Majorana fermions in chains of magnetic atoms on a superconductor

TL;DR

This paper proposes a practical method to realize and detect Majorana fermions in magnetic atom chains on superconductors, highlighting their tunability and detectability via scanning tunneling microscopy.

Contribution

It introduces a simple scheme for creating Majorana fermions in magnetic atom chains on superconductors, with model calculations demonstrating tunability and detection methods.

Findings

Chains can be tuned between trivial and topological states.

Majorana bound states can form in short chains of tens of atoms.

Scanning tunneling microscopy can detect Majorana end states.

Abstract

We propose an easy-to-build easy-to-detect scheme for realizing Majorana fermions at the ends of a chain of magnetic atoms on the surface of a superconductor. Model calculations show that such chains can be easily tuned between trivial and topological ground state. In the latter, spatial resolved spectroscopy can be used to probe the Majorana fermion end states. Decoupled Majorana bound states can form even in short magnetic chains consisting of only tens of atoms. We propose scanning tunneling microscopy as the ideal technique to fabricate such systems and probe their topological properties.