Tunable proximity effects and topological superconductivity in ferromagnetic hybrid nanowires

Hybrid semiconducting nanowire devices combining epitaxial superconductor and ferromagnetic insulator layers have been recently explored experimentally as an alternative platform for topological superconductivity at zero applied magnetic field. In this proof-of-principle work we show that the topolo...

Descripción completa

Detalles Bibliográficos
Autores: Díaz Escribano, Samuel, Prada, Elsa, Oreg, Yuval, Levy-Yeyati Mizrahi, Alfredo
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/705061
Acceso en línea:http://hdl.handle.net/10486/705061
https://dx.doi.org/10.1103/PhysRevB.104.L041404
Access Level:acceso abierto
Palabra clave:Applied Magnetic Fields
Electrostatic Environments
Ferromagnetic Insulator
Geometrical Constraints
Proof of Principles
Self-Consistent Mean Field
Semiconducting Nanowires
Superconducting Proximity
Física
Descripción
Sumario:Hybrid semiconducting nanowire devices combining epitaxial superconductor and ferromagnetic insulator layers have been recently explored experimentally as an alternative platform for topological superconductivity at zero applied magnetic field. In this proof-of-principle work we show that the topological regime can be reached in actual devices depending on some geometrical constraints. To this end, we perform numerical simulations of InAs wires in which we explicitly include the superconducting Al and magnetic EuS shells, as well as the interaction with the electrostatic environment at a self-consistent mean-field level. Our calculations show that both the magnetic and the superconducting proximity effects on the nanowire can be tuned by nearby gates thanks to their ability to move the wavefunction across the wire section. We find that the topological phase is achieved in significant portions of the phase diagram only in configurations where the Al and EuS layers overlap on some wire facet, due to the rather local direct induced spin polarization and the appearance of an extra indirect exchange field through the superconductor. While of obvious relevance for the explanation of recent experiments, tunable proximity effects are of interest in the broader field of superconducting spintronics