Quantum discord dynamics of two atoms under different quantum feedbacks

The dynamics of two identical atoms is studied, which is resonantly coupled to a single-mode cavity under two different quantum feedback controls, i.e., the symmetric feedback control and the nonsymmetric feedback control. Correspondingly, the quantum discord of the system is induced to reach steady values under these two kinds of feedback controls. Furthermore, in some cases, the steady value of quantum discord of the system under symmetric feedback control is much larger than the steady value under nonsymmetric feedback control. The situation is just the opposite when the initial state is |eg〉. It is also found that the feedback is not good for getting a high discord when the initial state is in the form of Werner-like state (d = 0).