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arXiv · 0810.2417

Quantum information transfer from spin to orbital angular momentum of photons

Eleonora Nagali·Fabio Sciarrino·Francesco De Martini·Lorenzo Marrucci·Bruno Piccirillo·Ebrahim Karimi·Enrico Santamato
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Abstract

The optical "spin-orbit" coupling occurring in a suitably patterned nonuniform birefringent plate known as `q-plate' allows entangling the polarization of a single photon with its orbital angular momentum (OAM). This process, in turn, can be exploited for building a bidirectional "spin-OAM interface", capable of transposing the quantum information from the spin to the OAM degree of freedom of photons and \textit{vice versa}. Here, we experimentally demonstrate this process by single-photon quantum tomographic analysis. Moreover, we show that two-photon quantum correlations such as those resulting from coalescence interference can be successfully transferred into the OAM degree of freedom.

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Eleonora Nagali, Fabio Sciarrino, Francesco De Martini, Lorenzo Marrucci, Bruno Piccirillo, Ebrahim Karimi, Enrico Santamato. 2008-10-14. Quantum information transfer from spin to orbital angular momentum of photons. https://doi.org/10.1103/physrevlett.103.013601

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