Different entanglement dynamical behaviors due to initial system-environment correlations

We theoretically analyze the roles of initial correlations between a two-qubit system and a structured environment on entanglement dynamics of these two qubits. Considering two initial system-environment correlations, we show that the system-environment quantum correlation can initially increase the two-qubit entanglement, and the system-environment classical correlation would lead to the initially decreased two-qubit entanglement. Different two-qubit entanglement dynamics can be induced by these two initial system-environment correlations. However, under a certain condition, the roles of these two initial system-environment correlations on the two-qubit entanglement are the same.