1204.0366 (Alastair Kay)

Using Separable Bell-Diagonal States to Distribute Entanglement    [PDF]

Alastair Kay

One of the many bizarre features of entanglement is that Alice, by sending a qubit to Bob in a separable state, can generate some entanglement between herself and Bob. We strip this protocol down to the bare essentials, allowing us to focus on the key properties of the initial resource state that enable this entanglement distribution. We prove the necessary and sufficient conditions under which the correlations of a Bell-diagonal state serve as a useful resource, contrasting this with the discord, recently shown to bound the entanglement that can be distributed.

View original: http://arxiv.org/abs/1204.0366