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Published on: August 2, 2019
Ferromagnetic planar Josephson junction with transparent interfaces: a φ junction proposal
D M Heim1, N G Pugach, M Yu Kupriyanov
1Institut für Quantenphysik and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, Ulm, Germany. dennis.heim@uni-ulm.de
Summary
We calculated the current-phase relation for a Josephson junction with a ferromagnetic weak link. This research suggests the junction is a promising candidate for experimental realization of a phi junction.
Area of Science:
- Condensed Matter Physics
- Superconductivity
- Spintronics
Background:
- Josephson junctions are fundamental devices in superconductivity.
- Ferromagnetic weak links introduce unique quantum phenomena.
- Understanding the current-phase relation is crucial for device applications.
Purpose of the Study:
- To calculate the current-phase relation of a specific Josephson junction geometry.
- To investigate the influence of a ferromagnetic weak link on superconducting properties.
- To assess the potential for experimental realization of a phi junction.
Main Methods:
- Theoretical calculation of the current-phase relation.
- Modeling a planar Josephson junction with a ferromagnetic weak link on a normal metal film.
- Assuming transparent superconductor-ferromagnet interfaces for optimal coupling.
Main Results:
- The current-phase relation was successfully calculated.
- Transparent interfaces ensure strong interlayer coupling.
- Superconducting correlations are minimally suppressed in the ferromagnetic layer.
Conclusions:
- The studied Josephson junction is a viable candidate for experimental phi junction realization.
- The theoretical framework provides insights into the behavior of such hybrid devices.
- This work paves the way for novel superconducting spintronic applications.
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