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arXiv · 0806.4216

Universal entangler with photon pairs in arbitrary states

Bing He·Yuhang Ren·Janos A. Bergou
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Abstract

We propose a setup that transforms a photon pair in arbitrary rank-four mixed state, which could also be unknown, to a Bell state. The setup involves two linear optical circuits processing the individual photons and a parity gate working with weak cross-Kerr nonlinearity. By the photon number resolving detection on one of the output quantum bus or communication beams, the setup will realize a near deterministic transformation to a Bell state for every entangling attempt. With the simple threshold detectors, on the other hand, the system can still reach a considerable success probability of 0.5 per try. The decoherence effect caused by photon absorption losses in the operation is also discussed.

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Bing He, Yuhang Ren, Janos A. Bergou. 2008-06-26. Universal entangler with photon pairs in arbitrary states. https://doi.org/10.1088/0953-4075/43/2/025502

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