Quantum correlations and thermal entanglement in a two-qubit Heisenberg XXZ model with external magnetic fields

Abstract

Abstract:

The quantum correlation of a two-qubit Heisenberg XXZ model has been investigated through applying two independent and controllable magnetic fields ( ) and ( ) on the two qubits respectively and changing the coupling parameter , magnetic field , inhomogeneous magnetic field and temperature . The behavior of quantum correlation and that of thermal entanglement under one and the same parameter is compared. The results show that quantum correlation can exist for a wider parameter range than thermal entanglement. In addition, for a certain region of parameter, quantum correlation and thermal entanglement exhibit completely different behaviors.

Key words: quantum optics, quantum correlation, thermal entanglement, quantum discord, Heisenberg XXZ model

CLC Number:

O431.2

XU Lin, XIA Yun-jie. Quantum correlations and thermal entanglement in a two-qubit Heisenberg XXZ model with external magnetic fields[J]. J4, 2012, 29(2): 185-191.

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