynamic quantities - such as the specific heat and the susceptibility - are also investigated at finite temperature by varying the on-site potential, the particle density and the magnetic field.