We investigate the properties of thermal quantum correlations in an infinite spin-1/2 Ising-Heisenberg diamond chain with Dzyaloshinskii-Moriya（DM） interaction. The thermal quantum discord（TQD） and the thermal ent...We investigate the properties of thermal quantum correlations in an infinite spin-1/2 Ising-Heisenberg diamond chain with Dzyaloshinskii-Moriya（DM） interaction. The thermal quantum discord（TQD） and the thermal entanglement（TE）are discussed as two kinds of important methods to measure the quantum correlation, respectively. It is found that DM interaction plays an important role in the thermal quantum correlations of the system. It can enhance the thermal quantum correlations by increasing DM interaction. Furthermore, the thermal quantum correlations can be promoted by tuning the external magnetic field and the Heisenberg coupling parameter in the antiferromagnetic system. It is shown that the behaviors of TQD differ from those of TE. TQD is more robust against decoherence than TE. For the measurement of TQD, the ＂regrowth＂ phenomenon occurs in the ferromagnetic system. We also find that the anisotropy favors the thermal quantum correlations of the system with weak DM interaction.展开更多
We investigate the thermal entanglement of the spin-1 Ising-Heisenberg diamond chain, which can be regarded as a theoretical model for the homometallic molecular ferrimagnet [Ni_3（C_4H_2O_4）_2-（μ_3-OH）_2（H_2O）_...We investigate the thermal entanglement of the spin-1 Ising-Heisenberg diamond chain, which can be regarded as a theoretical model for the homometallic molecular ferrimagnet [Ni_3（C_4H_2O_4）_2-（μ_3-OH）_2（H_2O）_4]n ·（2H_2O）n. Two cases,i.e., the isotropic Heisenberg（Ising-XXX） coupling model and anisotropic Heisenberg（Ising-XXZ） coupling model, are discussed respectively. The negativity is chosen as the measurement of the thermal entanglement. By means of the transfermatrix approach, we focus on the effects of biquadratic interaction parameters on the negativity of the infinite spin-1 Ising-Heisenberg diamond chain. In the Ising-XXX coupling model, it is shown that for the case with ferromagnetic coupling the thermal entanglement can be induced by the biquadratic interaction, but the external magnetic field will suppress the occurrence of the entanglement induced by the biquadratic interaction. In the Ising-XXZ coupling model,for the case with antiferromagnetic coupling, due to the biquadratic interaction the effect of the anisotropy parameter on the entanglement will be suppressed at near-zero temperature. Moreover, the biquadratic interaction makes the threshold temperature increase. The effects of the external magnetic field on the thermal entanglement are also discussed, and it is observed that the entanglement revival phenomena exist in both models considered.展开更多
We investigate the thermal entanglement in a spin-l/2 Ising-Heisenberg diamond chain, in which the vertical Heisen- berg spin dimers alternate with single Ising spins. Due to the fact that the Dzyaloshinskii-Moriya ...We investigate the thermal entanglement in a spin-l/2 Ising-Heisenberg diamond chain, in which the vertical Heisen- berg spin dimers alternate with single Ising spins. Due to the fact that the Dzyaloshinskii-Moriya （DM） interaction con- tributes to unusual and interesting magnetic properties in actual materials, and moreover it plays a significant role in the degree of the entanglement of the Heisenberg quantum spin systems, we focus on the effects of different DM interactions, including Dz and Dx, on the thermal entanglement of the Heisenberg spin dimer. The concurrence, as a measure of spin dimer entanglement, is calculated for different values of exchange interactions, DM interaction, external magnetic field, and temperature. It is found that the critical temperature and the critical magnetic field corresponding to the vanishing of entanglement increase with DM interaction, and the entanglement revival region gets larger by increasing DM interac- tion, thus DM interaction favors the formation of the thermal entanglement. It is observed that different DM interaction parameters （Dz and Dx） have remarkably different influences on the entanglement. Different from the case Dz, there is the non-monotonic variation of the concurrence with temperature in the case Dx, and additionally the DM interaction Dx can induce the entanglement near zero temperature in the case that the antiferromagnetic Ising-type interaction constant is larger than the antiferromagnetic Heisenberg interaction constant. It is also shown that for the same value of DM interaction the critical magnetic field of the case Dx is larger than that of the case Dz.展开更多
The magnetic properties of a mixed spin-2 and spin-1/2 ferromagnetic diamond chain are studied by effective-field theory and Monte Carlo（MC） simulation based on the Ising model.The temperature dependences of magneti...The magnetic properties of a mixed spin-2 and spin-1/2 ferromagnetic diamond chain are studied by effective-field theory and Monte Carlo（MC） simulation based on the Ising model.The temperature dependences of magnetization,magnetic susceptibility,internal energy,and specific heat are studied,respectively.The exchange interaction dependences of magnetization and the critical temperature are calculated by MC simulation.The changes of magnetization depending on the field increasing and then the field decreasing under steady-static conditions are also given.展开更多
We consider an entangled Ising-XY Z diamond chain structure. Quantum correlations for this model are inves- tigated by using quantum discord and trace distance discord. Quantum correlations are obtained for different ...We consider an entangled Ising-XY Z diamond chain structure. Quantum correlations for this model are inves- tigated by using quantum discord and trace distance discord. Quantum correlations are obtained for different values of the anisotropy parameter, magnetic field and temperature. By comparison between quantum correlations, we show that the trace distance discord is always larger than quantum discord. Finally, some novel effects such as increasing the quantum correlations with temperature and constructive role of anisotropy parameter, which may play to the quantum correlations, are observed.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11274102)the New Century Excellent Talents in University of Ministry of Education of China(Grant No.NCET-11-0960)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20134208110001)
文摘We investigate the properties of thermal quantum correlations in an infinite spin-1/2 Ising-Heisenberg diamond chain with Dzyaloshinskii-Moriya（DM） interaction. The thermal quantum discord（TQD） and the thermal entanglement（TE）are discussed as two kinds of important methods to measure the quantum correlation, respectively. It is found that DM interaction plays an important role in the thermal quantum correlations of the system. It can enhance the thermal quantum correlations by increasing DM interaction. Furthermore, the thermal quantum correlations can be promoted by tuning the external magnetic field and the Heisenberg coupling parameter in the antiferromagnetic system. It is shown that the behaviors of TQD differ from those of TE. TQD is more robust against decoherence than TE. For the measurement of TQD, the ＂regrowth＂ phenomenon occurs in the ferromagnetic system. We also find that the anisotropy favors the thermal quantum correlations of the system with weak DM interaction.
基金Project supported by the National Natural Science Foundation of China(Grant No.11274102)the New Century Excellent Talents in University of Ministry of Education of China(Grant No.NCET-11-0960)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20134208110001)
文摘We investigate the thermal entanglement of the spin-1 Ising-Heisenberg diamond chain, which can be regarded as a theoretical model for the homometallic molecular ferrimagnet [Ni_3（C_4H_2O_4）_2-（μ_3-OH）_2（H_2O）_4]n ·（2H_2O）n. Two cases,i.e., the isotropic Heisenberg（Ising-XXX） coupling model and anisotropic Heisenberg（Ising-XXZ） coupling model, are discussed respectively. The negativity is chosen as the measurement of the thermal entanglement. By means of the transfermatrix approach, we focus on the effects of biquadratic interaction parameters on the negativity of the infinite spin-1 Ising-Heisenberg diamond chain. In the Ising-XXX coupling model, it is shown that for the case with ferromagnetic coupling the thermal entanglement can be induced by the biquadratic interaction, but the external magnetic field will suppress the occurrence of the entanglement induced by the biquadratic interaction. In the Ising-XXZ coupling model,for the case with antiferromagnetic coupling, due to the biquadratic interaction the effect of the anisotropy parameter on the entanglement will be suppressed at near-zero temperature. Moreover, the biquadratic interaction makes the threshold temperature increase. The effects of the external magnetic field on the thermal entanglement are also discussed, and it is observed that the entanglement revival phenomena exist in both models considered.
基金supported by the National Natural Science Foundation of China(Grant No.11274102)the New Century Excellent Talents in University of Ministry of Education of China(Grant No.NCET-11-0960)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20134208110001)
文摘We investigate the thermal entanglement in a spin-l/2 Ising-Heisenberg diamond chain, in which the vertical Heisen- berg spin dimers alternate with single Ising spins. Due to the fact that the Dzyaloshinskii-Moriya （DM） interaction con- tributes to unusual and interesting magnetic properties in actual materials, and moreover it plays a significant role in the degree of the entanglement of the Heisenberg quantum spin systems, we focus on the effects of different DM interactions, including Dz and Dx, on the thermal entanglement of the Heisenberg spin dimer. The concurrence, as a measure of spin dimer entanglement, is calculated for different values of exchange interactions, DM interaction, external magnetic field, and temperature. It is found that the critical temperature and the critical magnetic field corresponding to the vanishing of entanglement increase with DM interaction, and the entanglement revival region gets larger by increasing DM interac- tion, thus DM interaction favors the formation of the thermal entanglement. It is observed that different DM interaction parameters （Dz and Dx） have remarkably different influences on the entanglement. Different from the case Dz, there is the non-monotonic variation of the concurrence with temperature in the case Dx, and additionally the DM interaction Dx can induce the entanglement near zero temperature in the case that the antiferromagnetic Ising-type interaction constant is larger than the antiferromagnetic Heisenberg interaction constant. It is also shown that for the same value of DM interaction the critical magnetic field of the case Dx is larger than that of the case Dz.
基金Project supported by the Shanghai Leading Academic Disciplines Project,China (Grant No. T0104)the National Natural Science Foundation of China(Grant No. 10674092)
文摘The magnetic properties of a mixed spin-2 and spin-1/2 ferromagnetic diamond chain are studied by effective-field theory and Monte Carlo（MC） simulation based on the Ising model.The temperature dependences of magnetization,magnetic susceptibility,internal energy,and specific heat are studied,respectively.The exchange interaction dependences of magnetization and the critical temperature are calculated by MC simulation.The changes of magnetization depending on the field increasing and then the field decreasing under steady-static conditions are also given.
基金Supported by the Azerbaijan Shahid Madani University
文摘We consider an entangled Ising-XY Z diamond chain structure. Quantum correlations for this model are inves- tigated by using quantum discord and trace distance discord. Quantum correlations are obtained for different values of the anisotropy parameter, magnetic field and temperature. By comparison between quantum correlations, we show that the trace distance discord is always larger than quantum discord. Finally, some novel effects such as increasing the quantum correlations with temperature and constructive role of anisotropy parameter, which may play to the quantum correlations, are observed.
