Journal of Physical Studies 13(1), Article 4702 [8 pages] (2009) DOI: https://doi.org/10.30970/jps.13.4702 MAGNETIC PROPERTIES OF A STRONGLY CORRELATED SYSTEM ON THE BETHE LATTICE F. P. Mancini{1,2} 1Dipartimento di Fisica ıt ‟E. R. Caianiello”} and CNR-SPIN di Salerno Università degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (SA), Italy 2I.N.F.N. Sezione di Perugia, Via A. Pascoli, I-06123 Perugia, Italy

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 whose long-range charge ordered phase is observed, as well as the behavior of physical quantities that are 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 magnetic field.

PACS number(s): 71.10.Fd, 75.30.Kz, 71.10.-w

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