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• YFeO 3 have been studied with GGA and GGA+U reveal a semi-conductor and an Antiferromagnetic type-G behavior. • Magnetic anisotropy results for both approximations show that easy axis magnetization for YFeO 3 is along the c-axis. • Evaluation of the electric polarization and the magnetic transition temperature of the orthorhombic YFeO 3 has done. In this study, we have thoroughly investigated the electronic, magnetic, and electrical properties of yttrium orthoferrite using density functional theory (DFT) within the generalized gradient approximation (GGA) and the (GGA + U) approach, which incorporates the Hubbard term (U). Both approximations consistently reveal a semiconductor behavior and an antiferromagnetic behavior of type-G between the iron (Fe) ions. To delve deeper into the magnetic interactions within YFeO 3 , we have proposed a physical model. This model allows us to calculate the magnetic exchange coupling and magnetic anisotropy parameters through DFT calculations. Additionally, we have conducted computations to determine the electric polarization. Our results have shown that the electric polarization in YFeO 3 is exclusively derived from electronic polarization. We have also explored the relationship between the direction of electric polarization and the easy-axis magnetization. In our investigation, we found that both the electric polarization and easy-axis magnetization align along the c-axis in both approximations. Furthermore, we have examined the influence of the Hubbard term on the direction of polarization. To assess the magnetic temperature transition, we employed Monte Carlo simulations using the Ising model. The critical temperature, denoted as T N , obtained with the GGA approximation is found to be 726.66 K. Remarkably, this value closely matches the experimental critical temperature when compared to the critical temperature obtained with the GGA + U approximation. [ABSTRACT FROM AUTHOR]

Using the mean field approximation (MFA), we have successfully investigated the magnetic properties of the mixed spin S j = ± 3 , ± 2 , ± 1 , 0 and σ i = ± 3 2 , ± 1 2 Ising ferrimagnetic system in a graphene layer. The effects of different physical parameters, namely exchange interactions, anisotropies, external field and temperature on the critical, first-order, compensation and hysteresis behaviors have been examined. The results show that, for specific values of these parameters, interesting phenomena appeared, such as compensation and multi-loop hysteresis behavior. It was shown that the compensation phenomenon only occurs if the exchange interaction J A (interaction between spins σ i), is greater than a certain minimum value J A m i n. We have also shown that, for fixed values of the anisotropies, the relation between J A m i n and the exchange interaction J B (interaction between S j), is a linear one. In addition, we found that each of the behaviors mentioned above is sensitive to the change of a certain physical parameter. Finally, we have verified that our results are comparable with those of other works. • The effects of physical parameters on magnetic properties were examined. • The system presents a first- and second-order transition. • Compensation appears in the system for specific values of physical parameters. • The phenomenon of multi-loop hysteresis cycles is present in the system. [ABSTRACT FROM AUTHOR]

• A multi-walled mixed spin (1/2; 1; 1/2; 1) Ising nanowire with a basic hexagonal shape is built. • For ferrimagnetic and ferromagnetic sates, different magnetic properties are established. • The magnetization types and compensating behaviors are strongly influenced by different Hamiltonian settings. • Unique outcomes are discovered. Using the Effective Field Theory with correlation, we investigate the magnetic properties and the phase diagram of a mixed-spin (½, 1, ½, 1) Ising core-multi shell nanowire structure. Typical temperature dependence of the total magnetization, the core and shell magnetization for several fixed values of exchange couplings were discussed in detail. The phase diagrams of the critical and compensation temperatures were displayed in various Hamiltonian parameter planes. Our established results have been successfully compared with results from several experimental and theoretical studies. The ultimate objective is to stimulate research into the design and development of innovative nanomaterials for targeted applications. [ABSTRACT FROM AUTHOR]

• The critical temperature of FeNi and FePt alloys using Heisenberg interaction is closer to the experimental value than the Ising interaction. • The FeNi and FePt alloys prefer a ferromagnetic phase over the ferrimagnatic phase. • The Ising interaction predicts higher critical temperature for the FeNi alloy than the Heisenberg interaction. • The Heisenberg interaction predicts higher critical temperature for the FePt alloy than the Ising interaction. A Monte Carlo simulation has been used to explore the magnetic properties of L1 0 ordered FeNi and FePt binary alloys. Our Hamiltonians include Heisenberg interaction or Ising interaction. Our calculations of variations of specific heat C v , magnetic susceptibility χ and the magnetization M with the temperature T showed that predicted critical temperature for ferromagnetic phase is very close to the experimental values for these alloys. Also, thermal hysteresis loops, magnetic remanence, and the coercive field have been calculated. Moreover, the magnetic properties of the ferrimagnetic phase are presented. [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]