Work

Quantum-geometric spin and charge Josephson diode effects

Year: 2025

Type: article

Abstract: We present a general mechanism for large charge and spin Josephson diode effects in strongly spin-polarized superconductor-ferromagnet hybrid structures with a noncoplanar spin texture, formulated in terms of quantum-geometric phases. We present necessary conditions for this effect to occur, and show numerical results for disordered materials relevant to applications. We calculate Josephson diode efficiencies for both charge and spin diodes and show that a spin-diode efficiency of 100% can be reached. Finally, we present a SQUID device that can switch between nearly pure spin-up and spin-down equal-spin supercurrents across the ferromagnet by reversing the flux. These findings establish functionalities that are absent in coplanar spin textures.

Source: Physical review. B./Physical review. B

DOI: 10.1103/nb38-v1jq

Authors: Niklas L. Schulz, Danilo Nikolić, Matthias Eschrig

Institution: Universität Greifswald

Language: English

Topic: Physics of Superconductivity and Magnetism

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funders: Deutsche Forschungsgemeinschaft, Universität Greifswald

Award: Geometrische Phasen und SpinPumpen in Supraleitenden SpintronikBauelementen