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arXiv:quant-ph/9809034 · Physical Review Letters

Pulsed Energy-Time Entangled Twin-Photon Source for Quantum Communication

Jurgen Brendel, Nicolas Gisin, Wolfgang Tittel, Hugo Zbinden

Published Mar 22, 1999• 679 citations
arXivHTMLPDF

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.

DOI
10.1103/physrevlett.82.2594

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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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