Multimode Friedel oscillations in monolayer and bilayer graphene

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Mechanics

Background:

• Static screening is crucial for understanding electronic properties in 2D materials.
• Friedel oscillations (FOs) are key indicators of screening behavior.
• Graphene's unique electronic structure influences screening mechanisms.

Purpose of the Study:

• To investigate the impact of charged impurities on static screening in monolayer and bilayer graphene.
• To analyze layer-specific responses and Friedel oscillations (FOs) in different graphene stacking configurations.
• To elucidate the distinctions in screening behavior between monolayer and bilayer graphene.

Main Methods:

• Application of the random phase approximation (RPA) for theoretical analysis.
• Self-consistent field interactions were considered for bilayer graphene.
• Analysis of induced charge density and oscillatory patterns.

Main Results:

• Monolayer graphene exhibits beating Friedel oscillations (FOs) in both inter-valley and intra-valley channels.
• AA-stacked bilayer graphene shows distinct metallic screening with unique oscillatory patterns.
• AB-stacked bilayer graphene reveals layer-specific responses in parabolic bands and multimode FOs.

Conclusions:

• The study provides a comprehensive understanding of layer-dependent static screening in graphene.
• Distinctions in Friedel oscillations (FOs) between monolayer and bilayer graphene are clarified.
• Findings offer insights into static Coulomb scattering effects in multilayer graphene systems.