entanglement. To this end, we address an open system whose environment behaves either
as a quantal system or as an effective reservoir, depending on the regime chosen to rule the
system–environment dynamics. This allows us to study entanglement dynamics within
Markovian and non-Markovian regimes. We focus on the recently introduced definition of
quantum non-Markovianity that is based on the trace distance between pairs of initial states …