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In this work, the Effective Field Theory (EFT) based on the probability distribution method is used to study the phase diagrams of an antiferroelectric nanowire with core/shell morphology, in the presence of a random transverse field. We have investigated the effects of the temperature, the concentration c , the surface and the interfacial couplings on the critical and the compensation behaviors (T c and T comp) of the system. The polarization, the susceptibility and the pyroelectric coefficient as a function of the temperature are examined. In addition, the phase diagrams of the nanowire are investigated in detail by modifying the system parameters. It is found that the interfacial coupling | J int / J c | shifts the random transverse field to higher values, therefore the area of the ordered phase is enlarged, which could affects the critical and the compensation temperatures. • The phase diagrams of a nanowire with antiferroelectric interfacial coupling are examined by the effective field theory. • The effect of the antiferromagnetic interfacial coupling on the critical and the compensation behaviors is studied. • The influence of the random transverse field on electric properties. • The dependence of the polarization, pyroelectric coefficient and susceptibility on the temperature are investigated. [ABSTRACT FROM AUTHOR]

Monte Carlo simulation has been performed to explore the compensation temperature and the critical behavior on a triple layer spin (1-1/2-1) cubic system with ferrimagnetic coupling at the two interfaces. Our results showed that the compensation temperature T c o m p is less influenced by increasing the number of layers or the exchange coupling of the spin 1 2 layer. Gradual increases in the critical temperature T c is shown with increasing the exchange coupling in spin 1 layers or spin 1 2 layer. Finally, the above results have been confirmed by the simulation performed on the heat capacity and Binder cumulant. • The compensation temperature is less influenced by increasing the number of layers. • Compensation temperature disappears for specific values of exchange interaction. • Gradual increases in the critical temperature with increasing the exchange coupling. • Compensation temperature disappears for specific values of exchange interaction. [ABSTRACT FROM AUTHOR]

We study the magnetic and thermodynamic properties of a spin- 1 ∕ 2 Ising system containing three layers, each of which is composed exclusively of one out of two possible types of atoms, A or B. The A-A and B-B bonds are ferromagnetic while the A-B bonds are antiferromagnetic. The study is performed through Monte Carlo simulations using the Wolff algorithm and the data are analyzed with the aid of the multiple-histogram reweighting technique and finite-size scaling tools. We verify the occurrence of a compensation phenomenon and obtain the compensation and critical temperatures of the model as functions of the Hamiltonian parameters. The influence of each parameter on the overall behavior of the system is discussed in detail and we present our results in the form of phase diagrams dividing the parameter space in regions where the compensation phenomenon is present or absent. Our results may provide invaluable information for experimentalists seeking to build materials with desired characteristics. • Ferrimagnetic spin-1/2 Ising trilayer is studied. • Each layer can only have atoms of one out of two types (A or B). • Only A-B couplings are antiferromagnetic. • Magnetic properties of the system are studied through Monte Carlo simulations. • Compensation phenomenon is found and phase diagrams are obtained. [ABSTRACT FROM AUTHOR]

• We study the magnetic and hysteretic properties of Graphene-Based Janus Materials using Monte Carlo calculations and mean field theory. • We show the effects of the number and the positions of dopants on thermodynamic quantities. • We give the conditions for the occurrence of compensation temperature. • We describe the influence of the system's parameters on the hysteresis curves. Based on our works [1–4] , we report the magnetic and hysteretic properties of graphene-based Janus materials namely, pure and doped zigzag graphone nanoribbons, hexagonal core/shell graphene-like nanoribbon, and graphyne core/shell nanoparticle, within the framework of both Monte Carlo calculations and mean field theory. We have reported the effects of the Hamiltonian parameters on the magnetic and the thermodynamic quantities of the systems. The total magnetization, the susceptibility, the specific heat, and the hysteresis curves, as well as the critical temperature and the compensation behavior, that is of crucial importance for technological applications such as thermo-optical recording, are studied. A number of characteristic behaviors are found, such as the existence of two new and non-classified magnetization profiles in addition to the Q -, P -, and N -types of compensation behavior and the occurrence of square, single, and triple hysteresis loops which exhibit different step effects and various shapes. [ABSTRACT FROM AUTHOR]

The critical, first order, and spin compensation behaviors of a ferrimagnetic Ising system, consisting of spins S = 3 ∕ 2 and Q = 5 ∕ 2 alternating on a square lattice, have been studied by Monte Carlo (MC) simulations and Mean-Field Theory (MF). The system is defined by a Hamiltonian (H) that contains ferromagnetic next-nearest-neighbors interactions between S spins (J 2 ′) and Q spins (J 3 ′), as well as external magnetic field (h ′) and anisotropy (D 1 ′ , D 2 ′) interactions. The effects of D 1 ′ crystal and h ′ magnetic fields on the critical, double first order transition, and compensation phenomena are analyzed in detail. We found that the existence of a double first order phase transition depends on the temperature and the strength of h ′. • We calculate the finite temperatura diagrams of the magnetization of the model. • The system exhibits compensation temperatures and first order transitions. • We analyze the relation between critical, compensation and first order temperatures. • The compensation temperatures and first order transitions depends of h' and D ' 1. [ABSTRACT FROM AUTHOR]