Large interfacial exchange fields in a thick superconducting film coupled to a spin-filter tunnel barrier
Type
Article
Change log
Authors
Pal, A
Blamire, MG
Abstract
The differential conductance of NbN/GdN/TiN superconductor / ferromagnetic insulator / normal metal junctions, with a thick NbN layer shows a large zero-field voltage offset interpreted as a spin-filtered Zeeman splitting of the NbN density of states (DOS) by an effective exchange field (H₀) from the GdN. The splitting increases linearly with applied field (H_ext) enabling the relative sign of H₀ and H_ext to be determined. We show that the short NbN coherence length concentrates H₀ at the NbN/GdN interface and eliminates any averaging over the GdN domain structure leading to a large zero-field splitting.
Description
Keywords
51 Physical Sciences, 5104 Condensed Matter Physics
Journal Title
Physical Review B - Condensed Matter and Materials Physics
Conference Name
Journal ISSN
1098-0121
1550-235X
1550-235X
Volume Title
92
Publisher
American Physical Society (APS)
Publisher DOI
Sponsorship
This work was supported by the ERC Advanced Investigator Grant (Superspin).