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Entanglement in Mesoscopic Structures: Role of Projection

A. V. Lebedev·G. Blatter·C. W. J. Beenakker·G. B. Lesovik
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Abstract

We present a theoretical analysis of the appearance of entanglement in non-interacting mesoscopic structures. Our setup involves two oppositely polarized sources injecting electrons of opposite spin into the two incoming leads. The mixing of these polarized streams in an ideal four-channel beam splitter produces two outgoing streams with particular tunable correlations. A Bell inequality test involving cross-correlated spin-currents in opposite leads signals the presence of spin-entanglement between particles propagating in different leads. We identify the role of fermionic statistics and projective measurement in the generation of these spin-entangled electrons.

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A. V. Lebedev, G. Blatter, C. W. J. Beenakker, G. B. Lesovik. 2003-12-07. Entanglement in Mesoscopic Structures: Role of Projection. https://doi.org/10.1103/physrevb.69.235312

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