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arXiv · 0809.4575

Multi-path entanglement of two photons

A. Rossi·G. Vallone·A. Chiuri·F. De Martini·P. Mataloni
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Abstract

We present a novel optical device based on an integrated system of micro-lenses and single mode optical fibers. It allows to collect and direct into many modes two photons generated by spontaneous parametric down conversion. By this device multiqubit entangled states and/or multilevel qu-$d$it states of two photons, encoded in the longitudinal momentum degree of freedom, are created. The multi-path photon entanglement realized by this device is expected to find important applications in modern quantum information technology.

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A. Rossi, G. Vallone, A. Chiuri, F. De Martini, P. Mataloni. 2009-02-23. Multi-path entanglement of two photons. https://doi.org/10.1103/physrevlett.102.153902

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