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Robust long-distance entanglement and a loophole-free Bell test with ions and photons

Christoph Simon·William T. M. Irvine
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Abstract

Two trapped ions that are kilometers apart can be entangled by the joint detection of two photons, each coming from one of the ions, in a basis of entangled states. Such a detection is possible with linear optical elements. The use of two-photon interference allows entanglement distribution without interferometric sensitivity to the path length of the photons. The present method of creating entangled ions also opens up the possibility of a loophole-free test of Bell's inequalities.

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Christoph Simon, William T. M. Irvine. 2004-02-18. Robust long-distance entanglement and a loophole-free Bell test with ions and photons. https://doi.org/10.1103/physrevlett.91.110405

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