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arXiv · 0805.1924

Extrinsic orbital angular momentum of entangled photon-pairs in spontaneous parametric down-conversion

Sheng Feng·Prem Kumar
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Abstract

Starting from the standard Hamiltonian describing the optical non-linear process of spontaneous parametric down-conversion, we theoretically show that the generated entangled photon-pairs carry non-negligible orbital angular momentum in the degrees of freedom of relative movement in the type-II cases due to spatial symmetry breaking. We also show that the orbital angular momentum carried by photon-pairs in these degrees of freedom escapes detection in the traditional measurement scheme, which demands development of new techniques for further experimental investigations.

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Sheng Feng, Prem Kumar. 2008-10-07. Extrinsic orbital angular momentum of entangled photon-pairs in spontaneous parametric down-conversion. https://arxiv.org/abs/0805.1924

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