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Odd triplet pairing in clean superconductor/ferromagnet heterostructures
Klaus Halterman1, Paul H Barsic, Oriol T Valls
1Physics and Computational Sciences, Research and Engineering Sciences Department, Naval Air Warfare Center, China Lake, California 93555, USA. klaus.halterman@navy.mil
Physical Review Letters
|October 13, 2007
Summary
Triplet correlations are induced in ferromagnet/superconductor nanojunctions. These correlations, odd in time, are long-ranged and depend on magnetization alignment.
Area of Science:
- Condensed matter physics
- Spintronics
- Superconductivity
Background:
- Ferromagnet/superconductor heterostructures are crucial for spintronic devices.
- Understanding triplet pairing correlations is key to novel superconducting functionalities.
Purpose of the Study:
- Investigate triplet pairing correlations in clean ferromagnet (F)/superconductor (S) nanojunctions.
- Analyze the influence of magnetization angle on these correlations.
- Determine the spatial and temporal behavior of induced triplet correlations.
Main Methods:
- Fully self-consistent solution of Bogoliubov-de Gennes equations.
- Modeling of ferromagnet-superconductor-ferromagnet (FSF) trilayers.
- Analysis of s-wave superconducting properties.
Main Results:
- Triplet correlations, odd in time, are induced in both S and F layers in the clean limit.
- These correlations exhibit long-range behavior in both S and F layers at specific timescales.
- The zero-temperature condensation energy is minimized when magnetizations are antiparallel.
Conclusions:
- Triplet correlations are robustly induced in F/S nanojunctions, contrary to some prior theories.
- The observed long-range nature and dependence on magnetization angle offer pathways for controlling superconducting states.
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