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Bell inequalities and entanglement in solid state devices

Nikolai M. Chtchelkatchev·Gianni Blatter·Gordey B. Lesovik·Thierry Martin
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Abstract

Bell-inequality checks constitute a probe of entanglement -- given a source of entangled particles, their violation are a signature of the non-local nature of quantum mechanics. Here, we study a solid state device producing pairs of entangled electrons, a superconductor emitting Cooper pairs properly split into the two arms of a normal-metallic fork with the help of appropriate filters. We formulate Bell-type inequalities in terms of current-current cross-correlators, the natural quantities measured in mesoscopic physics; their violation provides evidence that this device indeed is a source of entangled electrons.

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Nikolai M. Chtchelkatchev, Gianni Blatter, Gordey B. Lesovik, Thierry Martin. 2002-02-24. Bell inequalities and entanglement in solid state devices. https://doi.org/10.1103/physrevb.66.161320

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