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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
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Spin-layer locked gapless states in gated bilayer graphene
W Jaskólski1, A Ayuela2,3
1Faculty of Physics, Astronomy and Informatics, Institute of Physics, Nicolaus Copernicus University Grudziadzka 5 87-100 Toruń Poland wj@fizyka.umk.pl.
RSC Advances
|May 11, 2022
Summary
Topological states in bilayer graphene with magnetic defects create spin-polarized currents. These currents flow in a single layer, paving the way for spintronic device applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Bilayer graphene hosts topological states at stacking domain walls.
- These states exhibit spin-degenerate, gapless characteristics enabling one-dimensional currents.
Purpose of the Study:
- Investigate the impact of magnetic defects on topological states in bilayer graphene.
- Determine the spin polarization and localization of currents within these perturbed topological states.
Main Methods:
- Theoretical modeling of magnetic defects (π-vacancies) in bilayer graphene.
- Analysis of the perturbation effects on topological states and spin degeneracy.
Main Results:
- Magnetic defects break spin degeneracy, but one gapless state persists.
- The surviving topological state exhibits significant spin polarization localized in a single layer.
- Spin-polarized currents are confined to one layer within the domain walls.
Conclusions:
- Topologically protected currents in bilayer graphene become spin-polarized and layer-locked due to magnetic defects.
- This layer-specific spin-polarized current offers potential for advanced spintronic applications.
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