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Four-dimensional Quantum Key Distribution using Position-Momentum and Polarization Correlations

M. P. Almeida·S. P. Walborn·P. H. Souto Ribeiro
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Abstract

We demonstrate experimentally that it is possible to prepare and detect photon pairs created by spontaneous parametric down-conversion which exhibit simultaneous position-momentum and polarization correlations that are adequate to implement a four-dimensional key distribution protocol.

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M. P. Almeida, S. P. Walborn, P. H. Souto Ribeiro. 2005-10-12. Four-dimensional Quantum Key Distribution using Position-Momentum and Polarization Correlations. https://arxiv.org/abs/quant-ph/0510087

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