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arXiv · 1203.2643

Mutation of Andreev into Majorana bound states in long NS and SNS junctions

D. Chevallier·D. Sticlet·P. Simon·C. Bena
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Abstract

We study one-dimensional topological SN and SNS long junctions obtained by placing a topological insulating nanowire in the proximity of either one or two SC finite-size leads. Using the Majorana Polarization order parameter (MP) introduced in Phys. Rev. Lett. 108, 096802 (2012)(arxiv:1109.5697) we find that the extended Andreev bound states (ABS) of the normal part of the wire acquire a finite MP: for a finite-size SN junction the ABS spectrum exhibits a zero-energy extended state which carries a full Majorana fermion, while the ABS of long SNS junctions with phase difference $\pi$ transform into two zero-energy states carrying two Majorana fermions with the same MP. Given their extended character inside the whole normal link, and not only close to an interface, these Majorana-Andreev states can be directly detected in tunneling spectroscopy experiments.

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D. Chevallier, D. Sticlet, P. Simon, C. Bena. 2012-03-12. Mutation of Andreev into Majorana bound states in long NS and SNS junctions. https://doi.org/10.1103/physrevb.85.235307

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