Majorana Fermion Induced Resonant Andreev Reflection

TLDR

The study reports experimental signatures of Majorana fermion edge states at the interface between a superconductor and a topological insulator. The authors model a lead coupled to Majorana fermions via electron tunneling, inducing resonant Andreev reflections, and analyze current and noise in a two‑lead device. They find that the linear tunneling conductance is 0 for an even number of vortices and 2e²/h for an odd number, with a similar resonance when tunneling into the vortex core zero mode.

Abstract

We describe experimental signatures of Majorana fermion edge states, which form at the interface between a superconductor and the surface of a topological insulator. If a lead couples to the Majorana fermions through electron tunneling, the Majorana fermions induce resonant Andreev reflections from the lead to the grounded superconductor. The linear tunneling conductance is 0 (2e(2)/h) if there is an even (odd) number of vortices in the superconductor. Similar resonance occurs for tunneling into the zero mode in the vortex core. We also study the current and noise of a two-lead device.