Phase Transitions

Dynamic magnetic properties of spin-7/2 multilayer Ising system in an oscillating magnetic field

Mehmet Ertaş, Mehmet Batı

Published Feb 21, 2023• 9 citations

Abstract

We studied the dynamic magnetic properties such as dynamic phase transitions, dynamic compensation temperatures, and dynamic phase diagrams in the spin-7/2 multilayer Ising system under an oscillating external magnetic field The system was simulated in the mean-field approximation using a Glauber type stochastic dynamic. The mean sublattice magnetizations’ time variations were examined to determine the system's dynamic phases. The thermal behavior of dynamic sublattice magnetizations was investigated to determine the type of dynamic phase transitions (first- or second-order) and to obtain the dynamic compensation temperatures. P−,Q−,R−,S−, and L−type compensating behaviors were seen in various types of magnetization curves. The phase diagrams are calculated in J−T, T−h, and d−T planes, for different values of the Hamiltonian parameters. The p, i, f1/2, f7/2, af7/2, and af1/2 fundamental phases, as well as the i + p, i + f1/2, af1/2 + p, af7/2 + p and i + af1/2 mixed phases. The system illustrated one, two, or three dynamic critical points (•) and E, TP, Z, and B special points.

DOI: 10.1080/01411594.2023.2177161

Related papers

The dynamic compensation temperature in a kinetic spin-5/2 Ising model on a hexagonal lattice

Ümüt Temizer, Ayşegül Özkılıç

We present a study of the dynamic behavior of a two-sublattice spin-5/2 Ising model with bilinear and crystal-field interactions in the presence of a time-dependent oscillating external magnetic field on alternating layers of a hexagonal lattice by using the Glauber-type stochastic dynamics. The lattice is formed by alternate layers of spins σ = 5/2 and S = 5/2. We employ the Glauber transition rates to construct the mean-field dynamic equations. First, we investigate the time variations of the average sublattice magnetizations to find the phases in the system and then the thermal behavior of the dynamic sublattice magnetizations to characterize the nature (first- or second-order) of the phase transitions and to obtain the dynamic phase transition (DPT) points. We also study the thermal behavior of the dynamic total magnetization to find the dynamic compensation temperature and to determine the type of the dynamic compensation behavior. We present the dynamic phase diagrams, including the dynamic compensation temperatures, in nine different planes. The phase diagrams contain seven different fundamental phases, thirteen different mixed phases, in which the binary and ternary combination of fundamental phases and the compensation temperature or the L -type behavior strongly depend on the interaction parameters.

Chinese Physics BMar 1, 20137 citations

Dynamic critical behavior of the mixed-spin (1, 3/2, 2) trilayer Ising system

Muhammed Derviş Baran, Ümüt Temizer

The dynamic magnetic behavior of the mixed-spin Ising trilayer structure, composed of a ferrimagnetically A-layer with spin-1, B-layer with spin-3/2 and a C-layer with spin-2, is investigated by using the mean-field approximation with Glauber-type stochastic dynamics. The dynamic equations describing the time-dependencies of the system are derived from the Master equation and the Glauber transition rates. The time variations of the average magnetizations and the behaviors of the dynamic magnetizations as a function of the temperature and magnetic field are investigated to find the phases and phase transition points, respectively. The dynamic phase diagrams are presented on different planes, and they exhibit several ordered phases and coexistence phase regions besides the disordered phase. Our model highlights first- and second-order phase transitions as well as the emergence of tricritical point, triple point, quadruple point, critical end point, double critical end point and multicritical point.

Phase TransitionsApr 3, 20260 citations

Dynamic phase transitions in the kinetic mixed spin-1/2 and spin-5/2 Ising model under a time-dependent oscillating magnetic field

Bayram Deviren, Mustafa Keskín, Osman Canko

We calculate the dynamic phase transition (DPT) temperatures and present the dynamic phase diagrams in the kinetic mixed spin-1/2 and spin-5/2 Ising model under the presence of a time-dependent oscillating external magnetic field. We employ the Glauber transition rates to construct the set of mean-field dynamic equations. The time variation of the average magnetizations and the thermal behavior of the dynamic magnetizations are investigated, extensively. The nature (continuous or discontinuous) of the transitions is characterized by studying the thermal behaviors of the dynamic magnetizations. The DPT points are obtained and the phase diagrams are presented in two different planes. Phase diagrams contain four fundamental phases and three coexistence or mixed phases, which strongly depend on interaction parameters. The phase diagrams are discussed and a comparison is made with the results of the other mixed spin Ising systems.

Phase TransitionsJul 1, 20107 citations

Dynamic phase transition in the kinetic spin-5/2 Blume–Emery–Griffiths model in an oscillating external magnetic field

Mustafa Keskín, Mehmet Ertaş

Employing a mean-field approach, we study the stationary states of the kinetic spin-5/2 Blume–Emery–Griffiths (BEG) model under the presence of a time-varying (sinusoidal) magnetic field by using the Glauber-type stochastic dynamics. We employ the Glauber transition rates to construct the set of dynamic mean-field equations. We investigate the time variation in average order parameters to find the phases in the system, and the thermal behavior of the dynamic order parameters to characterize the nature (continuous or discontinuous) of the dynamic phase transtions and to the dynamic phase transition temperature. The dynamic phase diagrams are presented in three different planes. The phase diagrams contain the ferromagnetic-5/2, the ferromagnetic-3/2, the ferromagnetic-1/2, the ferroquadrupolar, and disordered fundamental phases. They also include the nine coexisting or mixed phases composed of binary and ternary combinations of fundamental phases that strongly depend on the interaction parameters. The phase diagrams display the critical end point, double critical end point, triple point, quadruple point, and one, two, or three special points and the dynamic tricritical point that depends on the interaction parameters.

Phase TransitionsMay 1, 201010 citations

Nonequilibrium behavior of the kinetic metamagnetic spin-5/2 Blume—Capel model

Ümüt Temizer

The dynamic magnetic behavior of the kinetic metamagnetic spin-5/2 Blume—Capel model is examined, within a mean-field approach, under a time-dependent oscillating magnetic field. To describe the kinetics of the system, Glauber-type stochastic dynamics has been utilized. The mean-field dynamic equations of the model are obtained from the Master equation. Firstly, these dynamic equations are solved to find the phases in the system. Then, the dynamic phase transition temperatures are obtained by investigating the thermal behavior of dynamic sublattice magnetizations. Moreover, from this investigation, the nature of the phase transitions (first- or second-order) is characterized. Finally, the dynamic phase diagrams are plotted in five different planes. It is found that the dynamic phase diagrams contain the paramagnetic (P), antiferromagnetic (AF 5/2 , AF 3/2 , AF 1/2 ) phases and five different mixed phases. The phase diagrams also display many dynamic critical points, such as tricritical point, triple point, quadruple point, double critical end point and separating point.

Chinese Physics BJul 1, 20146 citations

Nonequilibrium magnetic properties in a two-dimensional kinetic mixed Ising system within the effective-field theory and Glauber-type stochastic dynamics approach

Mehmet Ertaş, Bayram Deviren, Mustafa Keskín

Nonequilibrium magnetic properties in a two-dimensional kinetic mixed spin-2 and spin-5/2 Ising system in the presence of a time-varying (sinusoidal) magnetic field are studied within the effective-field theory (EFT) with correlations. The time evolution of the system is described by using Glauber-type stochastic dynamics. The dynamic EFT equations are derived by employing the Glauber transition rates for two interpenetrating square lattices. We investigate the time dependence of the magnetizations for different interaction parameter values in order to find the phases in the system. We also study the thermal behavior of the dynamic magnetizations, the hysteresis loop area, and dynamic correlation. The dynamic phase diagrams are presented in the reduced magnetic field amplitude and reduced temperature plane and we observe that the system exhibits dynamic tricritical and reentrant behaviors. Moreover, the system also displays a double critical end point (B), a zero-temperature critical point (Z), a critical end point (E), and a triple point (TP). We also performed a comparison with the mean-field prediction in order to point out the effects of correlations and found that some of the dynamic first-order phase lines, which are artifacts of the mean-field approach, disappeared.

Physical Review ENov 7, 201257 citations