The mean-field approximation based on the Gibbs-Bogoliubov inequality and Monte Carlo simulations based on the Metropolis method in the Blume–Emery–Griffiths model were used to successfully examine a ...hexagonal Ising nanowire with spin-1. It was found that the model displays fascinating phase diagrams in various planes of interest by using both methods. The investigation of magnetic hysteresis cycles also exhibits interesting properties. The model not only presents first- and second-order phase transition lines, but also the tricritical and isolated critical points, multi-compensation temperatures, and magnetic hysteresis behavior with one to eight cycles.
•The mean-field approximation based on the Gibbs-Bogoliubov inequality is applied.•The Monte Carlo simulations based on the Metropolis method is employed.•Spin-1 Blume–Emery–Griffiths model for hexagonal Ising nanowire is investigated.•First- and second-order transitions, tricritical and isolated critical points are found.•Multi-compensation and magnetic hysteresis with one to eight cycles are observed.
The magnetic properties and hysteresis loops for the hexagonal Ising nanowire (HIN) with core–shell structure consisting of spin-32 are considered in the Blume–Emery–Griffiths (BEG) model by using ...the mean-field approximation (MFA) based on the Gibbs–Bogoliubov inequality for the free energy. The effects of various bilinear and biquadratic interaction parameters between the core, between the shell, and between the core and shell spins are considered for the phase diagrams of the model when temperature T=0 and T≠0 in addition to the crystal and external magnetic fields effects. The numerical calculations reveal that the model yields first- and second-order phase transition lines and tricritical points. In addition to the isolated critical and critical end-points, the model exhibits at most two compensation temperatures and interesting multiple hysteresis magnetic loops behaviors strongly dependent on the model parameters.
•The core–shell structure with spin-3/2 was considered in the Blume–Emery–Griffiths model.•Mean-field approximation based on the Gibbs–Bogoliubov inequality for free energy was employed.•The magnetic properties and hysteresis loops for the hexagonal Ising nanowire were examined.•The ground state and temperature-dependent phase diagrams were calculated.•Tricritical, isolated critical, critical end-points and at most two compensation points were observed.
