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Identifying two-photon high-dimensional entanglement in transverse patterns

Gui-Fang Dang·Li-Ping Deng·Kaige Wang
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Abstract

We propose a scheme to explore two-photon high-dimensional entanglement associated with a transverse pattern by means of two-photon interference in a beamsplitter. We find that the topological symmetry of the angular spectrum of the two-photon state governs the nature of the two-photon interference. We prove that the anti-coalescence interference is the signature of two-photon entanglement. On the basis of this feature, we propose a special Mach-Zehnder interferometer incorporated with two spiral phase plates which can change the interference from a coalescence to an anti-coalescence type only for a two-photon entangled state. The scheme is simple and straightforward compared with the test for a Bell inequality.

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Gui-Fang Dang, Li-Ping Deng, Kaige Wang. 2005-04-08. Identifying two-photon high-dimensional entanglement in transverse patterns. https://doi.org/10.1016/j.physleta.2006.06.085

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