Unusual Electronic excitations in ABA trilayer graphene

TL;DR

This paper investigates the unique electronic excitations in ABA trilayer graphene using a tight-binding model combined with the random-phase approximation, revealing diverse plasmon modes and excitation behaviors influenced by doping and layer number.

Contribution

It provides a detailed theoretical analysis of electron-electron interactions and plasmon excitations in ABA trilayer graphene, highlighting the complexity introduced by multiple layers and doping levels.

Findings

Identification of three types of plasmon modes with doping variation

Diverse excitation behaviors influenced by layer number

Theoretical predictions call for high-resolution experimental validation

Abstract

The tight-binding model is closely associated with the modified random-phase approximation to thoroughly explore the electron-electron interactions in trilayer AB-stacked graphene. The intralayer and interlayer atomic/Coulomb interactions dominate the collective and electron-hole excitations. The unusual energy bands are directly reflected in the diverse transferred momentum-frequency phase diagrams. There exist three kinds of plasmon modes during the variation of the doping level, being accompanied with the complicated intraband and interband single-particle excitations. The excitation behaviors are greatly diversified by the number of layers. The theoretical predictions require the high-resolution experimental examinations.