Superconducting proximity effect and Majorana fermions at the surface of a topological insulator

Liang Fu; C. L. Kane

doi:10.1103/physrevlett.100.096407

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arXiv · 0707.1692

Superconducting proximity effect and Majorana fermions at the surface of a topological insulator

Liang Fu·C. L. Kane

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Abstract

We study the proximity effect between an s-wave superconductor and the surface states of a strong topological insulator. The resulting two dimensional state resembles a spinless p_x+ip_y superconductor, but does not break time reversal symmetry. This state supports Majorana bound states at vortices. We show that linear junctions between superconductors mediated by the topological insulator form a non chiral 1 dimensional wire for Majorana fermions, and that circuits formed from these junctions provide a method for creating, manipulating and fusing Majorana bound states.

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Liang Fu, C. L. Kane. 2008-04-28. Superconducting proximity effect and Majorana fermions at the surface of a topological insulator. https://doi.org/10.1103/physrevlett.100.096407

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