Magnetic properties of a strongly correlated system on the Bethe lattice

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.