Geometry of Faithful Entanglement

Faithful Squashed Entanglement

Squashed entanglement is a measure for the entanglement of bipartite quantum states. In this paper we present a lower bound for squashed entanglement in terms of a distance to the set of separable states. This implies that squashed entanglement is faithful, that is, it is strictly positive if and only if the state is entangled. We derive the lower bound on squashed entanglement from a lower bou...

Faithful Teleportation with Genuine Multipartite Entanglement

In this letter we present an explicit protocol B2 for faithfully teleporting an arbitrary 2-qubit state with a class of 4-qubit entangled states. We construct these states in a way different from that of Yeo and Chua [Phys. Rev. Lett. 94, 060502 (2006)]. We will show that the genuine states presented by Yeo and Chua are only a subset of our entangled states. The generalizations of the protocol ...

Purification of noisy entanglement and faithful teleportation via noisy channels.

Charles H. Bennett(1) , Gilles Brassard(2), Sandu Popescu(3), Benjamin Schumacher(4), John A. Smolin(5), and William K. Wootters(6) (1) IBM Research Division, Yorktown Heights, NY 10598; (2) D epartement IRO, Universit e de Montr eal, C.P. 6128, Succursale centre{ville, Montr eal (Qu ebec), Canada H3C 3J7; (3) Physics Department, Tel Aviv University, Tel Aviv, Israel; (4) Physics Department, Ke...

Quantum Entanglement and Geometry

Faithful entanglement swapping based on sum-frequency generation.

We show that an entanglement swapping operation performed with spontaneous parametric down-conversion can be made faithful without postselection using sum-frequency generation. This invites us to revisit the sum-frequency process and from a proof-of-principle experiment, we demonstrate that it provides a realistic solution for nonlinear optics at the single-photon level. This opens the way to a...