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arXiv · 1211.5907

Decoherence effect on quantum correlation and entanglement in a two-qubit spin chain

Mohammad Reza Pourkarimi·Majid Rahnama·Hossein Rooholamini
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Abstract

Assuming a two-qubit system in Werner state which evolves in Heisenberg XY model with Dzyaloshinskii-Moriya (DM) interaction under the effect of different environments. We evaluate and compare quantum entanglement, quantum and classical correlation measures. It is shown that in the absence of decoherence effects, there is a critical value of DM interaction for which entanglement may vanish while quantum and classical correlations do not. In the presence of environment the behavior of correlations depends on the kind of system-environment interaction. Correlations can be sustained by manipulating Hamiltonian anisotropic-parameter in a dissipative environment. Quantum and classical correlations are more stable than entanglement generally.

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Mohammad Reza Pourkarimi, Majid Rahnama, Hossein Rooholamini. 2012-11-26. Decoherence effect on quantum correlation and entanglement in a two-qubit spin chain. https://arxiv.org/abs/1211.5907

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