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We proposed a ferrimagnetic mixed-spin (1, 3/2) Ising model to study the magnetic behaviors of a graphene ladder-type chain structure by means of Monte Carlo simulation. Induced by different physical parameters, the system can display interesting magnetic behaviors such multiple saturation magnetization values, double-peak susceptibility curves, and multi-cycle hysteresis loops. The results illustrate that crystal-field, exchange coupling and external magnetic field show significant impacts on the magnetic properties of the system. • A mixed-spin (1, 3/2) Ising model was proposed to describe a ferrimagnetic graphene ladder-type chain structure. • Magnetization, magnetic susceptibility, and internal energy were studied by Monte Carlo method. • The phase diagrams of the blocking temperature in three-dimensional space was given. • Multi-cycle hysteresis behaviors were discovered caused by various parameters. [ABSTRACT FROM AUTHOR]

• The mixed spin Ising model is generally used as a modeling tool to study ferrimagnetism. • Monte Carlo simulation to study the critical and the compensation behaviors of a cubic lattice considering a mixed spin- 3/2 and spin-1 Ising ferrimagnetic model. • The presence of crystal and external magnetic fields is not sufficient to generate the compensation phenomenon in a mixed spins. In this study, we perform Monte Carlo simulations to study the magnetic properties of a mixed Ising model on a cubic lattice where spins S i A = 1 and σ J B = 3/2 are located in sublattice A and B, respectively. The proposed Hamiltonian includes coupling to nearest-neighbors interactions, next-nearest-neighbors interactions, crystal fields D S and D σ and external magnetic field h. We perform exact ground-state calculations for our model. The obtained results show the behavior of the critical temperature with the presence of the compensation temperatures under a certain range of parameters. Particularly, we found that the existence of compensation temperatures depends on the strength of the coupling to the next nearest neighbors between the S i A spins and between the σ J B spins, and it appears in a certain range of values of the external magnetic and crystal field of different spins. [ABSTRACT FROM AUTHOR]

We applied Monte Carlo simulation to investigate the thermodynamic properties and hysteresis loops of the hexagonal core-shell nanoparticle described by a ferrimagnetic mixed-spin (3/2, 5/2) Ising model. The results revealed the significance of the single-ion anisotropy, exchange coupling, external magnetic field in dominating various thermodynamic quantities and hysteresis loops. We obtained the variation of the critical temperature with various parameters. Under certain parameter conditions, the system may exhibit rich multiple-loop hysteresis behaviors, depending on the competition among the physical parameters. An Ising model of nanoparticle with hexagonal core-shell structure is proposed. The multiple profiles and saturation values of the magnetization are discovered in the system. [Display omitted] • A ferrimagnetic hexagonal core-shell nanoparticle was proposed under an external magnetic field. • Magnetization, susceptibility, and internal energy were discussed by Monte Carlo simulation. • The compensation temperature was found under the effect of single-ion anisotropy. • Multiple-loop hysteresis behaviors were discovered due to the competition among different physical parameters. [ABSTRACT FROM AUTHOR]

• The graphene-like quantum dots with mixed-spin (3/2, 5/2) have been investigated. • The magnetic and thermodynamic behaviors have been explored. • The turnover phenomenon has been found. • The triple-loop behavior has been observed. Based on the Monte Carlo simulation, we have investigated the magnetic and thermodynamic behaviors of the graphene-like quantum dots described by a ferrimagnetic mixed-spin (3/2, 5/2) Ising model. The curves of the magnetization, magnetic susceptibility, internal energy and the specific heat as a function of temperature have been given under various physical parameters. The interesting turnover phenomenon has been found owing to the competition between the crystal field and temperature. It is found that the value of the blocking temperature increases with decreasing the crystal field or increasing the exchange coupling and external magnetic field. We have also investigated the hysteresis loops and found the impossibility of the triple-loop hysteresis behavior for certain parameters. The area of the hysteresis loops can be improved by increasing the exchange coupling and decreasing the absolute values of the crystal field and temperature. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a ferrimagnetic mixed-spin (1, 3/2) Ising model to describe the ladder-like graphene nanoribbon. Using the Monte Carlo simulation, the effects of the anisotropies, exchange couplings, longitudinal magnetic field and temperature on the magnetic and thermodynamic properties were investigated. Typical temperature dependences of thermodynamics quantities such as magnetization, susceptibility and internal energy were presented under the influence of various physical parameters. The phase diagrams of blocking temperature were obtained in the different parameter planes. In particular, we also found some interesting double hysteresis loops behavior for certain physical parameters. Our results are consistent with those obtained by some theoretical and experimental researches. • The ferrimagnetic mixed-spin (1, 3/2) Ising ladder-like graphene nanoribbon in the longitudinal magnetic field has been studied. • Magnetization, susceptibility and internal energy have been discussed. • The phase diagrams of the blocking temperature under the influence of different parameters have been obtained. • The double hysteresis loops behavior has been found for certain physical parameters. [ABSTRACT FROM AUTHOR]