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arXiv · 1402.6022

Detection of entanglement by helical Luttinger liquids

Koji Sato·Yaroslav Tserkovnyak
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Abstract

A Cooper-pair or electron-hole splitter is a device capable of spatially separating entangled fermionic quasiparticles into mesoscopic solid-state systems such as quantum dots or quantum wires. We theoretically study such a splitter based on a pair of helical Luttinger liquids, which arise naturally at the edges of a quantum spin Hall insulator. Equipping each helical liquid with a beam splitter, current-current cross correlations can be used to construct a Bell inequality whose violation would indicate nonlocal orbital entanglement of the injected electrons and/or holes. Due to Luttinger-liquid correlations, however, the entanglement is exponentially suppressed at finite temperatures.

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Koji Sato, Yaroslav Tserkovnyak. 2014-02-25. Detection of entanglement by helical Luttinger liquids. https://doi.org/10.1103/physrevb.90.045419

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