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Updated: Aug 29, 2025
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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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Strong Coupling Superconductivity in Ca-Intercalated Bilayer Graphene on SiC.
Xutao Wang1, Ningning Liu1, Yanfu Wu1
1Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
Nano Letters
|September 6, 2022
Summary
Researchers observed superconductivity in calcium-intercalated bilayer graphene, a material with potential for strong correlation effects. This discovery offers insights into the mechanisms driving superconductivity in doped graphene systems.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Superconductivity
Background:
- Metal-intercalated bilayer graphene exhibits flat bands near the Fermi energy, suggesting strong correlation effects.
- These properties make it a promising candidate for novel phenomena like superconductivity.
Purpose of the Study:
- To experimentally investigate superconductivity in Ca-intercalated bilayer graphene.
- To characterize the superconducting properties and understand the underlying mechanisms.
Main Methods:
- Utilized a self-developed multifunctional scanning tunneling microscope.
- Measured superconducting energy gap and diamagnetic response.
- Analyzed penetration depth variations with temperature and magnetic field.
Main Results:
- Observed a superconducting energy gap and diamagnetic response in Ca-intercalated bilayer graphene.
- Determined a critical temperature (Tc) of 8.83 K.
- Revealed a high gap ratio (2Δ/kBTc ≈ 5.0), indicative of strong coupling superconductivity.
- Characterized the material as an isotropic s-wave superconductor based on penetration depth analysis.
Conclusions:
- Ca-intercalated bilayer graphene exhibits strong coupling superconductivity.
- The findings provide critical experimental evidence for superconductivity in carrier-doped graphene.
- This study advances the understanding of superconductivity mechanisms in advanced graphene materials.
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