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arXiv · 0903.2196

Electrically detected interferometry of Majorana fermions in a topological insulator

A. R. Akhmerov·Johan Nilsson·C. W. J. Beenakker
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Abstract

We show how a chiral Dirac fermion (a massless electron or hole) can be converted into a pair of neutral chiral Majorana fermions (a particle equal to its own antiparticle). These two types of fermions exist on the metallic surface of a topological insulator, respectively, at a magnetic domain wall and at a magnet-superconductor interface. Interferometry of Majorana fermions is a key operation in topological quantum computation, but the detection is problematic since these particles have no charge. The Dirac-Majorana converter enables electrical detection of the interferometric signal.

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A. R. Akhmerov, Johan Nilsson, C. W. J. Beenakker. 2009-03-12. Electrically detected interferometry of Majorana fermions in a topological insulator. https://doi.org/10.1103/physrevlett.102.216404

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