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arXiv · 2303.16261

Conductance asymmetry in proximitized magnetic topological insulator junctions with Majorana modes

Daniele Di Miceli·Eduárd Zsurka·Julian Legendre·Kristof Moors·Thomas Schmidt·Llorenç Serra
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Abstract

We theoretically discuss electronic transport via Majorana states in magnetic topological insulator-superconductor junctions with an asymmetric split of the applied bias voltage. We study normal-superconductor-normal (NSN) junctions made of narrow (wire-like) or wide (film-like) magnetic topological insulator slabs with a central proximitized superconducting sector. The occurrence of charge non-conserving Andreev processes entails a nonzero conductance related to an electric current flowing to ground from the proximitized sector of the NSN junction. We show that topologically-protected Majorana modes require an antisymmetry of this conductance with respect to the point of equally split bias voltage across the junction.

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Daniele Di Miceli, Eduárd Zsurka, Julian Legendre, Kristof Moors, Thomas Schmidt, Llorenç Serra. 2023-03-28. Conductance asymmetry in proximitized magnetic topological insulator junctions with Majorana modes. https://doi.org/10.1103/physrevb.108.035424

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