Signatures of surface Majorana modes in the magnetic response of topological superconductors

Luca Chirolli; Francisco Guinea

doi:10.1103/physrevb.99.014506

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arXiv · 1802.09204

Signatures of surface Majorana modes in the magnetic response of topological superconductors

Luca Chirolli·Francisco Guinea

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Abstract

We study the magnetic susceptibility of a two-dimensional cone of Majorana modes localised at the surface of a three-dimensional time-reversal invariant topological superconductor belonging to class DIII. A field parallel to the surface tilts the surface Majorana cone along the supercurrent direction. For fields larger than a critical threshold field $H^*$, $H>H^*$, a transition from type I to type II Dirac cone occurs and a finite current carried by the Majorana modes start to flow, leading to an additional diamagnetic contribution to the surface magnetization. On a curved surface interband transitions are promoted by the Majorana spin connection that couples to the external field, giving rise to a finite frequency magnetic susceptibility.

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Luca Chirolli, Francisco Guinea. 2019-01-08. Signatures of surface Majorana modes in the magnetic response of topological superconductors. https://doi.org/10.1103/physrevb.99.014506

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