Quantification of entanglement via uncertainties

Multi - particle entanglement via two - party entanglement ∗

Entanglement between n particles is a generalization of the entanglement between two particles, and a state is considered entangled if it cannot be written as a mixture of tensor products of the n particles’ states. We present the key notion of semi-separability, used to investigate n-particle entanglement by looking at two-party entanglement between its various subsystems. We provide necessary...

Optimal entanglement purifying via entanglement swapping

It is known that entanglement swapping can be used to realize entanglement purifying. By this way, two particles belong to different non-maximally entangled pairs can be projected probabilisticly to a maximally entangled state or to a less entangled state. In this report, we show, when the less entangled state is obtained, if a unitary transformation is introduced locally, then a maximally enta...

Device-independent entanglement quantification and related applications.

We present a general method to quantify both bipartite and multipartite entanglement in a device-independent manner, meaning that we put a lower bound on the amount of entanglement present in a system based on the observed data only but independent of any quantum description of the employed devices. Some of the bounds we obtain, such as for the Clauser-Horne-Shimony-Holt Bell inequality or the ...

Quantum Entanglement: Detection, Classification, and Quantification

Entanglement quantification by local unitary operations

A. Monras,1 G. Adesso,2 S. M. Giampaolo,1 G. Gualdi,1 G. B. Davies,2 and F. Illuminati1,* 1Dipartimento di Matematica e Informatica, Università degli Studi di Salerno, CNISM, Unità di Salerno, and INFN, Sezione di Napoli-Gruppo Collegato di Salerno, Via Ponte don Melillo, I-84084 Fisciano (SA), Italy 2School of Mathematical Sciences, University of Nottingham, University Park, Nottingham NG7 2RD...