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Updated: Feb 8, 2026
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Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors
Published on: January 16, 2020
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Spin-triplet supercurrents in Josephson junctions containing strong ferromagnetic materials
1Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA birge@pa.msu.edu.
Summary
Spin-triplet correlations in ferromagnetic Josephson junctions enable long-range proximity effects, extending superconductivity over tens of nanometers. This contrasts with spin-singlet correlations, which decay rapidly within the ferromagnet.
Area of Science:
- Condensed Matter Physics
- Superconductivity
- Spintronics
Background:
- The proximity effect describes how superconductivity can be induced in a normal metal adjacent to a superconductor.
- Ferromagnetic materials typically suppress the proximity effect due to spin-dependent exchange interactions.
- Theoretical predictions suggest spin-triplet correlations can overcome this suppression.
Purpose of the Study:
- To experimentally investigate the induction and spatial extent of spin-triplet supercurrents in ferromagnetic Josephson junctions.
- To compare the decay length of spin-triplet supercurrents with spin-singlet supercurrents in ferromagnetic systems.
Main Methods:
- Fabrication and characterization of Josephson junctions incorporating strong ferromagnetic materials.
- Measurement of supercurrent transport through these junctions to probe proximity effects.
- Analysis of the spatial decay of spin-singlet and spin-triplet correlations.
Main Results:
- Demonstrated that specific combinations of ferromagnetic materials in Josephson junctions can support spin-triplet supercurrents.
- Observed spin-triplet supercurrents extending over distances of at least several tens of nanometers.
- Showed that spin-singlet supercurrents decay over a much shorter length scale (approximately 1 nm).
Conclusions:
- Spin-triplet pair correlations are crucial for achieving long-range proximity effects in superconductor-ferromagnet hybrid structures.
- Ferromagnetic Josephson junctions offer a viable platform for exploring and utilizing these long-range spin-triplet effects.
Keywords:
Josephson junctionslong-range triplet componentsuperconducting proximity effectsuperconductor–ferromagnet heterostructuresMore Related Videos
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