Scalability of GHZ and random-state entanglement in the presence of decoherence (2008)
Aolita, Leandro, Cavalcanti, Daniel, Acín, Antonio, Salles, Alejo, Tiersch, Markus, Buchleitner, Andreas, ...
We derive analytical upper bounds for the entanglement of generalized Greenberger-Horne-Zeilinger states coupled to locally depolarizing and dephasing environments, and for local thermal baths of...
Valerio Scarani, Antonio Acín, Grégoire Ribordy, Nicolas Gisin
cryptography protocols robust against photon number
Tests of multimode quantum non-locality with homodyne measurements (2008)
Acín, Antonio, Cerf, Nicolas J., Ferraro, Alessandro, Niset, Julien
We investigate the violation of local realism in Bell tests involving homodyne measurements performed on multimode continuous-variable states. By binning the measurement outcomes in an appropriate...
Quantum Non-locality and Partial Transposition for Continuous-Variable Systems (2008)
Salles, Alejo, Cavalcanti, Daniel, Acín, Antonio
A continuous-variable Bell inequality, valid for an arbitrary number of observers measuring observables with an arbitrary number of outcomes, was recently introduced in [Cavalcanti \emph{et al.},...
Grothendieck's constant and local models for noisy entangled quantum states (2006)
Acín, Antonio, Gisin, Nicolas, Toner, Benjamin
We relate the nonlocal properties of noisy entangled states to Grothendieck's constant, a mathematical constant appearing in Banach space theory. For two-qubit Werner states rhopW=p|psi–>
Optimal estimation of two-qubit pure-state entanglement (2000)
Acín, Antonio, Tarrach Siegel, Rolf, Vidal, Guifré
We present optimal measuring strategies for an estimation of the entanglement of unknown two-qubit pure states and of the degree of mixing of unknown single-qubit mixed states, of which N identical...