Robustness investigation on geometric quantum discord of coupled qubits initially in maximally entangled mixed states

Abstract

Abstract: Geometric quantum discord is a measure of quantum correlations. Combining quantum entanglement and geometric quantum discord, we investigate the comparison of quantum correlations of two-qubits initially in X-state in non-Markovian process. The results show, by using analytical and numerical methods, in some initial states, both the concurrence and the geometric quantum discord will decay because of the existence of the dissipation environments. However, the geometric quantum discord damps slowly than concurrence does, which shows the survival time of geometric quantum discord longer than of the entanglement. In other words, geometric quantum discord is more robust than entanglement to against the relaxation processes. Therefore, the quantum correlation is also a useful resource to realize quantum information processing.

Key words: quantum correlation, concurrence, geometric Quantum discord, coupled qubits

CLC Number:

O431.2

HU Yan, YU Yan-xia, JI Ying-hua . Robustness investigation on geometric quantum discord of coupled qubits initially in maximally entangled mixed states[J]. J4, 2013, 30(5): 572-578.

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