Effects of classical environmental noise on entanglement and quantum discord dynamics

We address the effect of classical noise on the dynamics of quantum correlations, entanglement and quantum discord (QD), of two non-interacting qubits initially prepared in a Bell state. The effect of noise is modeled by randomizing the single-qubit transition amplitudes. We address both static and dynamic environmental noise corresponding to interaction with separate and common baths in either Markovian and non-Markovian regimes. In the Markov regime, a monotone decay of the quantum correlations is found, whereas for non-Markovian noise sudden death and revival phenomena may occur, depending on the characteristics of the noise. En- tanglement and QD show the same qualitative behavior for all kind of noises considered. On the other hand, we ̄nd that separate and common environments may play opposite roles in pre- serving quantum correlations, depending on the noise regime considered.