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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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Tunable Fermi level and hedgehog spin texture in gapped graphene
A Varykhalov1, J Sánchez-Barriga1, D Marchenko2
1Helmholtz-Zentrum Berlin für Materialien und Energie, Elektronenspeicherring BESSY II, Albert-Einstein-Straße 15, 12489 Berlin, Germany.
Nature Communications
|July 28, 2015
Summary
Gold-intercalated graphene on iron creates a large bandgap with an out-of-plane spin texture. This spin reorientation is tunable, offering potential for electrical gating in spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Graphene exhibits spin-orbit interactions leading to in-plane Rashba spin textures.
- Controlling spin textures in graphene is crucial for spintronic applications.
Purpose of the Study:
- Investigate spin texture and bandgap formation in Au-intercalated graphene on Fe(110).
- Explore the tunability of spin properties for potential device applications.
Main Methods:
- Utilized angle-resolved photoemission spectroscopy (ARPES) to probe electronic structure.
- Analyzed the impact of gold intercalation and substrate symmetry on graphene's spin properties.
Main Results:
- Observed a significant bandgap (∼230 meV) with an out-of-plane hedgehog spin reorientation.
- Identified a giant Rashba effect (∼70 meV splitting) and broken graphene symmetry.
- Demonstrated tunable Fermi level positioning within the bandgap via Au concentration.
Conclusions:
- Au-intercalated graphene on Fe(110) exhibits a unique out-of-plane spin texture and tunable bandgap.
- The observed phenomena are attributed to a giant Rashba effect and substrate-induced symmetry breaking.
- This system serves as a model for electrical gating of spin in spintronic devices.
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