Quantum discord dynamics in the presence of initial system-cavity correlations

We analyse the roles of initial correlations between a two-qubit system and a dissipative cavity on quantum discord dynamics of two qubits. Considering two initial system-cavity states, we find that the initial system-cavity correlations not only initially increase the two-qubit quantum discord but also lead to a larger long-time quantum discord asymptotic value. Moreover, quantum discord due to initial correlations is more robust than the case of the initial factorized state. Finally, we show the initial correlations' importance for dynamic behaviour of mutual information and classical correlation.