Local density of states subject to finite impurity concentration in graphene

TL;DR

This paper investigates how the local density of states in graphene changes with impurity concentration, identifying a critical point where spectral features transform significantly, affecting both the electron spectrum and impurity subsystem.

Contribution

It introduces the concept of a critical impurity concentration in graphene where local density of states behavior and spectral features undergo a fundamental change.

Findings

Identification of a characteristic impurity concentration in graphene

Disappearance of impurity-induced features at high concentrations

Spectral transformation of the impurity subsystem

Abstract

It is demonstrated that there is a characteristic impurity concentration, at which variation with concentration and overall appearance of the local density of states at the impurity site in graphene are changing their behavior. Features that are prominent in the local density of states for the single impurity are disappearing from it when impurity concentration far exceeds this critical value. The impurity subsystem not only induces the rearrangement of the electron spectrum in graphene, but also undergoes a substantial spectral transformation by itself, which can be observed experimentally.