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The conservation of orbital angular momentum and the two-photon detection amplitude in spontaneous parametric down-conversion

Sheng Feng·Chao-Hsiang Chen·Geraldo A. Barbosa·Prem Kumar
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Abstract

We study the two-photon detection amplitude of the down-converted beams in spontaneous parametric down-conversion when the physical variable of orbital angular momentum is involved, taking into account both conservation and non-conservation of angular momentum. Agreeing with experimental observations, our theoretical calculation shows that spatial structure of the two-photon detection amplitude of the down-converted beams carries important information about conservation or non-conservation of orbital angular momentum in spontaneous parametric down-conversion.

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Sheng Feng, Chao-Hsiang Chen, Geraldo A. Barbosa, Prem Kumar. 2007-03-21. The conservation of orbital angular momentum and the two-photon detection amplitude in spontaneous parametric down-conversion. https://arxiv.org/abs/quant-ph/0703187

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