Year: 2026
Type: preprint
Abstract: Near-ideal, field-free superconducting diode behavior is demonstrated in room-temperature-grown Mo$_2$N/FePt bilayers. The response is consistent with remanent FePt stripe domains producing polarity-dependent thresholds for flux entry and vortex motion. Micromagnetic simulations reveal a periodic stray-field modulation across the stripes and asymmetric field enhancement near their ends at the bridge edges. One current polarity remains nearly dissipationless up to a sizable fraction of the estimated depairing current, whereas the opposite polarity develops dissipation at much lower current, yielding diode efficiencies up to approximately 85% in the thinner bilayer. The nonreciprocity can be continuously tuned by the in-plane magnetic preparation angle and reversibly switched by reverse-field excursions through the hysteretic reversal of the FePt layer. These results support edge-controlled flux entry and vortex motion as a route to high-efficiency superconducting diodes.
Source: arXiv (Cornell University)
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7221816101