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Research in Optical Sciences

Advanced Quantum Communication via Hyperentanglement

Paul G. Kwiat

Published Jan 1, 2012• 1 citation
Publisher

Abstract

Photons created via spontaneous downconversion may be simultaneously entangled in multiple degrees of freedom. This ‘hyperentanglement’ enables advanced capabilities in quantum communication, including multi-bit per photon quantum cryptography and superdense quantum teleportation.
DOI
10.1364/qim.2012.qw1a.1

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Multidimensional entangled photon states represent a useful resource for large-scale quantum communication networks. By leveraging multiple degrees of freedom (DoFs) of photons, the dimensionality of the Hilbert space can be expanded without increasing the number of particles, enhancing the efficiency of quantum information processing. Specifically, hyperentanglement, i.e. simultaneous entanglement across multiple DoFs, is robust against decoherence, thus providing strengthened performance in noisy quantum communication protocols with respect to n-photon quantum states [1].