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In this study, a bilayer zigzag graphyne nanoribbon with RKKY interaction is described using a ferrimagnetic mixed-spin (2, 5/2) Ising model. The compensation behaviors and hysteresis characteristics of the system generated by various physical parameters, such as crystal fields of sublattices, interlayer exchange coupling and the intralayer exchange coupling are explored using Monte Carlo simulation. In the research results, we found that among the 30 possible spin configurations that may occur in the ground state of the system, only 21 spin configurations are stable. At the same time, under certain parameters, the system exhibit interesting behaviors such as compensation phenomena and multi-loop hysteresis. This can provide a theoretical reference for multi-state magnetic recording. • Ising model and Monte Carlo method were used to study the bilayer zigzag graphyne nanoribbon. • The effect of RKKY interaction on the magnetic properties of the graphyne was investigated. • The ground-state phase diagram, magnetization, magnetic susceptibility were obtained. • Phase diagrams and hysteresis loop of the system were presented. • Interesting behaviors of compensation temperatures and multi-loop hysteresis were found under certain parameters. [ABSTRACT FROM AUTHOR]

• 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]

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]

Abstract Based on the Ising model, the magnetic and thermodynamic properties of a ferrimagnetic mixed-spin (1/2, 1, 3/2) nanoisland with a double-layer quadrangle core-shell structure has been investigated by Monte Carlo simulation. The magnetization of the total system and three sublattices, susceptibility, blocking temperature, internal energy and hysteresis loops have been discussed in detail. The phase diagrams of the T B under the influence of various parameters have been given. We have obtained the critical exponents β and γ for the system. Multiple hysteresis loops behaviors such as single, triple, quintuple and septuple loops have been found, originating from the competitions among various parameters. The results are comparable with some theoretical and experimental studies given in advance. Highlights • The ferrimagnetic mixed-spin (1/2, 1, 3/2) nanoisland in the longitudinal magnetic field has been investigated. • Magnetization, susceptibility, internal energy and blocking temperature have been discussed. • The multiple hysteresis behaviors such as single, triple, quintuple and septuple loops have been obtained. [ABSTRACT FROM AUTHOR]

The magnetic properties of the mixed spin-1 and spin-5/2 Ising ferrimagnetic model on a hexagonal lattice have been studied using the Monte Carlo simulations. The hexagonal lattice study is formed by alternate layers of spins σ = 1 and S = 5 ∕ 2 . The thermal variations of the magnetizations are given. The magnetic hysteresis cycles are established for different values of exchange interactions, crystal-field and temperatures. The magnetic coercive field is deduced. [ABSTRACT FROM AUTHOR]

Monte Carlo simulation is used to study the magnetic properties of mixed spin (3/2, 1) disordered binary alloys on simple cubic, hexagonal and amorphous magnetic ultra-thin films with 18 × 18 × 2 atoms. To this end, at the first approximation, the exchange coupling interaction between the spins is considered as a constant value and at the second one, the Ruderman–Kittel–Kasuya–Yosida (RKKY) model is used. Effects of concentration, structure, exchange interaction, single ion-anisotropy and the film size on the magnetic properties of disordered ferromagnetic and ferrimagnetic binary alloys are investigated. Our results indicate that the spontaneous magnetization and critical temperatures of rare earth-3 d transition binary alloys are affected by these parameters. It is also found that in the ferrimagnetic state, the compensation temperature ( T com ) and the magnetic rearrangement temperature ( T R ) appear for some concentrations. [ABSTRACT FROM AUTHOR]

Magnetic properties of mixed spin (3/2, 1, 1/2) ferro-ferrimagnetic ternary alloys of the type A y ( B x C 1 − x ) 1 − y are investigated, by means of the Monte Carlo simulation. For this purpose, the influence of concentration, temperature and an external magnetic field on magnetization, magnetic hysteresis loop, magnetic susceptibility and specific heat of ternary alloys with amorphous structures are examined. We found that the compensation temperature exists for some concentrations. Also, it is observed that these ferrimagnetic ternary alloys indicate double hysteresis loop which have been seen theoretically and experimentally in different magnetic alloys. The thermal behavior of magnetization, hysteresis loop and specific heat are also investigated. [ABSTRACT FROM AUTHOR]

A hexagonal nanowire consisting of a ferromagnetic spin– 1 2 core and spin– 3 2 outer shell coupled with ferrimagnetic interlayer coupling has been studied by the use of the Monte Carlo simulation based on the heat bath algorithm. Particular emphasis is given to the effects of the size, the crystal field, the shell and the interface coupling constants on the critical and the compensation phenomenon. Some interesting behaviors have been observed which include the first and second order phase transitions. The isolated critical points are also observed. We have also found that the system exhibits the compensation phenomenon for appropriate values of the system parameters. The critical exponent has also been calculated. [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 magnetic properties of ferrimagnetic spin-2 and 3/2 Ising-typed thin films are studied by Monte Carlo simulation. The critical temperature is obtained for different values of thickness of the thin film and for different exchange interactions. The total magnetization has been determined for different values of exchange interactions in surface and in bulk and different temperatures. The magnetic hysteresis cycle is obtained for different values of exchange interactions ferro and antiferromagnetic in the surface and in the bulk and for different values of temperatures for a fixed size of the film thickness. The coercive field increase with increasing the film thickness. [ABSTRACT FROM AUTHOR]

We performed the Monte Carlo simulation (MCs) in order to study the magnetic properties and the critical behavior of Sr 2 CrMoO 6 . Within this magnetic oxide, the Cr 3+ and Mo 5+ ions form two interpenetrating ferromagnetic sublattices with opposite spins directions (Cr 3 + up and Mo 5+ down). The exchange interaction between these sublattices is assumed to be ferrimagnetic. The effects of the system parameters on critical temperatures and as a result on the phase diagrams are shown by using reduced values of parameters. The phase transitions and the magnetic stability are investigated in the framework of Ising model. For specific values of the system parameters, the existence of a compensation point is shown. Furthermore, to investigate the critical behavior, the critical exponents are calculated, they indicate that the compound belongs to a three dimensional Ising universality class. The reduced transition temperature is also found. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we have used Monte Carlo Simulation technique (MCS) and effective field theory (EFT) to study the critical and the compensation behaviors of a ferrimagnetic cylindrical nanowire. The system consists of a ferromagnetic spin S A =1/2 core and a ferromagnetic spin S B =1 surface shell coupled with an antiferromagnetic interlayer coupling J 1 to the core. The effects of the uniaxial anisotropy, the shell coupling and the interface negative coupling on both the critical and compensation temperatures are investigated. [Copyright &y& Elsevier]

Abstract: A Monte Carlo Simulation has been used to study the critical behavior of the magnetic spin-1 Ising nanowire on an hexagonal lattice structure. Our system consists of a ferromagnetic core with two shells, coupled antiferromagnetically with a surface shell. The effects of the crystal field, the shell and the core/shell interactions on the behavior of the system are examined. We found that the system exhibits one or two compensation points, the first and the second order transitions. Moreover, we have obtained that the critical point depends on the shell coupling. [Copyright &y& Elsevier]

In this paper, we have examined in detail the behavior of magnetic properties, hysteresis loops, and compensation phenomenon of a ferrimagnetic mixed spin- (3 ∕ 2 , 2) hexagonal Ising nanowire with alternate layers within the Monte Carlo method based on the Metropolis algorithm. The effect of longitudinal crystal field and exchange coupling constants on the total and the sublattice magnetizations, susceptibilities, specific heat, internal energy, as well as hysteresis loops are investigated for particular parameters. The obtained résults showed different interesting magnetic phenomena, such as seven and triple hysteresis loops at low temperatures, and one or double compensation temperatures under certain parameter values. Our outcomes are also compared with various experimental and theoretical studies. • A hexagonal mixed spin-3/2 and spin-2 Ising ferrimagnetic nanowire with alternate layers, within Monte Carlo simulation techniques. • The effects of the longitudinal crystal fields, the exchange coupling constant, and the temperature on the thermodynamic and magnetic properties and the hysteresis loops were examined in detail. • The seven and triple hysteresis loops at low temperatures, and double compensation temperatures under certain physical parameters. [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]

In this work, we discussed the dynamic magnetic behaviors of a ferrimagnetic mixed spin-1 and spin-3/2 Ising ladder-type graphene nanoribbon in a time-dependent magnetic field by utilizing Monte Carlo simulation. The influence of exchange couplings, crystal-field, time-dependent oscillating magnetic field as well as temperature on the magnetic properties and hysteresis behaviors of the system was studied in detail. Various curves of the dynamic order parameter, susceptibility and internal energy of the system and hysteresis loops were obtained for different Hamiltonian parameters. What is striking is that the system may display double-loop hysteresis behavior under certain parameters. An Ising model of ladder-type graphene nanoribbon is proposed and multiple saturation values of the total dynamic order parameter are found in the system. [Display omitted] F0B2 • A ferrimagnetic mixed spin Ising ladder-type graphene nanoribbon was studied under a time-dependent magnetic field. F0B2 • The dynamic order parameter, the susceptibility and the internal energy were discussed by Monte Carlo simulation. F0B2 • The phase diagrams and the double-loop hysteresis behavior were obtained. [ABSTRACT FROM AUTHOR]

Magnetic and thermodynamic properties of the zigzag graphene nanoribbon described by Ising model have been studied within Monte Carlo simulation. The system exhibited interesting and rich magnetization plateaus behaviors at low temperature, which is sensitive to the exchange coupling and the anisotropy. In certain parameters, the depressed saturation magnetization, spin-flip or spin-flop has been found on the magnetization curves. The peaks on the susceptibility and specific heat curves originate from competition among the magnetic field, the exchange couplings and anisotropies. The spin configurations of the zigzag graphene nanoribbon can be modulated by the anisotropies. Our results can provide an opportunity for the design of a new type random access memory by using zigzag graphene nanoribbon. • Ising model of zigzag graphene nanoribbon is suggested. • Magnetic properties of the system have been studied. • spin-flip or spin-flop has been found on the magnetization curves. [ABSTRACT FROM AUTHOR]