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Non-local generation of entanglement of photons which do not meet each other

Juergen Roesch·Xian-Min Jing·Juan Yin·Tao Yang·Jian-Wei Pan
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Abstract

We report for the first time in an ancilla-free process a non-local entanglement between two single photons which do not meet. For our experiment we derive a simple and efficient method to entangle two single photons using post-selection technology. The photons are guided into an interferometer setup without the need for ancilla photons for projection into the Bell-states. After passing the output ports, the photons are analyzed using a bell state analyzer on each side. The experimental data clearly shows a non-local interaction between these photons, surpassing the limit set by the CHSH-inequality with an S-value of 2.54 and 24 standard deviations.

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Juergen Roesch, Xian-Min Jing, Juan Yin, Tao Yang, Jian-Wei Pan. 2006-09-18. Non-local generation of entanglement of photons which do not meet each other. https://arxiv.org/abs/quant-ph/0609135

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