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The magnetic properties of spins -S and σ Ising model on the Bethe lattice have been investigated by using the Monte Carlo simulation. The thermal total magnetization and magnetization of spins S and σ with the different exchange interactions, different external magnetic field and different temperatures have been studied. The critical temperature and compensation temperature have been deduced. The magnetic hysteresis cycle of Ising ferrimagnetic system on the Bethe lattice has been deduced for different values of exchange interactions between the spins S and σ , for different values of crystal field and for different sizes. The magnetic coercive filed has been deduced. [ABSTRACT FROM AUTHOR]

Nonequilibrium phase transition properties of a mixed Ising ferrimagnetic model consisting of spin-1/2 and spin-3/2 on a square lattice under the existence of a time dependent oscillating magnetic field have been investigated by making use of Monte Carlo simulations with a single-spin flip Metropolis algorithm. A complete picture of dynamic phase boundary and magnetization profiles have been illustrated and the conditions of a dynamic compensation behavior have been discussed in detail. According to our simulation results, the considered system does not point out a dynamic compensation behavior, when it only includes the nearest-neighbor interaction, single-ion anisotropy and an oscillating magnetic field source. As the next-nearest-neighbor interaction between the spins-1/2 takes into account and exceeds a characteristic value which sensitively depends upon values of single-ion anisotropy and only of amplitude of external magnetic field, a dynamic compensation behavior occurs in the system. Finally, it is reported that it has not been found any evidence of dynamically first-order phase transition between dynamically ordered and disordered phases, which conflicts with the recently published molecular field investigation, for a wide range of selected system 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]

• 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]