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arXiv · 0803.1897

An elementary optical gate for expanding entanglement web

Toshiyuki Tashima·Sahin Kaya Ozdemir·Takashi Yamamoto·Masato Koashi·Nobuyuki Imoto
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Abstract

We introduce an elementary optical gate for expanding polarization entangled W states, in which every pair of photons are entangled alike. The gate is composed of a pair of 50:50 beamsplitters and ancillary photons in the two-photon Fock state. By seeding one of the photons in an $n$-photon W state into this gate, we obtain an $(n+2)$-photon W state after post-selection. This gate gives a better efficiency and a simpler implementation than previous proposals for $\rm W$-state preparation.

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Toshiyuki Tashima, Sahin Kaya Ozdemir, Takashi Yamamoto, Masato Koashi, Nobuyuki Imoto. 2008-03-13. An elementary optical gate for expanding entanglement web. https://doi.org/10.1103/physreva.77.030302

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