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arXiv · 1006.0215

Probing the helical edge states of a topological insulator by Cooper-pair injection

P. Adroguer·C. Grenier·D. Carpentier·J. Cayssol·P. Degiovanni·E. Orignac
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Abstract

We consider the proximity effect between a singlet s-wave superconductor and the edge of a Quantum Spin Hall (QSH) topological insulator. We establish that Andreev reflection at a QSH edge state/superconductor interface is perfect while nonlocal Andreev processes through the superconductor are totally suppressed. We compute the corresponding conductance and noise.

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P. Adroguer, C. Grenier, D. Carpentier, J. Cayssol, P. Degiovanni, E. Orignac. 2010-08-05. Probing the helical edge states of a topological insulator by Cooper-pair injection. https://doi.org/10.1103/physrevb.82.081303

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