×

Thermal and non-uniform magnetic quantum discord in the two-qubit Heisenberg XXZ model. (English) Zbl 1257.81010

Summary: The thermal quantum discord (QD) is investigated in the two-qubit anisotropic Heisenberg XXZ model under an external non-uniform magnetic field along the \(Z\)-axis. We obtain the analytical expressions of the thermal QD and thermal entanglement measured by concurrence (C). It shows that for any temperature \(T\), QD gradually decreases with the increase of non-uniform magnetic field \(|b|\), in some regions where C increases while QD decreases. It is also found that thermal quantum discord does not vanish at finite temperatures, but concurrence vanishes completely at a critical temperature. It is shown that for a higher value of \(J_Z\), the system has a stronger QD. There is a critical magnetic field \(B_c\), which increases with the increasing \(b\). QD decay monotonically (for \(B < B_c\)) when temperature \(T\) increases, or initially increases to some peaks and then decrease (for \(B > B_c\)).

MSC:

81P40 Quantum coherence, entanglement, quantum correlations
81P45 Quantum information, communication, networks (quantum-theoretic aspects)
82B20 Lattice systems (Ising, dimer, Potts, etc.) and systems on graphs arising in equilibrium statistical mechanics
PDFBibTeX XMLCite
Full Text: DOI

References:

[1] Nielsen M. A., Quantum Computation and Quantum Information (2000) · Zbl 1049.81015
[2] DOI: 10.1103/RevModPhys.81.865 · Zbl 1205.81012 · doi:10.1103/RevModPhys.81.865
[3] DOI: 10.1103/PhysRevA.72.042316 · doi:10.1103/PhysRevA.72.042316
[4] DOI: 10.1103/PhysRevLett.100.050502 · doi:10.1103/PhysRevLett.100.050502
[5] DOI: 10.1103/PhysRevLett.101.200501 · doi:10.1103/PhysRevLett.101.200501
[6] DOI: 10.1103/PhysRevLett.88.017901 · Zbl 1255.81071 · doi:10.1103/PhysRevLett.88.017901
[7] DOI: 10.1103/PhysRevA.67.012320 · doi:10.1103/PhysRevA.67.012320
[8] DOI: 10.1088/0305-4470/34/35/315 · Zbl 0988.81023 · doi:10.1088/0305-4470/34/35/315
[9] DOI: 10.1209/0295-5075/88/50003 · doi:10.1209/0295-5075/88/50003
[10] DOI: 10.1103/PhysRevB.78.224413 · doi:10.1103/PhysRevB.78.224413
[11] DOI: 10.1103/PhysRevA.80.022108 · doi:10.1103/PhysRevA.80.022108
[12] DOI: 10.1103/PhysRevA.80.024103 · doi:10.1103/PhysRevA.80.024103
[13] DOI: 10.1103/PhysRevA.81.052107 · doi:10.1103/PhysRevA.81.052107
[14] DOI: 10.1103/PhysRevA.77.022301 · doi:10.1103/PhysRevA.77.022301
[15] DOI: 10.1103/PhysRevA.81.042105 · doi:10.1103/PhysRevA.81.042105
[16] DOI: 10.1103/PhysRevA.57.120 · doi:10.1103/PhysRevA.57.120
[17] DOI: 10.1103/PhysRevB.59.2070 · doi:10.1103/PhysRevB.59.2070
[18] DOI: 10.1103/PhysRevA.68.044301 · doi:10.1103/PhysRevA.68.044301
[19] DOI: 10.1142/S021798490400761X · Zbl 1071.82518 · doi:10.1142/S021798490400761X
[20] DOI: 10.1103/PhysRevA.72.034302 · doi:10.1103/PhysRevA.72.034302
[21] DOI: 10.1103/PhysRevA.71.022308 · doi:10.1103/PhysRevA.71.022308
[22] DOI: 10.1103/PhysRevA.81.044101 · doi:10.1103/PhysRevA.81.044101
[23] Wang Q., Chin. Phys. B 19 pp 100311–
[24] DOI: 10.1016/j.aop.2011.05.002 · Zbl 1269.81019 · doi:10.1016/j.aop.2011.05.002
[25] Ali S. M., J. Phys. A: Math. Theor. 43 pp 485302–
[26] DOI: 10.1103/PhysRevA.61.062301 · doi:10.1103/PhysRevA.61.062301
[27] DOI: 10.1103/PhysRevLett.86.918 · doi:10.1103/PhysRevLett.86.918
[28] DOI: 10.1103/RevModPhys.73.357 · doi:10.1103/RevModPhys.73.357
[29] DOI: 10.1103/PhysRevLett.78.5022 · doi:10.1103/PhysRevLett.78.5022
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.