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arXiv:quant-ph/9911109 · Physical Review Letters

Quantum Cryptography Using Entangled Photons in Energy-Time Bell States

Wolfgang Tittel, Jurgen Brendel, Hugo Zbinden, Nicolas Gisin

Published May 15, 2000• 582 citations
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Abstract

We present a setup for quantum cryptography based on photon pairs in energy-time Bell states and show its feasibility in a laboratory experiment. Our scheme combines the advantages of using photon pairs instead of faint laser pulses and the possibility to preserve energy-time entanglement over long distances. Moreover, using four-dimensional energy-time states, no fast random change of bases is required in our setup: Nature itself decides whether to measure in the energy or in the time base, thus rendering eavesdropper attacks based on "photon number splitting" less efficient.

DOI
10.1103/physrevlett.84.4737

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