The diluted mixed spin‐1/2 and spin‐3/2 Ising model in a longitudinal random field

Abstract

The diluted mixed spin Ising system consisting of spin‐1/2 and spin‐3/2 with a longitudinal random‐field is studied by the use of effective‐field theory with correlations (EFT). The equations are derived using a probability distribution method based on the use of Van der Waerden identities. The phase diagrams and thermal behaviors of magnetization are investigated numerically for the honeycomb lattice (z = 3) when the random field is trimodally distributed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Anisotropic Heisenberg model for the mixed spin-3/2 and spin-1/2 under random crystal field

“…The first technique is the effective field theory (EFT) which was considered in the calculation of magnetizations and phase diagrams [9], the critical properties in a transverse field [10], magnetic properties in a longitudinal magnetic field [11], the magnetic and hysteresis behaviors for a bilayer model [12], bimodal random-crystal field distribution effects [13], for a ferromagnetic or antiferromagnetic bilayer system with transverse field [14,15], in a random field [16], and for a trimodal random-field distribution [17]. Some of the works with a diluted model were also examined in the EFT in a random field [18], with coordination numbers 3 and 4 [19], in a longitudinal random field [20], for transverse Ising model [21,22] and for the study of the magnetic properties [23]. In addition to the EFT studies, the Monte Carlo algorithm [24], the exact recursion relations (ERR) were used on the Bethe lattice (BL) [25], by establishing a mapping correspondence with the eight-vertex model [26], an exact star-triangle mapping transformation [27], the ERR's on a two-fold Cayley tree [28], on the Union Jack lattice by means of a mapping correspondence with the eight-vertex model [29], on a rope ladder it was examined by combining two exact analytical methods, i.e., decoration-iteration mapping transformation and standard transfer-matrix method [30], within the mean-field approximation [31] and with the use of the ERR's on the BL [32], on a two-layer BL [33] and ±J model [34].…”

Monte Carlo Simulation of a Mixed Spin‐1/2 and Spin‐3/2 Ising Ferrimagnetic System with Site Dilution

“…[ 68 ] Another Monte Carlo study on a 3/2−5/2 model shows the interesting result that some combinations of magnetic impurities and site dilution can induce the appearance of compensation points. [ 69 ] There have been some studies of the diluted 1/2−3/2 Ising model based on effective field theories in hexagonal, [ 70 ] square, [ 70,71 ] cubic, [ 72 ] and 3D honeycomb [ 73 ] lattices. These mean field studies seem to indicate that compensation points can appear in diluted models even in the absence of next‐nearest neighbors interactions.…”

Phase Diagrams of Generalized Spin-S Magnetic Binary Alloys

“…There are comprehensive works about mixed-spin Ising models which consist of two different spin values in the literature. Mixed Ising models with half-integer half-integer spins have been examined within the framework of EFT [19][20][21][22], MC [23][24][25], exact recursion relations [26] and Oguchi approximation [27]. No matter which method or lattice model has been used, the system holds minimum half integer s = ±1/2 ordered states at values of large negative single ion anisotropy parameter [22-24, 26, 27].…”