We study the entanglement in anisotropie (1/2,1) mixed-spin Heisenberg XY model under the presence of an external magnetic field at thermal equilibrium. By adjusting the anisotropic parameter and the magnetic field,...We study the entanglement in anisotropie (1/2,1) mixed-spin Heisenberg XY model under the presence of an external magnetic field at thermal equilibrium. By adjusting the anisotropic parameter and the magnetic field, one is able to obtain entanglement at higher temperature. We find the evidence of the quantum phase transition in the model and observe that the quantum phase transition point at low temperature moves toward weak magnetic field with the increase of the anisotropic parameter.展开更多
The magnetic properties of a mixed Ising ferrimagnetic system consisting of spin-3/2 and spin-2 with different single ion anisotropies and under the effect of an applied longitudinal magnetic field are investigated wi...The magnetic properties of a mixed Ising ferrimagnetic system consisting of spin-3/2 and spin-2 with different single ion anisotropies and under the effect of an applied longitudinal magnetic field are investigated within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. The ground-state phase diagram is constructed. The thermal behaviours of magnetizations and magnetic susceptibilities are examined in detail. Finally, we find some interesting phenomena in these quantities, due to applied longitudinal magnetic field.展开更多
In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correla...In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correlationfunctions are obtained by using the Tyablikov decoupling approximation.Our results show that the magnetic susceptibilityand correlation length are a monotonically decreasing function of temperature regardless of the mixed spins.It isfound that in the case of S = s, our results of one-dimensional mixed-spin model is reduced to be those of the isotropicferromagnetic Heisenberg chain in the whole temperature region.Our results for the susceptibility are in agreement withthose obtained by other theoretical approaches.展开更多
Influences of crystal-fields (DA and DB ) and interlayer coupling interactions (J3) on dynamic magnetic critical behaviors of a mixed-spin (3//2, 2) bilayer system under an oscillating magnetic field are investi...Influences of crystal-fields (DA and DB ) and interlayer coupling interactions (J3) on dynamic magnetic critical behaviors of a mixed-spin (3//2, 2) bilayer system under an oscillating magnetic field are investigated by the Glauber-type stochastic dynamics based on the mean-field theory. For this purpose, dynamic phase diagrams are constructed in the reduced temperature and magnetic field amplitude plane for the ferromagnetic/ferromagnetic (FM/FM), antiferromagnetic/ferromagnetic (AFM/FM) and AFM/AFM interactions in detail. We observe that the influences of DA, DB and Ja interactions parameters on the behavior of the dynamic phase diagrams are very much.展开更多
We study the local quantum Fisher information(LQFI)in the mixed-spin Heisenberg XXZ chain.Both the maximal and minimal LQFI are studied and the former is essential to determine the accuracy of the quantum parameter es...We study the local quantum Fisher information(LQFI)in the mixed-spin Heisenberg XXZ chain.Both the maximal and minimal LQFI are studied and the former is essential to determine the accuracy of the quantum parameter estimation,the latter can be well used to characterize the discord-type quantum correlations.We investigate the effects of the temperature and the anisotropy parameter on the maximal LQFI and thus on the accuracy of the parameter estimation.Then we make use of the minimal LQFI to study the discord-type correlations of different site pairs.Different dimensions of the subsystems cause different values of the minimal LQFI which reflects the asymmetry of the discord-type correlation.In addition,the site pairs at different positions of the spin chains have different minimal LQFI,which reveals the influence of the surrounding spins on the bipartite quantum correlation.Our results show that the LQFI obtained through a simple calculation process provides a convenient way to investigate the discord-type correlation in high-dimensional systems.展开更多
The thermal entanglement in (1/2,1) mixed-spin Heisenberg XXZ model is investigated under an external nonuniform magnetic field. In the uniform magnetic field system,the critical magnetic field Bc and critical tempera...The thermal entanglement in (1/2,1) mixed-spin Heisenberg XXZ model is investigated under an external nonuniform magnetic field. In the uniform magnetic field system,the critical magnetic field Bc and critical temperature Tc are increased by increasing the anisotropic parameter k. The degree of magnetic field b plays an important role in improving the critical temperature and enlarging the region of entan-glement in the nonuniform magnetic field system.展开更多
The effect of Dzialoshinski-Moriya (DM) interaction on thermal entanglement of a mixed-spin chain in an external magnetic field is investigated. It is found that DM interaction may enhance quantum thermal entanglement...The effect of Dzialoshinski-Moriya (DM) interaction on thermal entanglement of a mixed-spin chain in an external magnetic field is investigated. It is found that DM interaction may enhance quantum thermal entanglement to a maximal value even though the magnetic field plays a positive role in shrinking thermal entanglement in the mixed-spin chain. Furthermore, the effect of inhomogeneity of the magnetic field on quantum entanglement is analyzed. Our analysis will shed some light on the understanding of the effect of the DM interaction on thermal entanglement of a mixed-spin chain.展开更多
By using the concept of negativity, we investigate the thermal entanglement of a two-spin (1/2, 3/2) mixed-spin Heisenberg XX chain with an inhomogeneous external magnetic field. We obtain the analytical results of en...By using the concept of negativity, we investigate the thermal entanglement of a two-spin (1/2, 3/2) mixed-spin Heisenberg XX chain with an inhomogeneous external magnetic field. We obtain the analytical results of entanglement of this model. For the case of uniform magnetic field, we find that the critical temperature is higher than the results of the spin-1/2 chain and (1/2,1) mixed-spin chain. And by adjusting the nonuniform parameter b, one is able to obtain more entanglement at a higher temperature.展开更多
This work focuses on the ground-state phase diagram,the compensation temperatures and the critical behaviors of a ferrimagnetic graphene-like trilayer induced by crystal fields and exchange couplings.The simulation re...This work focuses on the ground-state phase diagram,the compensation temperatures and the critical behaviors of a ferrimagnetic graphene-like trilayer induced by crystal fields and exchange couplings.The simulation results show that a negative decrease in crystal field or an increase in exchange coupling can increase the critical temperature.More importantly,an M curve with double compensation temperatures can be observed,which is not predicted by the Neel theory.This remarkable compensation phenomenon has potential application value in the field of magnetic recording.展开更多
The mixed spin-3/2 and spin-2 Ising ferrimagnetic system with different single-ion anisotropies in the absence of an external magnetic field is studied within the mean-field theory based on Bogoliubov inequality for t...The mixed spin-3/2 and spin-2 Ising ferrimagnetic system with different single-ion anisotropies in the absence of an external magnetic field is studied within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. Second-order critical lines are obtained in the temperature-anisotropy plane. Tricritical line separating second-order and first-order lines is found. Finally, the existence and dependence of a compensation points on single-ion anisotropies is also investigated for the system. As a result, this mixed-spin model exhibits one, two or three compensation temperature depending on the values of the anisotropies.展开更多
基金supported by National Natural Science Foundation of China under Grant No.10674181
文摘We study the entanglement in anisotropie (1/2,1) mixed-spin Heisenberg XY model under the presence of an external magnetic field at thermal equilibrium. By adjusting the anisotropic parameter and the magnetic field, one is able to obtain entanglement at higher temperature. We find the evidence of the quantum phase transition in the model and observe that the quantum phase transition point at low temperature moves toward weak magnetic field with the increase of the anisotropic parameter.
文摘The magnetic properties of a mixed Ising ferrimagnetic system consisting of spin-3/2 and spin-2 with different single ion anisotropies and under the effect of an applied longitudinal magnetic field are investigated within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. The ground-state phase diagram is constructed. The thermal behaviours of magnetizations and magnetic susceptibilities are examined in detail. Finally, we find some interesting phenomena in these quantities, due to applied longitudinal magnetic field.
基金Supported by the Natural Science Foundation of Guangdong Province under Grant No.8151009001000055
文摘In this paper, we apply the two-time Green's function method, and provide a simple way to study themagnetic properties of one-dimensional spin-(S, s) Heisenberg ferromagnets.The magnetic susceptibility and correlationfunctions are obtained by using the Tyablikov decoupling approximation.Our results show that the magnetic susceptibilityand correlation length are a monotonically decreasing function of temperature regardless of the mixed spins.It isfound that in the case of S = s, our results of one-dimensional mixed-spin model is reduced to be those of the isotropicferromagnetic Heisenberg chain in the whole temperature region.Our results for the susceptibility are in agreement withthose obtained by other theoretical approaches.
基金Supported by Erciyes University Research Fund under Grant No.FBA-2016-6324
文摘Influences of crystal-fields (DA and DB ) and interlayer coupling interactions (J3) on dynamic magnetic critical behaviors of a mixed-spin (3//2, 2) bilayer system under an oscillating magnetic field are investigated by the Glauber-type stochastic dynamics based on the mean-field theory. For this purpose, dynamic phase diagrams are constructed in the reduced temperature and magnetic field amplitude plane for the ferromagnetic/ferromagnetic (FM/FM), antiferromagnetic/ferromagnetic (AFM/FM) and AFM/AFM interactions in detail. We observe that the influences of DA, DB and Ja interactions parameters on the behavior of the dynamic phase diagrams are very much.
基金supported by the National Natural Science Foundation of China(NSFC)under Grant No.12175052the Postdoctoral Science Foundation of China(No.2022M722794).
文摘We study the local quantum Fisher information(LQFI)in the mixed-spin Heisenberg XXZ chain.Both the maximal and minimal LQFI are studied and the former is essential to determine the accuracy of the quantum parameter estimation,the latter can be well used to characterize the discord-type quantum correlations.We investigate the effects of the temperature and the anisotropy parameter on the maximal LQFI and thus on the accuracy of the parameter estimation.Then we make use of the minimal LQFI to study the discord-type correlations of different site pairs.Different dimensions of the subsystems cause different values of the minimal LQFI which reflects the asymmetry of the discord-type correlation.In addition,the site pairs at different positions of the spin chains have different minimal LQFI,which reveals the influence of the surrounding spins on the bipartite quantum correlation.Our results show that the LQFI obtained through a simple calculation process provides a convenient way to investigate the discord-type correlation in high-dimensional systems.
基金Supported by the National Natural Science Foundation of China (Grant No. 60607013)
文摘The thermal entanglement in (1/2,1) mixed-spin Heisenberg XXZ model is investigated under an external nonuniform magnetic field. In the uniform magnetic field system,the critical magnetic field Bc and critical temperature Tc are increased by increasing the anisotropic parameter k. The degree of magnetic field b plays an important role in improving the critical temperature and enlarging the region of entan-glement in the nonuniform magnetic field system.
基金the National Natural Science Foundation of China (Grant No. 60573008)Anhui Foundation for Young Teachers (Grant No. 2008jq1025zd)
文摘The effect of Dzialoshinski-Moriya (DM) interaction on thermal entanglement of a mixed-spin chain in an external magnetic field is investigated. It is found that DM interaction may enhance quantum thermal entanglement to a maximal value even though the magnetic field plays a positive role in shrinking thermal entanglement in the mixed-spin chain. Furthermore, the effect of inhomogeneity of the magnetic field on quantum entanglement is analyzed. Our analysis will shed some light on the understanding of the effect of the DM interaction on thermal entanglement of a mixed-spin chain.
文摘By using the concept of negativity, we investigate the thermal entanglement of a two-spin (1/2, 3/2) mixed-spin Heisenberg XX chain with an inhomogeneous external magnetic field. We obtain the analytical results of entanglement of this model. For the case of uniform magnetic field, we find that the critical temperature is higher than the results of the spin-1/2 chain and (1/2,1) mixed-spin chain. And by adjusting the nonuniform parameter b, one is able to obtain more entanglement at a higher temperature.
基金funded by National Natural Science Foundation of China(grant no.U22A20215)the Natural Science Foundation of Liaoning Province(grant no.2023MS-218)
文摘This work focuses on the ground-state phase diagram,the compensation temperatures and the critical behaviors of a ferrimagnetic graphene-like trilayer induced by crystal fields and exchange couplings.The simulation results show that a negative decrease in crystal field or an increase in exchange coupling can increase the critical temperature.More importantly,an M curve with double compensation temperatures can be observed,which is not predicted by the Neel theory.This remarkable compensation phenomenon has potential application value in the field of magnetic recording.
文摘The mixed spin-3/2 and spin-2 Ising ferrimagnetic system with different single-ion anisotropies in the absence of an external magnetic field is studied within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. Second-order critical lines are obtained in the temperature-anisotropy plane. Tricritical line separating second-order and first-order lines is found. Finally, the existence and dependence of a compensation points on single-ion anisotropies is also investigated for the system. As a result, this mixed-spin model exhibits one, two or three compensation temperature depending on the values of the anisotropies.