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Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
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Spin-controlled superconductivity and tunable triplet correlations in graphene nanostructures
Klaus Halterman1, Oriol T Valls, Mohammad Alidoust
1Michelson Lab, Physics Division, Naval Air Warfare Center, China Lake, California 93555, USA. klaus.halterman@navy.mil
Physical Review Letters
|August 13, 2013
Summary
We demonstrate a graphene switch controlling superconductivity using spin. This graphene-based device enables tunable on/off switching of superconductivity and spin-triplet correlations.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Phenomena
Background:
- Graphene's unique electronic properties make it a candidate for novel electronic devices.
- Proximity effects in ferromagnet/superconductor heterostructures are crucial for spintronics and quantum computing.
Purpose of the Study:
- To investigate spin switching phenomena in graphene ferromagnet/superconductor/ferromagnet (F/S/F) nanostructures.
- To explore the possibility of creating a tunable superconducting switch and a spin-triplet valve based on graphene.
Main Methods:
- Utilized a microscopic self-consistent Dirac Bogoliubov-de Gennes formalism.
- Analyzed proximity effects in F/S/F nanostructures.
Main Results:
- Demonstrated experimentally accessible spin switching phenomena by tuning the Fermi level (μF) or exchange field orientation angle (θ).
- Showcased on/off switching of superconductivity by varying θ or μF, realizing a spin-controlled superconducting graphene switch.
- Achieved control over induced equal-spin triplet correlations in the superconductor via μF tuning, creating a graphene-based 2D spin-triplet valve.
Conclusions:
- Graphene F/S/F nanostructures offer a platform for novel spintronic and superconducting devices.
- Tunable control over superconductivity and spin correlations in graphene opens avenues for advanced quantum technologies.
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