Protecting quantum entanglement in thermal reservoir by detuning

In this work, the quantum entanglement dynamics of a two-atom system in the thermal reservoir is investigated. An analytical solution of the single atom in the thermal reservoir and the expression of the quantum entanglement of the two-atom system in the thermal reservoir are obtained by the Markovian master equation method. The results showed that the nonzero temperature leads to sudden death of entanglement under the weak coupling limit. The higher the temperature, the faster the decay of entanglement. In particular, the detuning and the smaller spectrum width in the weak atom-reservoir coupling regime can effectively protect the quantum entanglement of the two-atom system in the thermal reservoir under the weak atom-reservoir coupling regime. The corresponding physical explanation is given by the entropy production rare.