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arXiv:1503.07446 · Physical review. B./Physical review. B

Two-electron coherence and its measurement in electron quantum optics

É. Thibierge, Dario Ferraro, Benjamin Roussel, Clément Cabart, Arthur Marguerite, Gwendal Fève, Pascal Degiovanni

Published Feb 12, 2016• 15 citations
arXivHTMLPDF

Abstract

Engineering and studying few-electron states in ballistic conductors is a key step towards understanding entanglement in quantum electronic systems. In this Rapid Communication, we introduce the intrinsic two-electron coherence of an electronic source in quantum Hall edge channels and relate it to two-electron wave functions and to current noise in a Hanbury Brown--Twiss interferometer. Inspired by the analogy with photon quantum optics, we propose to measure the intrinsic two-electron coherence of a source using low-frequency current correlation measurements at the output of a Franson interferometer. To illustrate this protocol, we discuss how it can distinguish between a time-bin-entangled pure state and a statistical mixture of time-shifted electron pairs.

DOI
10.1103/physrevb.93.081302

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