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arXiv · 0912.2975

Demonstration of a programmable source of two-photon multiqubit entangled states

Simone Cialdi·Davide Brivio·Matteo G. A. Paris
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Abstract

We suggest and demonstrate a novel source of two-photon multipartite entangled states which exploits the transverse spatial structure of spontaneous parametric downconversion together with a programmable spatial light modulator (SLM). The 1D SLM is used to perform polarization entanglement purification and to realize arbitrary phase-gates between polarization and momentum degrees of freedom of photons. We experimentally demonstrate our scheme by generating two-photon three qubit linear cluster states with high fidelity using a diode laser pump with a limited coherence time and power on the crystal as low as 2.5$mW.

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Simone Cialdi, Davide Brivio, Matteo G. A. Paris. 2010-03-25. Demonstration of a programmable source of two-photon multiqubit entangled states. https://doi.org/10.1103/physreva.81.042322

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