Quantum correlations between each qubit in a two-atom system and the environment in terms of interatomic distance

摘要

The quantum correlations between a qubit and its environment are described quantitatively in terms ofninteratomic distance. Specifically, considering a realistic system of two two-level atoms and taking into account thendipole-dipole interaction and collective damping, the quantum entanglement and quantum discord are investigatednduring the dissipative process as functions of the interatomic distance. For atoms that are initially maximallynentangled, it turns out that there is a critical distance at which each atom is maximally quantum correlated withnits environment. Counterintuitively, the approach of the two atoms can maximize the entanglement between eachnone and the environment and, even at the same distance, minimize the loss of entanglement between the pair.