Impurity induced broadening of Drude peak in strained graphene

TL;DR

This paper investigates how mechanical strain in graphene enhances impurity-induced scattering, leading to broadening of the Drude peak without changing its weight, through a theoretical model of impurity resonance shifts.

Contribution

It introduces a mechanism linking strain to increased impurity scattering via resonance shifts, using the Lifshitz impurity model to explain experimental observations.

Findings

Strain increases the Drude peak width by shifting impurity resonances.

The Drude weight remains unaffected by strain.

Impurity scattering rate depends on Fermi energy, impurity concentration, and potential.

Abstract

The recent experimental study of the far-infrared transmission spectroscopy of monolayer graphene has shown that the Drude peak width increases by more than $10\%$ per $1\%$ of applied mechanical strain, while the Drude weight remains unchanged. We study the influence of the strain on the resonant impurity scattering. We propose a mechanism of augmentation of the scattering rate due to the shift in the position of resonance. Using the Lifshitz model of substitutional impurities, we investigate changes in the Drude peak weight and width as functions of the Fermi energy, impurity concentration and magnitude of the impurity potential.