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Updated: Nov 12, 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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Electronic spectrum of Kekulé patterned graphene considering second neighbor-interactions
Elías Andrade1, Gerardo G Naumis1, R Carrillo-Bastos2
1Departamento de Sistemas Complejos, Instituto de Fisica, Universidad Nacional Autónoma de México, Apartado Postal 20-364, 01000 Ciudad de México, México.
Summary
Second-neighbor interactions significantly alter Kekulé-Y patterned graphene
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Graphene exhibits unique electronic properties due to its honeycomb lattice structure.
- Kekulé patterns introduce specific bond textures, influencing electronic behavior.
- Understanding interactions beyond nearest neighbors is crucial for precise modeling.
Purpose of the Study:
- To investigate the impact of second-neighbor interactions on Kekulé-Y patterned graphene.
- To develop and validate a low-energy effective Hamiltonian for this system.
- To explore the electronic properties of Kekulé patterned graphene nanoribbons.
Main Methods:
- Tight-binding Hamiltonian formulation.
- Projection of high-energy bands to obtain a low-energy effective Hamiltonian.
- Numerical diagonalization for validation.
- Analysis of graphene nanoribbon properties.
Main Results:
- Second-neighbor interactions induce effective mass and energy shifts in specific bands.
- Degeneracy of conduction bands at the Dirac point is lifted, forming a 'pseudo spin-one Dirac cone'.
- In nanoribbons, these effects are enhanced with decreasing width, and edge states hybridize.
Conclusions:
- Second-neighbor interactions are essential for accurate modeling of Kekulé patterned graphene.
- These interactions significantly modify the electronic band structure, particularly at surfaces and in nanostructures.
- The findings offer insights into designing graphene-based electronic devices.
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