Quantum correlation dynamics of three non-coupled two-level atoms in different reservoirs

Time evolution dynamics of three non-coupled two-level atoms independently interacting with their reservoirs is solved exactly by considering a damping Lorentzian spectral density. For three atoms initially prepared in Greenberger-Horne-Zeilinger-type state, quantum correlation dynamics in a Markovian reservoir is compared with that in a non-Markovian reservoir. By increasing detuning quantity in the non-Markovian reservoir, three-atom correlation dynamics measured by negative eigenvalue presents a trapping phenomenon which provides long-time quantum entanglement. Then we compare the correlation dynamics of three atoms with that of two atoms, measured by quantum entanglement and quantum discord for an initial robuster-entangled type state. The result further confirms that quantum discord is indeed different from quantum entanglement in identifying quantum correlation of many bodies.