Effective-field theory for the magnetic and thermal properties of site- and bond-impure systems
نویسنده
چکیده
We present different effective-field and cluster-variation treatments of the magnetic spin-: Ising model for a fraction x of frozen-in or quenched non-magnetic impurities. The resulting picture for the critical curve. magnetisation, energy, specific heat and susceptibility is simple and compares very well with Monte Carlo and experimental data. Our results can thus be useful in the analysis of 'anomalies' in non-stoichiometric compounds such as metal oxides, mixed alloys and other substances up to the percolation threshold x,.
منابع مشابه
Magnetic Properties in a Spin-1 Random Transverse Ising Model on Square Lattice
In this paper we investigate the effect of a random transverse field, distributed according to a trimodal distribution, on the phase diagram and magnetic properties of a two-dimensional lattice (square with z=4), ferromagnetic Ising system consisting of magnetic atoms with spin-1. This study is done using the effectivefield theory (EFT) with correlations method. The equations are derived using...
متن کاملEffects of Magnetic Field in Creep Behavior of Three-Phase Laminated Composite Cylindrical Shells
Due to the importance effect of magnetic field on the history of long-term radial and circumfer-ential creep strain and radial displacement for a three-phase nano-composite exposed to an internal pressure and placed uniform temperature, the present article subject has been pro-posed. Three-phase nano-composite made of single-walled carbon nano tubes (SWCNTs)/ glass fiber (GF)/vinylester used to...
متن کاملMagnetic Properties and Phase Transitions in a Spin-1 Random Transverse Ising Model on Simple Cubic Lattice
Within the effective-field theory with correlations (EFT), a transverse random field spin-1 Ising model on the simple cubic (z=6) lattice is studied. The phase diagrams, the behavior of critical points, transverse magnetization, internal energy, magnetic specific heat are obtained numerically and discussed for different values of p the concentration of the random transverse field.
متن کاملAnalysis of Nonlinear Vibrations of Slightly Curved Tripled-Walled Carbon Nanotubes Resting on Elastic Foundations in a Magneto-Thermal Environment
In this work, nonlocal elasticity theory is applied to analyze nonlinear free vibrations of slightly curved multi-walled carbon nanotubes resting on nonlinear Winkler and Pasternak foundations in a thermal and magnetic environment. With the aid of Galerkin decomposition method, the systems of nonlinear partial differential equations are transformed into systems of nonlinear ordinary differentia...
متن کاملMagneto-Thermo-Elastic Stresses and Perturbation of Magnetic Field Vector in a Thin Functionally Graded Rotating Disk
In this paper, a semi-analytical solution for magneto-thermo-elastic problem in an axisymmetric functionally graded (FG) hollow rotating disk with constant thickness placed in uniform magnetic and thermal fields with heat convection from disk’s surfaces is presented. Solution for stresses and perturbation of magnetic field vector in a thin FG rotating disk is determined using infinitesimal theo...
متن کامل