We investigate the link between information and thermodynamics embodied by
Landauer's principle in the open dynamics of a multipartite quantum system.
Such irreversible dynamics is described in terms of a collisional model with a
finite temperature reservoir. We demonstrate that Landauer's principle holds,
for such a configuration, in a form that involves the flow of heat dissipated
into the environment and the rate of change of the entropy of the system. Quite
remarkably, such a principle for {\it heat and entropy power} can be explicitly
linked to the rate of creation of correlations among the elements of the
multipartite system and, in turn, the non-Markovian nature of their reduced
evolution. Such features are illustrated in two exemplary cases.Comment: 5 pages, 3 figures, RevTeX4-1; Accepted for publication in Phys. Rev.
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