Steric Interference in Bilayer Graphene with Point Dislocations.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Materials Science

Background:

• Bilayer graphene exhibits unique electronic and mechanical properties.
• Understanding defect behavior, such as dislocations, is crucial for its applications.
• Accurate interatomic potentials are essential for simulating graphene.

Purpose of the Study:

• To investigate steric interference in bilayer graphene with offset point dislocations.
• To validate the Long-Range Carbon Bond-Order Potential (LCBOP) for graphene simulations.
• To analyze dislocation configurations and their interactions.

Main Methods:

• Utilized Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS).
• Employed the Long-Range Carbon Bond-Order Potential (LCBOP) developed by Los et al.
• Validated the potential through phonon dispersion curves and harmonic response.
• Simulated dislocation dipoles and quadrupoles in monolayer and bilayer graphene.

Main Results:

• The LCBOP potential was validated against experimental data and other potentials.
• Strong steric interference was observed in bilayer graphene with offset dislocations.
• Out-of-plane displacements were identified as the cause of steric interactions.
• Dislocation quadrupole configurations showed significant steric effects.

Conclusions:

• The LCBOP potential is suitable for simulating defect interactions in graphene.
• Offset dislocations in bilayer graphene experience substantial steric hindrance.
• Out-of-plane atomic movements are critical in understanding these interactions.
• Findings provide insights into the mechanical behavior of defective graphene structures.