Entanglement manipulation of multipartite pure states with finite rounds of classical communication

We studied pure state transformations using local operations assisted by finitely many rounds of classical communication (LOCCN) [C. Spee, J. I. de Vicente, D. Sauerwein, and B. Kraus [Phys. Rev. Lett. (to be published)], arXiv: 1606.04418]. Here, we present the details of some of the proofs and generalize the construction of examples of state transformations via LOCCN which require a probabilistic step. However, we also present explicit examples of SLOCC classes where any separable transformation can be realized by a protocol in which each step is deterministic (all-det-LOCCN). Such transformations can be considered as natural generalizations of bipartite transformations. Furthermore, we provide examples of pure state transformations which are possible via separable transformations, but not via LOCCN. We also analyze an interesting genuinely multipartite effect which we call locking or unlocking the power of other parties. This means that one party can prevent or enable the implementation of LOCC transformations by other parties. Moreover, we investigate the maximally entangled set restricted to LOCCN and show how easily computable bounds on some entanglement measures can be derived by restricting to LOCCN.

Entanglement manipulation of multipartite pure states with finite rounds of classical communication Articles