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Orbital entanglement and violation of Bell inequalities in mesoscopic conductors

P. Samuelsson·E. V. Sukhorukov·M. Buttiker
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Abstract

We propose a spin-independent scheme to generate and detect two-particle entanglement in a mesoscopic normal-superconductor system. A superconductor, weakly coupled to the normal conductor, generates an orbitally entangled state by injecting pairs of electrons into different leads of the normal conductor. The entanglement is detected via violation of a Bell inequality, formulated in terms of zero-frequency current cross-correlators. It is shown that the Bell inequality can be violated for arbitrary strong dephasing in the normal conductor.

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P. Samuelsson, E. V. Sukhorukov, M. Buttiker. 2003-03-25. Orbital entanglement and violation of Bell inequalities in mesoscopic conductors. https://doi.org/10.1103/physrevlett.91.157002

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