Robustness of quantum correlations against decoherence

We study dynamics of nonclassical correlations by exactly solving a model consisting of two atomic qubits with spontaneous emission. We find that the nonclassical correlations defined by different measures give different qualitative characterizations of those correlations. The relative behaviors of those correlation measures are presented explicitly for various quantum states in the two-qubit atomic system. In particular, we find that the robustness of quantum correlations can be greatly enhanced by performing appropriate local unitary operations on the initial state of the system.

► Comparative study of different quantum correlation measures. ► Quantum states manifesting the relativity of different correlation measures. ► Enhance robustness of quantum correlations by local unitary operations. ► Disagreement of QD and GMQD on reflecting sudden change behaviors of correlations.