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Updated: Mar 14, 2026

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Multipartite Entanglement of a Two-Separable State
S Gerke1, J Sperling1,2, W Vogel1
1Arbeitsgruppe Theoretische Quantenoptik, Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
Abstract:
We consider a six-partite, continuous-variable quantum state that we have effectively generated by the parametric down-conversion of a femtosecond frequency comb. We show that, though this state is two-separable, i.e., it does not exhibit "genuine entanglement," it is undoubtedly multipartite entangled. The consideration of not only the entanglement of individual mode decompositions, but also of combinations of those, solves the puzzle and exemplifies the importance of studying different categories of multipartite entanglement.
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