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Pulsed energy-time entangled twin-photon source for quantum communication

J. Brendel·N. Gisin·W. Tittel·H. Zbinden
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Abstract

A pulsed source of energy-time entangled photon pairs pumped by a standard laser diode is proposed and demonstrated. The basic states can be distinguished by their time of arrival. This greatly simplifies the realization of 2-photon quantum cryptography, Bell state analyzers, quantum teleportation, dense coding, entanglement swapping, GHZ-states sources, etc. Moreover the entanglement is well protected during photon propagation in telecom optical fibers, opening the door to few-photon applications of quantum communication over long distances.

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J. Brendel, N. Gisin, W. Tittel, H. Zbinden. 1998-09-11. Pulsed energy-time entangled twin-photon source for quantum communication. https://doi.org/10.1103/physrevlett.82.2594

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