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arXiv · 1411.3945

Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation

Simon E. Nigg·Rakesh P. Tiwari·Stefan Walter·Thomas L. Schmidt
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Abstract

Based on the Bardeen Cooper Schrieffer (BCS) theory of superconductivity, the coherent splitting of Cooper pairs from a superconductor to two spatially separated quantum dots has been predicted to generate nonlocal pairs of entangled electrons. In order to test this hypothesis, we propose a scheme to transfer the spin state of a split Cooper pair onto the polarization state of a pair of optical photons. We show that the produced photon pairs can be used to violate a Bell inequality, unambiguously demonstrating the entanglement of the split Cooper pairs.

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Simon E. Nigg, Rakesh P. Tiwari, Stefan Walter, Thomas L. Schmidt. 2015-03-30. Detecting nonlocal Cooper pair entanglement by optical Bell inequality violation. https://doi.org/10.1103/physrevb.91.094516

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