Entanglement in Mesoscopic Structures: Role of Projection

TL;DR

This paper theoretically investigates how entanglement arises in mesoscopic structures through beam splitter-induced correlations, emphasizing the roles of fermionic statistics and projective measurements in generating spin-entangled electrons.

Contribution

It introduces a model demonstrating entanglement generation in non-interacting mesoscopic systems via polarized sources and beam splitters, highlighting the importance of projection and fermionic statistics.

Findings

Bell inequality violation indicates entanglement presence.

Projection and fermionic statistics are crucial for entanglement generation.

Tunable correlations enable control over entanglement in mesoscopic devices.

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.