Thermal and magnetic phase transition properties of a binary alloy spherical nanoparticle: A Monte Carlo simulation study

Abstract

We have used the Monte Carlo (MC) simulation method with Metropolis algorithm to study the finite temperature phase transition properties of a binary alloy spherical nanoparticle with radius r of the type A p B 1−p . The system consists of two different species of magnetic components, namely, A and B, and the components of the system have been selected A and B to be as σ = 1/2 and S = 1, respectively. A complete picture of phase diagrams, total magnetizations and susceptibilities in related planes have been presented, and the main roles of the radius of nanoparticle, active concentration value of type-A atoms as well as other system parameters on the thermal and magnetic phase transition features of the considered system have been discussed in detail. Our MC investigations clearly show that it is possible to control the critical characteristic behaviors of the system with the help of adjustable Hamiltonian parameters.

Investigation of Magnetic Properties of Spin 5/2 Ising Chain by Using Transfer Matrix Method

“…Since the matrix is identical for ( ), ( ) and so on, the partition function is then given by = ∑ ( ) = ( ) = ∑ { } (6) while ≫ 1 the Helmholtz free energy is = − ( ) where is the biggest eigenvalues of TM in equation (5). We can construct thermodynamic expressions as internal energy E equation (7), ferromagnetic order parameter (magnetization) m equation (8), the magnetic susceptibility equation (9), entropy S equation (10) and the specific heat equation (11) by using Helmholtz free energy F.…”

“…Ising model [9], can be used to describe the material properties such as phase transition and temperature dependent magnetization. Recent works are mainly focused on exactly solvable spin 1/2 and spin 1 systems based on Monte Carlo and Ising models [10,11]. This kind of spin chain compounds shows a 1D ferromagnetic behavior modeled by spin chains [12].…”