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The paper presents a study on the magnetic characteristics of hexagonal boron nitride using Monte Carlo simulations through the Metropolis algorithm. The study used the Blume-Capel Ising model to analyze the behavior of magnetizations and susceptibilities under the effect of the temperature, mixed exchange coupling, crystalline and external magnetic fields. The results show that the blocking temperature, where the magnetic atoms become magnetically frozen, increases as the exchange coupling interaction becomes weaker and as the external magnetic field increases. The findings indicate that the blocking temperature of the system is significantly influenced by the physical parameters employed in this study. Besides, the investigation at hand could serve as a foundation for researchers to innovate novel categories of spintronics and magnetic memory devices, featuring enhanced performance and functionality. [ABSTRACT FROM AUTHOR]

Using Monte Carlo simulations under the Metropolis algorithm, the magnetic properties of a Mixed Spins (3/2, 1) cubic lattice modeled by mixed spin Ising model have been investigated. First, we discuss the ground state phase diagrams at zero temperature corresponding to different parameters of the model. Then, by choosing ferrimagnetic phases found in the obtained phase diagrams, we analyze the magnetization and compensation behaviors in our system. Striking results have been found; especially, the competition between exchange coupling interactions generates a critical temperature T C and a compensation temperature T comp with T comp < T C . Moreover, the presence of crystal and external magnetic fields leads to the appearance of a second compensation temperature with T c o m p 1 < T c o m p 2 ≪ T C . [ABSTRACT FROM AUTHOR]

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]

The ability to tune and control the magnetic phases of two-dimensional (2D) nanomagnets at room temperature is indispensable for the development of future spintronics and low-dimensional spin circuits. In this work, a first-principles-based investigation combined with a Monte Carlo simulation based on a 2D Ising model is used to investigate the electronic and magnetic behaviour of a recently discovered 2D material, Cr2Ge2Se6 over a large range of strain and electric field strength. This material offers ferromagnetic antiferromagnetic and semiconductor metallic phase transitions in different regimes. In the presence of strain, a colossal enhancement of the critical temperature (Tc) is observed, from 149 K to 885 K. The application of an electric field allows a further enhancement of the Tc to a value of 919 K, offering a supreme enhancement (~517%), compared to its natural condition. The origin of this behavior can be traced to a super-exchange interaction between the Cr and Se atoms and the intrinsic magnetic anisotropy of Cr2Ge2Se6. The presence of external stimuli engenders spontaneous symmetry breaking with an enhanced magnetic moment (~4.36 /Cr atom), a significant intrinsic spin polarisation (~100%) in a half-metallic regime, and a very high critical temperature. The insights of the current investigation could be useful for future developments in multi-stimuli-assisted room-temperature ferromagnetism and electronic phase control, which are of great significance for future magneto-electronic applications. [ABSTRACT FROM AUTHOR]

The antiperovskite Co4N is studied using density functional theory (DFT) calculations and Monte Carlo (MC) simulation within the framework of the Ising model. The structural, density of states (DOS), and band structure calculations show that Co4N is a ferromagnetic material having a higher magnetic moment, a large spin polarization ratio, and exhibits a metallic behavior. The investigated elastic constants, phonon dispersion, and phonon DOS show that the Co4N compound is mechanically and dynamically stable. It is also found that the Co4N is ductile from the Poisson's ratio, Pugh's ratio, and Cauchy pressure. The thermodynamic parameters like heat capacity, Debye and melting temperature are calculated. The magnetization, magnetic susceptibility, and the Curie temperature of magnetic transition are estimated using MC simulations based on the Ising model. The obtained value of TC is in good agreement with available theoretical work. [ABSTRACT FROM AUTHOR]

A mixed-spin (5/2, 3/2) Ising model is established to describe the antiferroelectric/ferroelectric (AFE/FE) BiFeO 3 /Co bilayer structure. We study the effects of the crystal field, exchange coupling and external longitudinal electric field on the dielectric properties of the bilayer based on Monte Carlo simulation. We illustrate the temperature dependence of polarization, susceptibility, internal energy and specific heat of the system in detail. As well, we depict the phase diagram and point out the rule of the blocking temperature with various parameters. In particular, we find rich and interesting multi-cycle electric hysteresis behaviors. The results show that these parameters play a crucial part in the physical properties of the AFE/FE BiFeO 3 /Co bilayer structure. [ABSTRACT FROM AUTHOR]

We have employed first-principles calculations of density functional theory (DFT) with GGA and GGA+U exchange correlation to study structural, magnetic, and electronic properties of chromium nitride (CrN) in the rock salt (NaCl) structures. The obtained data from DFT calculations is used as an input in high-temperature series expansions (HTSEs) combined with the Padé approximants (PA) method and Monte Carlo simulation (MC) for the Ising model to investigate the magnetic properties of CrN. The obtained results show that CrN is more stable in the antiferromagnetic order, and undergoes structural and magnetic transitions from an antiferromagnetic NaCl structure to a nonmagnetic Pnma phase at 201 GPa. The density of states (DOS) with GGA approach shows that CrN has a metallic behavior in both FM and AFM configurations whereas with GGA+U CrN is semiconductor in AFM and half-metallic in FM order. The Neel temperature (TN) obtained by HTSE and MC is in agreement with available experimental data. [ABSTRACT FROM AUTHOR]

In this paper, we have studied the structural, electronic, and magnetic properties of the cubic perovskite system Mn4N using the first principles calculations based on density functional theory (DFT) with the generalized gradient approximation (GGA). The obtained data from DFT calculations are used as input data in Monte Carlo simulation with a mixed spin-5/2 and 1 Ising model to calculate the magnetic properties of this compound, such as the total, partial thermal magnetization, and the critical temperatures (TC). The obtained results show that Mn4N has a ferrimagnetic structure with two different sites of Mn in the lattice and presents a metallic behavior. The obtained TC is in good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Critical behavior and magnetic properties of La0.67Sr0.33MnO3 (symbolized as LS33MO) have been studied by means of Monte Carlo simulation (MCS). By using the heat-bath algorithm and the Ising model up to third nearest neighbor exchange interactions, we have computed the magnetic and magneto-caloric properties. The effects of the temperature (T) and the external magnetic field (h) on the magnetic behavior of LS33MO have been discussed. The results demonstrate that the Curie temperature (TC) is close to the experimental value. The magnetic entropy shows a maximum value around TC which increases linearly with the rise of the external field h. For h = 5T, the maximum entropy (∆ S m max ) is about 3.67 J K−1 kg−1 which is in good agreement with the experimental results. The relative cooling power (RCP) has been estimated and it has been found that it increases with respect to the external field. The predicted critical behavior has been studied by isothermal magnetization of LS33MO nanoparticle compound. The critical exponents (Crt.Exps) are determined by various approaches, such as the modified Arrott plot (AP) and critical isotherm ways. Therefore, the Crt.Exp values obtained by different techniques are β = 0.306, γ = 1.178, and δ = 4.025 respectively. The trustworthiness of the values of the Crt.Exp was approved by the Widom scaling equation and the universal scaling hypothesis. [ABSTRACT FROM AUTHOR]

In the presence of the crystal field D/JCore and the external magnetic field h/JCore, using the Monte Carlo (MC) simulation based on the heat bath algorithm and the effective field theory (EFT), the triangular mixed spin nanowire model consisting of a spin-(1/2) core which is encircled by a spin-1 ferrimagnetic surface shell is studied. We have studied the special effects of the core surface and crystal field on the critical and compensation temperatures. Several properties, such as the magnetization, hysteresis behaviors, coercive field, and remanent magnetizations are studied. For the appropriate values of the system parameters, the compensation point and multi-loops are found PACS 05.50. + q; 77.80. Bh. [ABSTRACT FROM AUTHOR]

The effects of single-ion anisotropies and an external magnetic field on the magnetization of the mixed-spin (7/2, 3/2) ferrimagnetic Ising system are investigated within Monte Carlo simulation. Under certain values of the physical parameters, multiple hysteresis loop behaviors such as double, triple, and quintuple hysteresis cycles have been observed. Particularly, the superparamagnetic phase has been shown. The ground-state phase diagrams are presented. [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]

We proposed a ferrimagnetic mixed-spin (1, 3/2) Ising model to study the magnetic behaviors of a graphene ladder-type chain structure by means of Monte Carlo simulation. Induced by different physical parameters, the system can display interesting magnetic behaviors such multiple saturation magnetization values, double-peak susceptibility curves, and multi-cycle hysteresis loops. The results illustrate that crystal-field, exchange coupling and external magnetic field show significant impacts on the magnetic properties of the system. • A mixed-spin (1, 3/2) Ising model was proposed to describe a ferrimagnetic graphene ladder-type chain structure. • Magnetization, magnetic susceptibility, and internal energy were studied by Monte Carlo method. • The phase diagrams of the blocking temperature in three-dimensional space was given. • Multi-cycle hysteresis behaviors were discovered caused by various parameters. [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]

The magnetic properties of multilayered with alternating magnetic wires with the mixed spins-2 and 5/2 ferrimagnetic Ising model have been studied using the Monte Carlo simulations. We have given the ground state phase diagrams of a mixed Ising model on a multilayered with alternating magnetic wires with the mixed spins S (±2, ±1,0) and σ(±5/2, ±3/2,±1/2). The proposed Hamiltonian includes exchange interactions, crystal field and external magnetic field. The reduced transition temperature is deduced for a fixed value of layers. The effect of the exchange interactions and the crystal field on the magnetization of several layers has been investigated for a fixed values of layer with spin-3/2 and varying the layer values with spin-2. Magnetic hysteresis cycles of multilayered with alternating magnetic wires with the mixed spins-2 and 5/2 ferrimagnetic Ising model for several of exchange interactions between the mixed spins (S and σ), sizes of layers and temperatures values have been established. [ABSTRACT FROM AUTHOR]

We study the thermodynamic and magnetic properties of an Ising bilayer ferrimagnet. The system is composed of two interacting non-equivalent planes in which the intralayer couplings are ferromagnetic while the interlayer interactions are antiferromagnetic. Moreover, one of the planes is randomly diluted. The study is carried out within a Monte Carlo approach employing the multiple histogram reweighting method and finite-size scaling tools. The occurrence of a compensation phenomenon is verified and the compensation temperature, as well as the critical temperature for the model, are obtained as functions of the Hamiltonian parameters. We present a detailed discussion of the regions of the parameter space where the compensation effect is present or absent. Our results are then compared to a mean-field-like approximation applied to the same model by Balcerzak and Szałowski (2014). Although the Monte Carlo and mean-field results agree qualitatively, our quantitative results are significantly different. [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 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]

A Monte Carlo simulation based on Metropolis algorithm has been used to investigate the magnetic properties of an Ising ferrimagnetic nanowire on a hexagonal structure, which is made up with L alternate layers of spins σ = ±3/2, ±1/2 and S = ±1, 0. The critical behaviors are studied, in the absence as well as in the presence of crystal field interactions. The obtained results show the existence of some interesting phenomena, such as the appearance of different types of phase diagrams. Furthermore, tricritical point, isolated critical point, critical end point, and compensation behavior are found for appropriate values of the system parameters. [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]

• 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]

Monte Carlo simulation has been used to study the magnetic properties of a mixed spin-1 and spin-3/2 ferrimagnetic through Ising model on a honeycomb lattice. The total magnetization, magnetization of sublattice A with spin 1 and sublattice B with spin 3/2 are studied for different values of exchange interactions, for a zero crystal field and for different values of a magnetic field. The total magnetization versus the exchange interactions J AB / J AA for different values of crystal field of two sublattices is given. Magnetic hysteresis cycles of system and sublattices are given for different values of exchange interactions and crystal field. [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]

Monte Carlo simulation has been employed to investigate the magnetic properties and phase diagrams of ferrimagnetic mixed-spin (1 / 2 , 1) triangular Ising nanotube with core–shell structure. In particular, the effect of the exchange couplings and the temperature on the magnetic and thermodynamic properties, hysteresis loops, and the compensation temperature have been discussed in detail. Moreover, the effects of the single-ion anisotropy and external magnetic field have been examined. The threshold values of the exchange couplings and single-ion anisotropy have been found, determining whether the system exhibits a compensation temperature. We have found that the appearance of the compensation temperature is strongly linked with the system parameters. Moreover, we have obtained the double and triple hysteresis loops for certain physical parameters in the magnetic system. [ABSTRACT FROM AUTHOR]

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]

We applied Monte Carlo simulation to investigate the thermodynamic properties and hysteresis loops of the hexagonal core-shell nanoparticle described by a ferrimagnetic mixed-spin (3/2, 5/2) Ising model. The results revealed the significance of the single-ion anisotropy, exchange coupling, external magnetic field in dominating various thermodynamic quantities and hysteresis loops. We obtained the variation of the critical temperature with various parameters. Under certain parameter conditions, the system may exhibit rich multiple-loop hysteresis behaviors, depending on the competition among the physical parameters. An Ising model of nanoparticle with hexagonal core-shell structure is proposed. The multiple profiles and saturation values of the magnetization are discovered in the system. [Display omitted] • A ferrimagnetic hexagonal core-shell nanoparticle was proposed under an external magnetic field. • Magnetization, susceptibility, and internal energy were discussed by Monte Carlo simulation. • The compensation temperature was found under the effect of single-ion anisotropy. • Multiple-loop hysteresis behaviors were discovered due to the competition among different 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]

• We study a frustrated general spin-S Ising antiferromagnet on a kagome lattice. • We explore possibility of long-range ordering for any finite or infinite values of S. • Character of the spin-correlation function is studied by Monte Carlo simulations. • It is found that system remains disordered for any spin S and any finite temperature. The possibility of the emergence of some kind of long-range ordering (LRO) due to the increase of multiplicity of the local degrees of freedom (spin value S) is studied in an Ising antiferromagnet on a kagome lattice (IAKL) by Monte Carlo simulation. In particular, the critical exponent of the spin correlation function, obtained from a finite-size scaling analysis, is evaluated for various values of S , including S = ∞ , with the goal to determine whether there exists some threshold value of the spin S C above which the system would show true or quasi-LRO, similar to a related model on a triangular lattice (IATL). It is found that, unlike in the IATL case, the IAKL model remains disordered for any spin value and any finite temperature. [ABSTRACT FROM AUTHOR]

The double perovskite Ba 2 FeMnO 6 is studied by using density functional theory calculations and Monte Carlo simulation within the framework of the Ising model. Based on the minimum energy, the structure was optimized and the stable configuration of spins in Ba 2 FeMnO 6 double perovskite was determined. The magnetic moments, the band structure and the electronic density of states (DOS) were analyzed in details. The oxide Ba 2 FeMnO 6 exhibits a half-metallic behavior with a band gap close to the value 0.3 (eV). The stable spin configuration is considered for the Monte Carlo simulation. A first order transition and a compensation behavior have been found. • Electronic and magnetic properties of Ba 2 FeMnO 6 are studied by DFT and MCS. • Stable configuration of spins in Ba 2 FeMnO 6 was determined. • Ba 2 FeMnO 6 exhibits a half metallic behavior and a magnetic moment μ = 4. 406 μ B . • Compensation behavior and first order transition have been found. [ABSTRACT FROM AUTHOR]

• Critical properties of Fe-Al alloys in the bcc phase – phase diagram. • Ising model with exchange and superexchange interactions. • Monte Carlo simulations taking the effects of the Al cluster sizes. A spin-1/2 Ising model, defined in the body centered cubic lattice, is used to describe some of the thermodynamic properties of Fe p - Al q alloys, with p + q = 1. The model assumes, besides the nearest-neighbor exchange coupling, the existence of further next-nearest-neighbor superexchange interactions, where the latter ones depend on the aluminum atoms cluster size. The Ising system so considered is studied by employing Monte Carlo simulations, using a hybrid algorithm consisting of one single-spin Metropolis move together with one single-cluster Wolff algorithm allied, in addition, with single histograms procedures and finite-size scaling techniques. Quite good fits to the experimental results of the ordering critical temperature, as a function of Al concentration in the range 0 ⩽ q < 0.7 , are obtained and compared to more recent theoretical approaches done on the same alloys. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a ferrimagnetic mixed-spin (1, 3/2) Ising model to describe the ladder-like graphene nanoribbon. Using the Monte Carlo simulation, the effects of the anisotropies, exchange couplings, longitudinal magnetic field and temperature on the magnetic and thermodynamic properties were investigated. Typical temperature dependences of thermodynamics quantities such as magnetization, susceptibility and internal energy were presented under the influence of various physical parameters. The phase diagrams of blocking temperature were obtained in the different parameter planes. In particular, we also found some interesting double hysteresis loops behavior for certain physical parameters. Our results are consistent with those obtained by some theoretical and experimental researches. • The ferrimagnetic mixed-spin (1, 3/2) Ising ladder-like graphene nanoribbon in the longitudinal magnetic field has been studied. • Magnetization, susceptibility and internal energy have been discussed. • The phase diagrams of the blocking temperature under the influence of different parameters have been obtained. • The double hysteresis loops behavior has been found for certain physical parameters. [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]