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arXiv · 1406.6695

Tilting of the magnetic field in Majorana nanowires: critical angle and zero-energy differential conductance

Stefan Rex·Asle Sudbø
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Abstract

Semiconductor nanowires with strong spin-orbit coupling and proximity-induced s-wave superconductivity in an external magnetic field have been the most promising settings for approaches towards experimental evidence of topological Majorana zero-modes. We investigate the effect of tilting the magnetic field relative to the spin-orbit coupling direction in a simple continuum model and provide an analytical derivation of the critical angle, at which the topological states disappear. We also obtain the differential conductance characteristic of a junction with a normal wire for different tilting angles and propose the qualitative change of the dependence of the zero-energy differential conductance on the tunnel barrier strength at the critical angle as a new criterion for establishing the topological nature of the observed signal.

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Stefan Rex, Asle Sudbø. 2014-06-25. Tilting of the magnetic field in Majorana nanowires: critical angle and zero-energy differential conductance. https://doi.org/10.1103/physrevb.90.115429

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