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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]

In this work, we study the magnetic properties of a borophene core-shell structure with spins σ = 5/2 and S = 3/2, using Monte Carlo simulations. We start by discussing the ground state phase diagrams corresponding to several physical parameters. Then the magnetizations and the susceptibilities have been analyzed. Besides, we explore the thermal magnetization behavior under the effect of the reduced exchange coupling interactions. Furthermore, we investigate the presence of the compensation temperature induced by the presence of a core shell structure and resulted from the variation of the reduced coefficient coupling. Finally, the variation of the total magnetizations as a function of the reduced exchange coupling interactions, the crystal and the external fields has been discussed. • Monte Carlo Simulations is used to investigate the magnetic properties of the core-shell Borophene. • The ground state phase diagrams are established. • The effect of exchange coupling interactions and magnetic external and crystal fields are analyzed. • The existence of compensation Temperature is studied. • The hysteresis cycles are explored. [ABSTRACT FROM AUTHOR]

In this study, a bilayer Kagome lattice with RKKY interaction is described using a ferrimagnetic mixed spin-3/2 and spin-2 Ising model. Interesting compensation temperature and hysteresis loops of the system generated by various physical parameters, such as the crystal fields of sublattices (D a , D b), the interlayer exchange coupling (J R) and the intralayer exchange coupling (J b) are explored using Monte Carlo simulation. The results demonstrate that the compensation temperature (T comp), weaker D a and J b , and stronger D b , are favourable for the emergence of the compensation temperatures. Besides, under certain physical parameters, the system may exhibit triple-loop hysteresis behavior and multiple magnetization plateaus. • A ferrimagnetic mixed-spin (3/2, 2) Ising model on the bilayer Kagome lattice with RKKY interaction was proposed. • The effects of the crystal field, exchange coupling and non-magnetic layer were studied. • Magnetization, partial magnetization, and susceptibility were discussed. • Phase diagrams of the critical and compensation temperatures were obtained. • Interesting multi-loop hysteresis characteristics and magnetization plateaus were found. [ABSTRACT FROM AUTHOR]

Magnetic properties of a superlattice that consists of three square layers with Ising spins σ = 1 / 2 , s = 1 and q = 5 / 2 , are investigated by means of standard Monte Carlo simulations and Mean Field Theory. The Hamiltonian model comprises contributions of intralayer and interlayer exchange interactions and the applied external magnetic field. Effects of the external magnetic field on magnetic behaviors have been thoroughly studied in the presence of thermal excitation. Ground state and thermal phase diagrams are numerically computated by both methods. Ground state phase diagrams of the system exhibit one ferromagnetic phase (1/2, 1, 5/2) and three ferrimagnetic ones: (−1/2, 1, 5/2), (−1/2, −1, 5/2) and (−1/2, 1, −5/2). A number of interesting phase diagrams and phenomena have been found, including hysteresis behaviors. [ABSTRACT FROM AUTHOR]

Abstract The ferrimagnetic-ferromagnetic-ferrimagnetic quaternary alloy is constructed on the Bethe lattice in the compound form as AB p C q D r and formulated in terms of the exact recursion relations in the standard-random approach. The QA is designed on the BL by placing the A atoms (spin-1) only on the sites of odd shells and randomly placing B (spin-3/2), C (spin-5/2) or D (spin-2) atoms with probabilities, or concentrations, p , q and r , respectively, on the sites of even shells. The phase diagrams are obtained from the thermal analysis of the order-parameters. It is also found that the model yields only one compensation temperature. Highlights • The ferrimagnetic‐ferromagnetic‐ferrimagnetic quaternary alloy (QA) is constructed on the Bethe lattice. • The QA is taken in the compound form as ABpCqDr and formulated in terms of exact recursion relations. • The randomization is applied in the standard‐random approach. • The A, B, C and D atoms are taken as spin‐1, spin‐3/2, spin‐5/2 and spin‐2, respectively. • The phase diagrams are studied from the thermal analysis of the order‐parameters. [ABSTRACT FROM AUTHOR]

By using Monte Carlo simulations for classical Heisenberg spins, we study the critical phenomena and ferrimagnetic properties of spherical nanoparticles with core-shell geometry. The particle core is composed of ferromagnetic spins, and it is coated by a ferromagnetic shell. Total size of the particle is fixed but the thickness of the shell is varied in such a way that the shell layer is grown at the expense of the core. Effects of the shell thickness, as well as dynamic magnetic field parameters such as oscillation period and field amplitude on the magnetization profiles, dynamic hysteresis loops and phase diagrams have been investigated for the present system. It has been found that as the shell thickness varies then the easy axis magnetization of the overall system may exhibit Q -, P -, L - and N - type behaviors based on the Neél terminology. We also found that three distinct anomalies originate in the thermal variation of specific heat with increasing field period. Dynamic hysteresis loops corresponding to off-axial magnetization components exhibit unconventional behavior such as double rings with symmetric shapes around the vertical axis over the h ( t ) = 0 line which may originate due to the stochastic resonance behavior of these components. [ABSTRACT FROM AUTHOR]

The hysteresis properties and phase diagrams of a ternary nanowire, composed of a ferromagnetic (FM) core of spin-1 encircled by a ferrimagnetic (FiM) shell of mixed spin-(1/2, 3/2). Monte Carlo simulation is used to study the effects of the exchange interactions (R s , R 1 , R 2 and R I F) and crystal fields (D c , D s) on the phase diagrams for various thicknesses of core and shell of the system. Our outcomes indicate that the compensation temperature exists for a particular range when D c and D s are present. In addition, a first and a second order phase transitions appear for different values of D c , while a second phase transition appears for various values of D s. Moreover, the hysteresis loops, coercivities and remanences of the system and three sublattices are discussed in detail. Multiple hysteresis loops such as double, triple and quintuple loops were found in the system for a various physical parameters. By comparing our findings to those of previous theoretical and experimental studies, a qualitative agreement can be found. [ABSTRACT FROM AUTHOR]

In this paper, the magnetic properties of a bi-layer graphyne structure have been studied using Monte Carlo simulations. The considered system is composed of two planes of graphyne with mixed spins: σ = 7/2 and S = 1. Firstly, the ground state phase diagrams for zero temperature are reported and discussed. Secondly, the magnetic properties for the studied system are examined for non-zero temperature. The effects of exchange coupling interaction and temperature on magnetization, susceptibility and transitional temperature. Furthermore, the effects of the crystal field on total magnetization of the system have been exhibited. Finally, the effect of the ferrimagnetic parameter, temperature and crystal field on the hysteresis cycles have been determined. The obtained results have been compared with theoretical and experimental researches. • We study the magnetic properties of a bi-layer graphyne structure. • The ground state phase diagrams are presented and discussed. • The magnetic properties of a bi-layer graphyne structure using Monte Carlo simulations are investigated. • The hysteresis cycles of a bi-layer graphyne structure are analyzed. [ABSTRACT FROM AUTHOR]