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The European Physical Journal D

Photon entanglement through linear optics networks with birefringent crystals

Ebrahim Ghasemian, Mohammad Kazem Tavassoly

Published Mar 1, 2021• 2 citations
Publisher
DOI
10.1140/epjd/s10053-021-00081-z

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The twin photons produced by a type‐II spontaneous parametric down conversion are well know as a potential source of photons for quantum teleportation due to the strong entanglement in polarization. This strong entanglement in polarization, however, depends on the spectral composition of the pump photon and the nature of optical isotropy of the crystal. By exact numerical calculation of the concurrence, we have shown that how pump photons spectral width and the birefringence nature of the crystal directly affect the degree of polarization entanglement of the twin photons.