SZFI Szeminárium
Szalay Szilárd
(Wigner FK SZFI)
Permutation invariant multipartite entanglement and correlations

We briefly review the partial separability based classification of mixed states of multipartite quantum systems of arbitrary number of subsystems, and show how this structure simplifies in the case when not entanglement but correlation is considered. As special cases, we consider the notions of k-separability and k-producibility (as well as their correlational versions), and reveal how these are dual to each other. This duality can be seen from a much wider perspective, when we consider the entanglement and correlational properties which are invariant under the permutations of the subsystems. This general treatment reveals a new property, which we call k-stretchability of entanglement, being sensitive in a balanced way to both the maximal size of correlated (or entangled) subsystems and the minimal number of subsystems uncorrelated (or separable) from one another. We also give the corresponding multipartite correlation and entanglement monotones, being the natural generalizations of mutual information, entanglement entropy and entanglement of formation or relative entropy of entanglement, showing the same lattice structure as the classification (multipartite monotonicity). As illustration, we show some examples coming from molecular physics.

2021. október 5. kedd, 10.00
Bldg.1, auditorium, https://teams.microsoft.com/l/meetup-join/19%3ace423c05cd1543ab9f9905886590ad69%40thread.tacv2/1633153083316?context=%7b%22Tid%22%3a%224d7ddeef-14ff-4911-8c11-401c69384d77%22%2c%22Oid%22%3a%22969d2d4a-5ba8-43f1-bd69-93f0998b025f%22%7d