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

  title={Probing the helical edge states of a topological insulator by Cooper-pair injection},
  author={Pierre Adroguer and Charles Grenier and David Carpentier and J Cayssol and P Degiovanni and Edmond Orignac},
  journal={Physical Review B},
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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