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arXiv · 0810.4461

Hyperentanglement of two photons in three degrees of freedom

G. Vallone·R. Ceccarelli·F. De Martini·P. Mataloni
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Abstract

A 6-qubit hyperentangled state has been realized by entangling two photons in three degrees of freedom. These correspond to the polarization, the longitudinal momentum and the indistinguishable emission produced by a 2-crystal system operating with Type I phase matching in the spontaneous parametric down conversion regime. The state has been characterized by a chained interferometric apparatus and its complete entangled nature has been tested by a novel witness criterium specifically introduced for hyperentangled states. The experiment represents the first realization of a genuine hyperentangled state with the maximum entanglement between the two particles allowed in the given Hilbert space.

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G. Vallone, R. Ceccarelli, F. De Martini, P. Mataloni. 2008-10-24. Hyperentanglement of two photons in three degrees of freedom. https://doi.org/10.1103/physreva.79.030301

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