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We used Monte Carlo simulation to study the magnetic properties and compensation behavior of a ferrimagnetic mixed-spin (3 / 2 ; 1 / 2) Ising system in a graphene bilayer. The effects of exchange interactions, crystal field, external magnetic field and temperature on the total magnetization, partial magnetizations, magnetic susceptibility, phase diagram and hysteresis behavior of the system were examined. Interesting results were obtained in this work, such as the compensation behavior and the multi-loop hysteresis phenomenon for specific values of the system's physical parameters. Our results conform to those of other theoretical studies. • The compensation and critical behaviors of a Graphene Bilayer were investigated. • Different total magnetization profiles are observed in this ferrimagnetic system. • The effect of various physical parameters on hysteresis behavior was presented. [ABSTRACT FROM AUTHOR]

Using DFT and Monte Carlo simulation, we studied the physical properties of the ferrimagnetic half-metal Mn 2 RhSi Heusler alloy. Our calculations reveal a stable face-centered cubic structure without any possibility of martensitic transition. The electronic structure shows half-metallic behavior with a band gap in spin-down of 0. 49 eV calculated using PBE and 0. 85 eV using the r 2 SCAN functional, and antiferromagnetic–ferromagnetic coupling with a Curie temperature of 460 K. The elastic constants and moduli decrease with temperature due to thermal expansion, but Mn 2 RhSi retains its mechanical stability. The dominance of metallic bonds, large band gap, high Curie temperature, low magnetic moment, and good mechanical properties make Mn 2 RhSi a promising candidate for spintronic applications at room temperature. • Mn 2 RhSi is an inverse Heusler ferrimagentic half-metal. • According to the r2SCAN functional, Mn 2 RhSi has a spin-down gap of 0.85 eV. • Curie temperature of Mn 2 RhSi calculated using Monte Carlo simulation is 460 K. • Mechanical properties indicate that Mn 2 RhSi is mechanically stable and ductile over the temperature range of 0–1000K. • The wide gap and Curie temperature above room temperature suggest that Mn 2 RhSi can be suitable for spintronic applications. [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 mean-field approximation based on the Gibbs-Bogoliubov inequality and Monte Carlo simulations based on the Metropolis method in the Blume–Emery–Griffiths model were used to successfully examine a hexagonal Ising nanowire with spin-1. It was found that the model displays fascinating phase diagrams in various planes of interest by using both methods. The investigation of magnetic hysteresis cycles also exhibits interesting properties. The model not only presents first- and second-order phase transition lines, but also the tricritical and isolated critical points, multi-compensation temperatures, and magnetic hysteresis behavior with one to eight cycles. • The mean-field approximation based on the Gibbs-Bogoliubov inequality is applied. • The Monte Carlo simulations based on the Metropolis method is employed. • Spin-1 Blume–Emery–Griffiths model for hexagonal Ising nanowire is investigated. • First- and second-order transitions, tricritical and isolated critical points are found. • Multi-compensation and magnetic hysteresis with one to eight cycles are observed. [ABSTRACT FROM AUTHOR]

This study investigates the magnetocaloric potential of the Al 50 Cr 21-x Mn 17+x Co 12 (x=0, 4, 8 at%) high-entropy alloy (HEA) series using integrated experimental and theoretical approaches. Structural analysis by X-ray diffraction and scanning electron microscopy indicate a dual phase containing B2 and body-centered cubic (BCC) structures. Magnetic characterization shows an approximately linear decrease in saturation magnetization and Curie temperature with increasing Cr content. Curie temperatures calculated by Monte Carlo simulations suggest that the measured magnetic properties originate from the B2 phase rather than the BCC phase. The enhanced magnetocaloric effect with decreasing Cr content highlights the attractiveness of HEAs in magnetocaloric applications. • Al 50 Cr 21-x Mn 17+x Co 12 (x=0, 4, 8 at%) high-entropy alloys were prepared by arc melting. • The phase and chemical composition analysis indicates a dual phase containing B2 and BCC structures. • Calculated T C s suggest that the measured magnetic properties originate from the B2 phase rather than the BCC phase. • Tunable TC and magnetization with decreasing Cr were confirmed through measurement of TC and hysteresis loops. • The magnetocaloric effect was quantified by measuring the adiabatic temperature change and magnetic entropy change. [ABSTRACT FROM AUTHOR]

The influence of external pressures on the structural and magnetic properties of the FeNi alloy is elucidated using density functional theory (DFT) and Monte Carlo simulation. Utilizing a range of pressures, the study showcases compressive behavior in lattice constants, with both a and c exhibiting reductions. A sharp decline in magnetic moments is recorded at a critical pressure of 54 GPa. Indicating a magnetic phase transition from ferro to paramagnetic phase. Beyond this critical pressure, dynamical instability becomes evident, attributable to the aforementioned magnetic phase transition. Further examination of exchange interaction parameters reveals that while Fe–Fe interactions exhibited a consistent decrease with pressure, the FeNi and NiNi interactions remained relatively stable across the examined pressure range. At pressures close to 0 GPa, the Curie temperature (T C) was found to be around 838 K. As the external pressure is applied, a consequential decline in T C is witnessed, suggesting a significant sensitivity of the magnetic phase transition to external pressures. In particular, this study indicates that the FeNi alloy is sensitive to external pressures, emphasizing some relation between structural and magnetic properties. [Display omitted] • A comprehensive examination of the influence of external pressure on the properties of the FeNi alloy has been conducted. • A magnetic phase transition from a ferromagnetic to a paramagnetic state has been observed at a critical pressure of 54 GPa. • There is a decrease in the Curie temperature as the applied external pressure is increased. [ABSTRACT FROM AUTHOR]

Ab initio calculations are used in the present study to analyze the structural, magnetoelectronic, mechanical, thermal, thermoelectric, optical and thermodynamic properties of AMnBi 2 compounds (where A = Ca and Sr). The calculations use the density functional theory involving the Full Potential –Linearized Augmented Plane. Wave and the Monte Carlo simulation. We have used the Generalized Gradient Approximation (GGA) with Perdew-Burke-Ernzerhof (PBE) functional for modelling the exchange-correlation potential with Hubbard correction (GGA + U) was employed. The bulk modulus, its first derivative, and the optimal lattice parameters have been found. Both compounds display metallic nature. The electronic transport coefficients have been calculated. The entropy, thermal expansion coefficient, Debye temperature, and heat capacities C v and C p are calculated. The elastic constants at zero pressure, the bulk modulus B, and the shear modulus G have been evaluated. The Young's modulus and Poisson's ratio of two compounds have been performed. The Debye temperature is also approximated from the average sound velocity. The Néel temperature, magnetization, and hysteresis cycles are found. [ABSTRACT FROM AUTHOR]

Exploring valley-contrasting physics in scarce intrinsic high-temperature ferromagnetic semiconductors with feasible synthesis route is of great significance for ever-evolving moden information technology. By first-principles calculations, the TiInTe 3 monolayer is predicted to demonstrate excellent structural stability and easy-plane semiconducting ferromagnetism arising from indirect superexchange mechanism. Monte Carlo simulations based on the Heisenberg model reveal a magnetic phase transition at 583 K well above room temperature. Due to the inversion and time-reversal asymmetries, tunable valley polarization in the conduction band up to 110 meV can be achieved by varying the magnetization orientation, which is further validated by a first-order perturbation theory. More excitingly, electron doping for realizing the anomalous valley Hall effect gives rise to an out-of-plane preference for magnetization in the TiInTe 3 monolayer and thus generates spontaneous and larger valley polarizations. After doping, the ferromagnetism above room temperature remains robust in the experimentally attainable electron density regime. Our findings highlight that the TiInTe 3 monolayer is a promising ferrovalley material for developing high-performance spintronic and valleytronic nanodevices. [Display omitted] [ABSTRACT FROM AUTHOR]

We report the structural stability and half-metallicity of the half-Heusler alloy CoMnSe via the density functional theory (DFT). The γ -phase ferromagnetic of CoMnSe is more energetically stable than other phases. The electronic and magnetic properties show that the CoMnSe is a false half-metal ferromagnetic with 98.10% spin polarization and a total magnetic moment of 4 μ B . This value is in good agreement with the Slater-Pauling rule and available data using the GGA method, whereas the GGA+U method shows it is a ferrimagnetic metal with 95.73% spin polarization, and the total magnetic moment is 4.01 μ B. The effects of Bulk strain and axial strain demonstrate that the relative change of total magnetic moment M t o t and spin polarization P of CoMnSe is almost negligible, indicating that the half-metallicity is strong against Bulk strain and axial strain. Using Monte Carlo simulations, a transition ferromagnetic-paramagnetic response is also studied. • CoMnSe alloy is mechanically and thermodynamically stable. • CoMnSe does not undergo martensitic transformation. • CoMnSe is found to be falsely half-metallic using GGA, while it is metallic using GGA+U. • The high spin polarization and Curie temperature make CoMnSe suitable for spintronic. [ABSTRACT FROM AUTHOR]

Due to interesting properties such as perpendicular magnetic anisotropy (PMA), ferrimagnetism, etc., rare earth-transition metal(RE-TM) alloys attract considerable attention in ultrafast and terahertz spintronics applications. The magnetic properties of RE-TM alloys strongly depend on their composition and vary with temperature. Here, we model crystallographically amorphous ferrimagnetic TbCo using atomistic spin dynamics(ASD) simulations to study their temperature dependence on magnetic properties by varying the compositions. In this study, we investigate the temperature dependence of magnetisation, uniaxial anisotropy, and coercivity values of amorphous Tb x Co 100 − x for the composition range Tb 18 Co 82 to Tb 36 Co 64. The monte carlo method is used to calculate the temperature dependence of magnetisation and calculate the magnetisation compensation temperature(T M) and curie temperature(T c) values for different compositions. The temperature dependence of uniaxial anisotropy is calculated from the angular dependence of free energy curves calculated at different temperatures using constrained monte carlo methods. Further, we evaluate the temperature dependence of coercivity values by calculating the magnetic hysteresis at different temperatures using the LLG Heun method. The results show the magnetic properties of amorphous TbCo can be easily tuned by varying their composition and have a strong temperature dependence. These highly tunable magnetic properties make them promising candidates for spintronics applications. [Display omitted] • RE-TM alloy thin films are interesting for ultrafast and terahertz spintronics applications. • RE-TM alloys are known for their intrinsic PMA, Ferrimagnetism and compensation temperatures. • The temperature dependence of M s , K u and H c of amorphous TbCo is studied using ASD simulations. • Magnetic properties of RE-TM alloys strongly depend on their temperature and composition. [ABSTRACT FROM AUTHOR]

A model for the description of atomic and magnetic ordering in Ni Mn Al shape memory alloys is presented. The parameters characterizing the energies of the chemical and magnetic interactions were obtained from fitting to experimental data. Monte Carlo simulations based on this model correctly reproduces the critical B 2 ↔ L 2 1 ordering temperatures as a function of composition for three pseudobinary composition lines, as well as the nature of the low temperature magnetic transition. A ferromagnetic configuration is predicted for alloys in the stable L 2 1 structure, whereas an antiferromagnetic state is obtained for metastably retained B 2 order; this is in agreement with experimental observations. It is verified that atomic ordering is strongly dominated by the interactions between Ni and Al atoms in nearest neighbours. As a consequence, the formation of B 2 order can delay the stabilization of the L 2 1 configuration at low temperatures. Since the magnetic interactions change sign with the Mn–Mn distance, the type of stable magnetic configuration depends on atomic ordering. • Atomic and magnetic ordering in Ni–Mn–Al alloys is studied by means of Monte Carlo simulations. • The critical B2-L2 1 temperatures are correctly reproduced for different compositions. • For L2 1 (B2) order a ferromagnetic (antiferromagnetic) state develops at low temperatures. • Variation of the order degree with temperature and composition is studied. [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]

In this paper, the ferrimagnetic mixed-spin (3/2, 5/2) Ising model was established to investigate the magnetic and thermodynamic properties of a nanoisland bilayer system with graphene-like structure by Monte Carlo simulation. We have analyzed the magnetization of the system and two sublattices, susceptibility, internal energy and hysteresis loops in detail. We have obtained the phase diagrams of the blocking temperature T B affected by the effects of various physical parameters. The triple hysteresis behavior has been observed, which originates from the competition among various physical parameters. Our results are comparable with those of other theoretical and experimental research. • The ferrimagnetic mixed-spin (3/2, 5/2) graphene-like nanoisland bilayer in the longitudinal magnetic field has been investigated. • Magnetization, susceptibility and internal energy have been discussed. • The phase diagrams of blocking temperature have been obtained under the influence of various physical parameters. • The triple hysteresis behavior have been found for certain physical parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] Modeling and simulation of microstructures are essential to understand the complex responses and behaviors of nuclear materials in extreme environments. The needs to assess the extended life operation as well as the growing interest in accelerating nuclear materials development and qualification have stimulated the use of high-fidelity multiscale models aided by empirical and ab initio data. This paper reviews the role of various models across different length and time scales in investigating irradiation effects on microstructure evolution and degradation, in particular the embrittlement caused by radiation induced or enhanced formation of nanoscale chemical heterogeneities. The strength and limitations of these models, including classical rate theories, cluster dynamics, phase-field methods, and atomistic models informed by ab initio energies, are discussed with seminal examples. Challenges regarding the lack of thermo-kinetic data and theoretical treatments considering chemical complexities and magnetic excitations, as well as the stabilizing effect by excess point defects in nuclear structural materials are presented, along with potential solutions based on ab initio informed surrogate energy models and statistical sampling by Monte Carlo simulations. The review then highlights the opportunities to leverage the advantages of different methods by establishing hybrid models by shared variables or coupled codes and applications. Finally, the review concludes with forward-looking remarks on how the use of physics-based models can aid the improvement of machine-learning models of property degradation and vice versa. [ABSTRACT FROM AUTHOR]

The band alignment, intrinsic ferromagnetism, Dzyaloshinskii-Moriya interaction, magnetic anisotropy and critical temperature (T C) of a GdI 2 /GeC van der Waals (vdW) heterostructure were systematically investigated by first-principles calculations and Monte Carlo simulations. The proposed GdI 2 /GeC vdW heterostructure is a bipolar magnetic semiconductor with Type-I band alignment, large in-plane magnetic anisotropy energy (MAE) of − 0.912 mJ/m2 and high critical temperature of 466 K. In addition, under biaxial strains, the heterostructure transformed from semiconductor into metal, while the easy magnetization axis maintained in-plane and T C increased. The results indicated that the GdI 2 /GeC vdW heterostructure presented large MAE and high T C , having potential applications in spintronic devices. [Display omitted] ● The heterostructures is a bipolar magnetic semiconductor. ● The heterostructures with large in-plane magnetic anisotropy. ● The heterostructures with high critical temperature 466 K. [ABSTRACT FROM AUTHOR]

The magnetic response of an identical magnetic nanoparticles (MNP) system to a rotating external field (RMF) is studied via Monte Carlo simulations. The field of amplitude H 0 and frequency ω , was applied in the y − z plane rotating clockwise. The energy was modeled by the Stoner–Wohlfarth scheme for fixed or random orientations of the anisotropy, and is in contact with a thermal bath at a temperature T. Interparticle dipolar interactions were also considered. In the non-interacting system and for low temperature, hysteresis is observed in the z magnetization component M z for both orientations of the anisotropy axis and only in the y component (M y) for the random case. Furthermore, the loop areas were estimated, and increased with ω for all orientations and ( M y , M z ) components. At higher temperatures the superparamagnetic state is observed, so both the blocking temperatures T B and loop areas were estimated. The values of T B were close from the room temperature T R = 300 K for all components, and the areas decreased with T but they are practically not zero at T B. When dipolar interactions are included a new scenario is revealed. In the low temperature regime, the blocked state is present for both M y and M z for all anisotropy orientations, and extends beyond the interval of amplitudes H 0 estimated theoretically for the model without interactions and fixed anisotropy. The loops are displaced with respect to the origin of the magnetization-external field plane. When the temperature is raised, the blocked state extends for a larger range than the model without interactions, and the loop displacement decreases with T. These behaviors could be explained by observing that the average dipolar field per particle produces an effective field – the sum of both dipolar and external field – that is asymmetric with respect to the zero field line at low temperatures, becomes half-wave symmetric at higher temperatures, so the the centered character of the loops is restored. In addition, the loop areas show a peak for all orientations of the anisotropy axes in an intermediate range of temperatures. This result can be associated with a dominance of the anisotropy induced by the dipolar field. Finally, by comparing the areas of the loops of the models with and without interactions, it was found that the non-interacting model have larger areas at low temperatures that vanish near the room temperature, unlike the areas of the model with interactions due to the extension of the blocked state. [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]

The magnetic characteristics of a mixed graphyne lattice were analyzed using the Monte Carlo method with the Metropolis algorithm at both low and high temperatures. This study examines the impact of temperature, crystalline field, external magnetic field, and strong coupling interaction on magnetic characteristics. Our results demonstrate that the magnetization plateaus depend strongly on both low temperature and crystal field variation. The results are consistent with previous theoretical and experimental studies. The multiple magnetization plateaus of the mixed graphyne lattice can have potential applications in multi-state memories. • The magnetic characteristics of a graphyne lattice are studied using Monte Carlo simulations. • The study investigates the impact of t different parameters on magnetic characteristics. • The study examines the transition temperature of different parameters.. [ABSTRACT FROM AUTHOR]

Organic coatings on magnetic nanoparticles are extensively used in various applications. As demonstrated recently, these coatings affect the magnetic behavior of the nanoparticles. The modification of the magnetic properties of the nanoparticles and nanoparticle assemblies as the percentage of the oleic acid (OA) coverage of a cobalt ferrite nanoparticle increases, is investigated numerically using a multiscale modeling approach that combines density functional theory (DFT) and Monte Carlo simulations. The DFT calculations show that the increase in OA coverage results in a monotonic decrease of the mean magneto-crystalline anisotropy and in a reduction of the atomic magnetic moments and the exchange coupling constants in the nanoparticle. These effects are attributed to the gradual recovery of the bulk spinel structure at the coated surface, as the OA coverage increases. Input from the DFT calculations is used in the mesoscopic modeling for the study of the magnetic behavior of an assembly of these nanoparticles by employing the Monte Carlo simulations technique. The results demonstrate that despite the decrease of magnetic anisotropy, the coercive field increases with the increase in percentage of OA coverage in the assembly, in agreement with experimental findings. This study suggests the possibility of tailoring the magnetic properties of cobalt ferrite nanoparticles for high-performance applications by varying the organic coating concentration. [Display omitted] • Tuning the magnetic properties of CoFe 2 O 4 nanoparticles by varying Oleic Acid coverage. • Multiscale modeling reveals OA concentration effect on CoFe 2 O 4 nanoparticles' magnetic behaviour. • Organic coating coverage gradually recovers the bulk magnetic behaviour in the nanoparticle. • Enhancement of the coercivity in partially OA coated Co ferrite nanoparticles assemblies. [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]

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]

The double perovskite Sr2CrIrO6 has very important characteristics for spintronic applications. It is a ferrimagnetic material distinguished by its high Curie temperature. This manuscript presents a model representing the double perovskite Sr2CrIrO6 in order to simulate and to predict its magnetic properties. This compound contains only two magnetic atoms, namely: Cr (S = 3/2) and Ir (σ = 2). Our simulations are done using the Monte Carlo method under the Metropolis algorithm. We present the behavior of the magnetization and the susceptibilities as a function of the temperature. Also, we discuss the effect of the physical parameters such as the coupling exchange interactions, the crystal field and the external magnetic field. To complete this study, we have presented the ground state by exposing the different phase diagrams in different planes of the physical parameters. Moreover, we establish the magnetic hysteresis loops of this compound. • We study the magnetic properties of the double perovskite Sr2IrCrO6. • We perform Monte Carlo simulations to investigate the magnetic properties of the double perovskite Sr2IrCrO6. • The effect of the physical parameters is studied and discussed. • The hysteresis loops are also presented for specific values of the physical parameters. [ABSTRACT FROM AUTHOR]

Abstract Using the dynamicMonte Carlo (DMC) simulation, the dynamic magnetocaloric effect of a ferrimagnetic C 70 Fullerene-like structure is studied within the dynamic Ising model under of a magnetic (h(t)) field. The influences of the amplitude (h 0) and the frequency (ω) of the h(t) magnetic field and bias field (h b) on the thermal behavior of the dynamic order parameter and the dynamic magnetocaloric properties (the dynamic isothermal Δ S iso (T , h (t)) entropy variation and the dynamic Δ T ad (T , h (t)) adiabatic variation of temperature), the dynamic specific heat, the dynamic entropy and as well as the dynamic refrigerant capacity (RC(t)) ferrimagnetic C 70 Fullerene-like structure are studied. Our results may be a reference for future experiment and theoretical studies of the nano-clusters. Highlights • The mixed spin-(3/2, 5/2) Ising C 70 Fullerene system is investigated. • The dynamic Monte Carlo simulation is used. • The dynamic heat specific is given. • The magnetic change entropy and the adiabatic temperature change are deduced. • The refrigerant capacity for a several dynamic magnetic field has been obtained. [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]

Abstract In this paper, we investigated the magnetic properties of the cubic anti-perovskite Mn 3 CuN compound by applying the Monte Carlo simulation (MCs). The magnetism in this metallic Mn 3 CuN is provided by the Mn atoms (Mn4+)having the magnetic moment S = 1 and Cu (Cu2+) atoms described by the magnetic spin momentσ = 1/2. However, we presented and discussed the ground state phase diagrams where we observed the stable phases in different planes corresponding to different physical parameters of the system at zero absolute temperature T = 0 K. On the other hand, a model describing the system is proposed to solve the Hamiltonian governing the system. The results of the physical parameters such as the susceptibilities, magnetizations and the specific heat behaviors are deduced for the finite size, as a function of temperature. Moreover, the thermal behavior of the previous physical quantities with the variation of the exchange coupling interactions, the crystal field and the external magnetic field are presented and discussed. Also, the curves of the magnetizations as a function of the crystal field are plotted. Finally, the magnetic hysteresis loops of the studied system have been drawn. Highlights • We study the Anti-perovskite Metallic compound Mn 3 CuN. • We performed Monte Carlo simulations to investigate this model. • We outlined the exchange coupling interaction effect on the compensation temperature. • The magnetic properties of such system are presented and discussed. • The hysteresis loops are obtained and presented. [ABSTRACT FROM AUTHOR]

In this work, we study the magnetic properties in a diluted ferrimagnetic materials structure, composed with three areas, by Monte Carlo simulations. The system consists of two non-equivalent types of atoms A and B, two arrangements ABA and BAB are considered. The dilution effect concerns only the B atoms. The ground state phase diagrams are reported. The effect of exchange coupling interactions on the compensation temperature is investigated. The obtained results show that the system presents a compensation temperature and different behaviors when varying the coupling parameters and the dilution probability. [ABSTRACT FROM AUTHOR]

Monte Carlo simulation has been employed to study the hysteresis behaviors of a ferrimagnetic mixed-spin (1, 3/2) Ising nanotube with hexagonal core-shell structure. The effects of different single-ion anisotropies, exchange couplings and temperature on the hysteresis loops of the system and sublattices are discussed in detail. Multiple hysteresis loops such as triple loops have been observed in the system under certain physical parameters. It is found that the anisotropy, the exchange coupling and the temperature strongly affect the coercivities and the remanences of the system and the sublattices. Comparing our results with other theoretical and experimental studies, a satisfactory agreement can be achieved qualitatively. [ABSTRACT FROM AUTHOR]

Compensation temperature T comp and transition temperature T C have significant applications for the experimental realization of magnetic nanotube structure in the field of thermal magnetic recording. In this work, we use the Monte Carlo simulation to investigate the phase diagrams, magnetizations, susceptibilities, internal energies, specific heats and hysteresis behaviors of a cylindrical ferrimagnetic nanotube with core-shell structure. The effects of the single-ion anisotropies ( D C , D S ) and the exchange couplings ( J int , J S ) on the magnetic and thermodynamic properties of the system are examined. A number of characteristic behaviors are discovered in the thermal variations, depending on different physical parameters. In particular, the triple hysteresis loops behavior has been found for appropriate physical parameters. These findings are qualitatively in good agreement with related experimental and the other theoretical results. [ABSTRACT FROM AUTHOR]

Magnetization curves of ferrimagnetic mixed spin-1 and spin-2 Heisenberg chains are calculated with the help of density-matrix renormalization group method and quantum Monte Carlo simulations by considering a spin dimerization (1,2), trimerization (1,1,2) and tetramerization (1,1,1,2). The investigated mixed-spin Heisenberg chains can be alternatively viewed as a pure spin-1 Heisenberg chain, which contains at a regular lattice positions spin-2 particles. Unlike the antiferromagnetic spin-1 Heisenberg chain solely displaying a zero magnetization plateau due to the Haldane phase, the ferrimagnetic mixed spin-(1,2), spin-(1,1,2) and spin-(1,1,1,2) Heisenberg chains exhibit more striking magnetization curves involving at least two intermediate magnetization plateaux and quantum spin-liquid states. [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]

A hexagonal nanowire consisting of a ferromagnetic spin- 1 2 core, spin-1 inter core/shell and spin- 3 2 outer shell coupled with ferrimagnetic interlayer couplings has been studied by the use of Monte Carlo simulation based on the heat bath algorithm. The exchange interactions and the uniaxial anisotropy effects on the magnetic properties of the system have been discussed. We found that, the system exhibits the compensation phenomenon, the first and the second order transitions. Moreover, we have obtained that, the existence of the tricritical point depend on the surface shell interaction. [ABSTRACT FROM AUTHOR]

Monte Carlo simulation has been used to study magnetic and thermodynamic properties of a ferrimagnetic mixed-spin (1, 3/2) Ising nanowire with hexagonal core-shell structure. The ground phase diagrams are obtained for different exchange couplings. The critical values of the exchange couplings have been found, determining whether the compensation points appear in the present system. In particular, the effects of the exchange couplings and the temperature on the magnetization, the internal energy, the specific heat, the compensation points and hysteresis loops are discussed in detail. Under certain physical parameters, multiple cycle hysteresis loops such as triple and quintuple hysteresis loop patterns have been observed in the system. It is found that the exchange coupling and the temperature strongly affect the coercivity and the remanence of the system. Compared our results with other theoretical and experimental studies, a good agreement has been obtained qualitatively. [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]

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]

In this paper, we study the magnetic properties of ferrimagnetic mixed spins with integer σ = 2 and half-integer S = 7 / 2 in a Blume–Capel model, using Monte Carlo simulations. The considered Hamiltonian includes the first nearest-neighbors and the exchange coupling interactions on the two sub-lattices. The effect of these coupling exchange interactions, in the presence of both the external magnetic field and the crystal field, are studied. The magnetizations and the corresponding susceptibilities are presented and discussed. Finally, we have interpreted the behaviors of the magnetic hysteresis of this model. [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]

• 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]

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]

In this work, a Monte Carlo simulation, based on standard Metropolis algorithm, has been applied to investigate magnetic properties of a ferrimagnetic nanoparticle, with a cubic shape and core–shell structure. The nanoparticle is constituted of spin-1/2 in the core surrounded by spin-3/2 in the shell. It has been shown that the exchange coupling plays an important role on the phase diagrams. Some interesting features have been observed for the temperature dependence of total magnetization curves of particle. In particular, the effects of the interface coupling and the shell coupling on both the compensation temperature and the magnetization profiles are investigated. In addition, the effect of the single ion anisotropy as well as the hysteresis loops behavior has also been discussed in detail. [ABSTRACT FROM AUTHOR]

• Dynamic magnetic properties of the borophene nanoribbon are studied using Monte Carlo method. • Dynamic order parameter Q versus the different physical parameters under fixed temperature are studied. • Various Q profiles and abundant saturation values are observed caused by different physical parameters. • Multi-loop hysteresis and superparamagnetic behavior are obtained under certain parameters. In this work, we applied Monte Carlo simulation to investigate the dynamic magnetic behaviors of the ferrimagnetic mixed-spin (3/2, 5/2) Ising-type borophene nanoribbons with core-shell structure. The effects of the crystal field, exchange couplings and time-dependent oscillating magnetic field on the dynamic magnetic characteristics were discussed. In addition, the hysteresis behaviors of the system were also presented and the multiple-loop hysteresis phenomena were observed. [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]

Abstract: Monte Carlo simulation based on Metropolis algorithm has been used with a great success to analyze the dynamic phase transition properties of a single spherical core–shell nanoparticle system with a spin-3/2 core surrounded by a spin-1 shell layer with antiferromagnetic interface coupling under the influence of a time dependent oscillating magnetic filed. It has been found that the dynamic phase boundaries strongly depend on the Hamiltonian parameters such as for the high amplitude and period values of the external field, the phase transition temperature sharply changes whereas it tends slowly to alter as the reduced magnitude of interlayer parameter increases. Moreover, it is observed that the magnetization curves of the particle have been found to obey P-type, N-type and Q-type classification schemes under certain conditions. Much effort has also been paid to the influence of the particle size on the thermal and magnetic properties of the particle. Finally, a comparison of our observations with those of recently published study including dynamic treatments of a nanocubic core–shell system is represented and the findings indicate that there exists a qualitatively good agreement with some relatively distinct differences. [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]

Abstract: The Monte Carlo simulation technique has been used to study the magnetic behavior of a ferrimagnetic spherical nanoparticle on a simple cubic lattice. The particle is formed by alternate layers of spins and . The interlayer coupling is antiferromagnetic. The influences of the crystal fields, and the exchange couplings, on the critical and compensation behavior of the nanoparticle, are investigated. The results present rich critical behavior, which includes the first- and second-order phase transitions, thus also the tricritical and critical end points. It is also found that the compensation point can appear for appropriate values of the system parameters. [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]