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The purpose of this article is to investigate the magnetic properties and the hysteresis loops behavior of a ferrimagnetic cubic nanowire with mixed spins S_A = 3/2 and S_B = 2.

We have used the Monte Carlo simulation to examine the influences of the exchange interaction J_B, the crystal field ∆ and the temperature on the magnetic properties and hysteresis loops of the nanowire. More exactly, we have shown the temperature dependence of the sublattice magnetizations (m_A and m_B) and the total magnetization (M) for several values of the Hamiltonian parameters, as well as the corresponding phase diagrams. Finally, the effect of an external magnetic field is studied by plotting the hysteresis loops of the system for different values of exchange interaction, crystal field and temperature.

The obtained results show the existence of second-order phase transitions, as well as the compensation behavior. Moreover, according to the values of the Hamiltonian parameters, the system can exhibit one, two or three hysteresis loops.

The magnetic nanowires are of great interest in experimental works, but without theoretical explanations, the experimental results cannot be clarified in depth. For this, we contribute through this theoretical study to understand the nanowires, especially those with mixed spins (2, 3/2).

The purpose of this paper is to study the magnetic properties and the hysteresis behavior of a ferrimagnetic cubic Ising nanowire with mixed spins S = 3/2 and S = 5/2 in which the atoms are placed alternately.

In order to investigate the effects of the exchange interactions and crystal field on the magnetic properties and hysteresis behavior of the nanowire, we have used the Monte Carlo simulation. More precisely, we have plotted the thermal variations of the sublattice and total magnetizations for different values of the Hamiltonian parameters, and we have presented the corresponding phase diagrams. In addition, the influence of an external magnetic field is examined by plotting the variations of hysteresis loops with the change of temperature and crystal field.

All phase transition found in this study are of second-order and the critical temperatures increase linearly with the increase of the exchange interactions. The compensation temperatures appear only for some domains of crystal field D and exchange interaction J_B of the sublattice (B). Moreover, when studying the hysteresis behavior, the system can show one or double hysteresis loops.

The authors consider that this research is consistent with the scientific axis of the journal which benefits a great esteem in our country and in the world. In addition, the results are of technological interest.

The authors investigate the magnetic properties of a mixed spin-3/2 and spin-2 Blume-Capel model on square and cubic lattices with two different single-ion anisotropies.

To study the critical behavior of a mixed spin-3/2 and spin-2 system, the authors have used a real space renormalization group approximation and specifically the Migdal-Kadanoff technique. The authors give the phase diagrams for two different cases: (1) on the (Δ/|J|, 1/|J|) plane with Δ_A = Δ_B = Δ, and (2) on the (Δ_A/|J|, 1/|J|) and (Δ_B/|J|, 1/|J|) planes for selected values of Δ_B/|J| and Δ_A/|J|, respectively.

The phase diagrams obtained show that the system exhibits both second- and first-order phase transitions as well as tricritical points for some values of the anisotropies. Moreover, using the variation of the free energy and its derivative at low temperatures, the authors have seen the appearance of first-order transitions at very low temperatures.

Few investigations of mixed spin-3/2 and spin-2 systems with crystal field have been realized. For this reason, the authors use the renormalization group approach to complete the work done on these systems. In absence of an exact solution, this contributes to the synthesis of the approximation results on mixed spins models.