TY - UNPB

T1 - Non-Markovian Reactivation of Quantum Relays

AU - Pirandola, Stefano

AU - Ottaviani, Carlo

AU - Jacobsen, Christian S.

AU - Spedalieri, Gaetana

AU - Braunstein, Samuel L.

AU - Gehring, Tobias

AU - Andersen, Ulrik L.

PY - 2015/5/27

Y1 - 2015/5/27

N2 - We consider a quantum relay which is used by two parties to perform several continuous-variable protocols: Entanglement swapping, distillation, quantum teleportation, and quantum key distribution. The theory of these protocols is extended to a non-Markovian model of decoherence characterized by correlated Gaussian noise. Even if bipartite entanglement is completely lost at the relay, we show that the various protocols can progressively be reactivated by the separable noise-correlations of the environment. In fact, above a critical amount, these correlations are able to restore the distribution of quadripartite entanglement, which can be localized into an exploitable bipartite form by the action of the relay. Our findings are confirmed by a proof-of-principle experiment and show the potential advantages of non-Markovian effects in a quantum network architecture.

AB - We consider a quantum relay which is used by two parties to perform several continuous-variable protocols: Entanglement swapping, distillation, quantum teleportation, and quantum key distribution. The theory of these protocols is extended to a non-Markovian model of decoherence characterized by correlated Gaussian noise. Even if bipartite entanglement is completely lost at the relay, we show that the various protocols can progressively be reactivated by the separable noise-correlations of the environment. In fact, above a critical amount, these correlations are able to restore the distribution of quadripartite entanglement, which can be localized into an exploitable bipartite form by the action of the relay. Our findings are confirmed by a proof-of-principle experiment and show the potential advantages of non-Markovian effects in a quantum network architecture.

KW - quant-ph

KW - cond-mat.other

KW - physics.optics

M3 - Preprint

SP - 1

EP - 7

BT - Non-Markovian Reactivation of Quantum Relays

ER -