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arXiv · 1402.5901

Majorana fermions from Shiba states in an antiferromagnetic chain on top of a superconductor

Andreas Heimes·Panagiotis Kotetes·Gerd Schön
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Abstract

We propose a new mechanism for topological superconductivity based on an antiferromagnetically ordered chain of magnetic atoms on the surface of a conventional superconductor. In a weak Zeeman field, a supercurrent in the substrate generates a staggered spin-current, which converts the preexisting topologically-unprotected Shiba states into Majorana fermions (MFs). The two experimental knobs can be finely tuned providing a platform with enhanced functionality for applications. Remarkably, the electronic spin-polarization of the arising edge MF wavefunctions depends solely on the parity of the number of magnetic moments, which can serve as a distinctive signature of the MFs. We introduce the basic concepts within a minimal model and make contact with experiments by a microscopic analysis based on the Shiba states.

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Andreas Heimes, Panagiotis Kotetes, Gerd Schön. 2014-02-24. Majorana fermions from Shiba states in an antiferromagnetic chain on top of a superconductor. https://doi.org/10.1103/physrevb.90.060507

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