# Bell inequality violation with two remote atomic qubits.

@article{Matsukevich2008BellIV,
title={Bell inequality violation with two remote atomic qubits.},
author={Dzmitry N. Matsukevich and Peter Maunz and David L. Moehring and Steven Matthew Olmschenk and Christopher R. Monroe},
journal={Physical review letters},
year={2008},
volume={100 15},
pages={
150404
}
}
We observe violation of a Bell inequality between the quantum states of two remote Yb+ ions separated by a distance of about 1 m with the detection loophole closed. The heralded entanglement of two ions is established via interference and joint detection of two emitted photons, whose polarization is entangled with each ion. The entanglement of remote qubits is also characterized by full quantum state tomography.
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