Method Of Fourth-order Binder Cumulants Research Articles

Fazovye perekhody v chasovoy modeli s chislom sostoyaniy spina <i>q </i>= 5 na treugol'noy reshetke

The phase transitions and thermodynamic properties of the clock model with q = 5 spin states on a triangular lattice have been investigated using the Wang–Landau Monte Carlo algorithm. The phase transitions have been analyzed with the histogram method and the fourth-order Binder cumulant method. Two Berezinskii–Kosterlitz–Thouless phase transitions are shown to be observed in the ferromagnetic clock model, while a second-order phase transition has been detected in the antiferromagnetic clock model.

Phase Transitions and the Thermodynamic Properties of the Potts Model with the Spin State Number q = 4 at a Kagome Lattice

Phase transitions and the thermodynamic properties of the two-dimensional ferromagnetic Izing model with spin state number q = 4 on a kagome lattice are studied by the Monte Carlo method on the base of the Wang–Landau algorithm. The phase transition character is analyzed using the fourth-order Binder cumulant method and the histogram analysis of the data. It is found that this model undergoes a first-order phase transition.

Effect of quenched non-magnetic impurities on phase transitions in a two-dimensional Potts model

The Wolff cluster Monte Carlo algorithm is used to investigate the effect of frozen nonmagnetic canonically distributed impurities on the phase transitions in a two-dimensional Potts model with the spin state q = 5. Systems with linear dimensions L = 20–160 at spin concentrations p = 1.0 and 0.9 are considered. Using the fourth-order Binder cumulant method and the histogram analysis method it is shown that if a weak quenched disorder in the form of non-magnetic impurities (p = 0.9) is introduced in the system, the first-order phase transition changes to a second-order phase transition.

Influence of Quenched Non-Magnetic Impurities on Phase Transitions in Low-Dimensional Potts Models

The effect of quenched non-magnetic impurities on phase transitions in low-dimensional Potts model structures is investigated by the Monte Carlo method using a cluster algorithm. Systems with linear dimensions of L = 20–160 and spin concentrations of p = 1.0, 0.9 are considered. Using the fourth-order Binder cumulant method and the histogram-data analysis method, the introduction of weak quenched disorder (p = 0.9) in the form of non-magnetic impurities is shown to change the order of the phase transition from the first to the second.

Phase Transformations and Thermodynamic Properties of the Potts Model with q = 4 on a Hexagonal Lattice with Interactions of Next-Nearest Neighbors

The magnetic structures of the ground state, phase transitions, and the thermodynamic properties of a two-dimensional ferromagnetic Potts model with the number of spin states q = 4 on a hexagonal lattice are studied using the Wang–Landau algorithm of the Monte Carlo method, taking into account the interactions of the nearest and the next-nearest neighbors. It is shown that the inclusion of the antiferromagnetic interactions of the next-nearest neighbors leads to the appearance of frustration and disturbance of magnetic ordering. The phase transition characters are analyzed using the method of fourth-order Binder cumulants and the histogram method. It is found that a first-order phase transition takes place in this model.

Phase transitions in the Ising model on a triangular lattice with different values of interlayer exchange interaction

The Monte Carlo method was used to study the phase transitions and thermodynamic properties of the three-dimensional antiferromagnetic Ising model on a layered triangular lattice at various values of interlayer exchange interaction. A number of investigations have been carried out for the ratios of the intralayer (J1) and interlayer (J2) exchange interactions within the range of r = J2/J1 = 0.01–1.0. The nature of the phase transitions was studied using the fourth-order Binder cumulant method and histogram data analysis. It has been shown that in the considered range r, the transition from a disordered phase to an ordered phase is a second-order phase transition.

Phase transitions in the two-dimensional four-vertex Potts model with quenched nonmagnetic impurities

The thermodynamic properties and phase transitions in the two-dimensional weakly diluted Potts model with the number of spin states q=4 were studied by the Monte Carlo method. Systems with linear dimensions L×L = N, L=10–160 are considered. Using the fourth order Binder cumulant method, critical temperatures were calculated for spin systems with a spin concentration p=1.0 and 0.90. Critical indices are calculated on the basis of the theory of finite-size scaling. The universality of the critical behavior of two-dimensional disordered systems is discussed.

Influence of quenched non-magnetic impurities on phase transitions in the two-dimensional Potts model with q = 5

Abstract Thermodynamic properties and phase transitions in 2d weakly diluted Potts model on a square lattice are investigated by the Monte Carlo method. We consider the systems with linear sizes L × L = N, L = 10–160. Using the fourth order Binder cumulant method, it was shown that the introduction of non-magnetic impurities into the spin system described by the two-dimensional Potts model with q = 5 leads to a change in the first-order phase transition to the second-order phase transition.

Critical Temperature of the Three-Vertex Potts Model on a Kagome Lattice

The Potts model on a Kagome lattice is considered. The Monte Carlo method is used to obtain the temperature dependences of the thermodynamic parameters: heat capacity C, order parameter m, and susceptibility χ. The calculations were performed for systems with periodic boundary conditions. Systems with linear dimensions L × L = N, L = 20–90, were considered. Based on the fourth-order Binder cumulant method, the critical temperature (Tc) was calculated for the three-vertex Potts model on a Kagome lattice. It is shown that the obtained value of Tc, within the statistical error, is in good agreement with the results obtained by the transfer matrix and polynomial approximation methods.

Критическая температура трехвершинной модели Поттса на решетке Кагоме

The Potts model on the Kagome lattice is considered. The Monte Carlo method is used to obtain the temperature dependences of the thermodynamic parameters of heat capacity C, order parameter m, and susceptibility χ. The calculations were performed for systems with periodic boundary conditions. Systems with linear dimensions LxL = N, L = 20-90 were considered. Based on the fourth order Binder cumulant method, the critical temperature (Tc) was calculated for the three-vertex Potts model on the Kagome lattice. It is shown that the obtained Tc value within the statistical error is in good agreement with the results obtained using the transfer-matrix and polynomial approximation methods.

Phase transitions and thermodynamic properties of the antiferromagnetic Potts model on a face-centered cubic lattice

Using the Monte Carlo method we investigate the phase transitions and thermodynamic properties of magnetic structures with noncollinear directions of magnetic moments corresponded to antiferromagnetic q=4 Potts model on a face-centered cubic lattice. Monte Carlo simulations are performed on lattices with linear sizes L=20÷44. Thermodynamic parameters: the order parameter mAF, susceptibility χ, internal energy U, and specific heat C are evaluated for all studied systems. By employing the fourth order Binder cumulant method, a first order transition is shown to be occurred in the model.

Investigation of the thermodynamic properties and phase transitions in a strongly diluted three-vertex antiferromagnetic Potts model by the Monte Carlo method

The thermodynamic properties and phase transitions in a two-dimensional strongly diluted threevertex antiferromagnetic Potts model on a triangular lattice have been investigated using the Monte Carlo method. The systems with linear dimensions of L × L = N, where L = 18–48, have been considered. It has been shown using the method of fourth-order Binder cumulants that, upon the introduction of nonmagnetic impurities into the spin system described by the two-dimensional antiferromagnetic Potts model, the firstorder phase transition changes to a second-order phase transition.

Influence of Quenched Nonmagnetic Impurities on Phase Transitions in Two-Dimensional 3-State Antiferromagnetic Potts Model on Triangular Lattice

An influence of quenched nonmagnetic disorder on the phase transitions in the two dimensional antiferromagnetic Potts model with a number of spin state q=3 on a triangular lattice is calculated by the Monte-Carlo method. The systems with linear sizes L=20÷144 at spin concentrations p=1.00, 0.90, 0.80 are studied. By means of the fourth order Binder cumulant method, the inclusion of a quenched disorder as nonmagnetic impurities into a pure antiferromagnetic Potts model is shown to be the cause of the change of the first order phase transition into the second one.

Effect of quenched-in nonmagnetic impurities on phase transitions in a two-dimensional antiferromagnetic three-vertex Potts model on a triangular lattice

The effect of quenched-in nonmagnetic impurities on phase transitions in a two-dimensional diluted antiferromagnetic three-vertex Potts model on a triangular lattice has been investigated using the Monte Carlo method. The systems with linear dimensions L × L = N and L = 9–144 have been considered. It has been shown using the fourth-order Binder cumulant method that the introduction of a quenched-in disorder into a spin system described by the two-dimensional antiferromagnetic Potts model leads to a change from the first-order phase transition to the second-order phase transition.

Phase transitions in the two-dimensional ferro- and antiferromagnetic potts models on a triangular lattice

The phase transitions in the two-dimensional ferro- and antiferromagnetic Potts models with q = 3 states of spin on a triangular lattice are studied using cluster algorithms and the classical Monte Carlo method. Systems with linear sizes L = 20–120 are considered. The method of fourth-order Binder cumulants and histogram analysis are used to discover that a second-order phase transition occurs in the ferromagnetic Potts model and a first-order phase transition takes place in the antiferromagnetic Potts model. The static critical indices of heat capacity (α), magnetic susceptibility (γ), magnetization (β), and correlation radius index (ν) are calculated for the ferromagnetic Potts model using the finite-size scaling theory.

Influence of quenched nonmagnetic impurities on phase transitions in a three-dimensional diluted Potts model with spin state number q = 4

The influence of quenched nonmagnetic impurities on phase transitions and critical phenomena in the 3D Potts model with the spin state number q = 4 is studied using the Monte Carlo method. Systems with the linear size L = 20–32 and spin concentrations p = 1.00, 0.90, 0.65 are considered. The fourth order Binder cumulant method is used to demonstrate that in the strongly diluted regime, a phase transition of the second kind is observed in this model for the spin concentration p = 0.65, and a phase transition of the first kind is observed for the pure (p = 1.00) and weakly diluted (p = 0.90) models. The theory of finite-dimensional scaling is used to calculate the static critical parameters of heat capacity α, susceptibility γ, magnetization β, and correlation radius ν.

Phase transitions in a three-dimensional diluted Potts model with 4 spin states

A Monte–Carlo method is used to study phase transitions and critical phenomena in a three-dimensional Potts model with 4 spin states and nonmagnetic impurities. Systems with linear sizes L=20–32 and spin concentrations p=1.00, 0.90, and 0.65 are studied. A fourth order Binder cumulant method is used to show that this model yields a second order phase transition for strong dilution with a spin concentration p=0.65, while the pure model (p=1.00) and the model with weak dilution (p=0.90) yield a first order phase transition. The static critical indices for the heat capacity α, susceptibility γ, magnetization β, and correlation radius ν are calculated using a finite-dimensional scaling theory.

Monte Carlo investigation of phase transitions in the frustrated Heisenberg model on a triangular lattice

The critical properties and phase transitions of the three-dimensional frustrated antiferromagnetic Heisenberg model on a triangular lattice have been investigated using the Monte Carlo method with a replica algorithm. The critical temperature has been determined and the character of the phase transitions has been analyzed using the method of fourth-order Binder cumulants. A second-order phase transition has been found in the three-dimensional frustrated Heisenberg model on a triangular lattice. The static magnetic and chiral critical exponents of the heat capacity α, the susceptibility γ and γk, the magnetization β and βk, the correlation length ν and νk, as well as the Fisher exponents η and ηk, have been calculated in terms of the finite-size scaling theory. It has been demonstrated that the three-dimensional frustrated antiferromagnetic Heisenberg model on a triangular lattice forms a new universality class of the critical behavior.

Features of the phase transitions in the three-dimensional diluted potts model with number of spin states q = 3

The effect of frozen disorder, implemented in the form of nonmagnetic impurities, on phase transitions in the three-dimensional Potts model with number of states q = 3 has was investigated by the Monte Carlo method, using the Wolf single-cluster algorithm. Systems with linear sizes L = 20–44 were considered at spin concentrations p = 1.00–0.65. The method of fourth-order Binder cumulants was used to demonstrate that a first-order phase transition is observed for the pure model (p = 1.00) and a second-order phase transition occurs at concentrations p = 0.90, 0.80, 0.70, and 0.65.

Investigation of the Critical Properties in the 3D Site-Diluted Potts Model

The effect of quenched nonmagnetic impurities on phase transitions in the three-dimensional Potts model with the number of spin states q=3 is studied using the Wolff single-cluster algorithm of the Monte Carlo method. By the method of fourth-order Binder cumulants, it is demonstrated that the second-order phase transition occurs in the model under study at spin concentrations p=0.9, 0.8, 0.7, and 0.65, while the first-order phase transition is observed in the pure model (p=1.0). The static critical exponents (CEs) α (heat capacity), γ (susceptibility), β (magnetization), and ν (correlation length) are calculated based on the finite-size scaling theory.