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arXiv · 1303.0131

Effect of Dynamical Screening on Single Particle Spectral Features of Uniaxially Strained Graphene: Tuning the Plasmaron Ring

Abstract

Electronic screening renormalizes the linear bands of graphene and in the vicinity of the Dirac point, creates a diamond shaped structure in the quasiparticle spectral density. This is a result of electron-plasmon scattering processes which produce a finite momentum feature referred to as the `plasmaron ring'. In this work we explore the effects of uniaxial strain on these spectral features with the aim of understanding how strain modifies correlations. We derive and calculate the spectral density to the G$_0$W-RPA level which allows us to identify the dispersive behaviour of the diamond geometry, and thus electron-plasmon scattering, for variation in electron-electron coupling strength and magnitude of applied strain. We find that the application of strain changes the geometry (in momentum) of the electron-plasmon scattering and that renormalizations beyond simple geometrical scalings further enhance this effect. These results suggest that the properties of the plasmaron ring can be tuned through the application of uniaxial strain, effectively producing a larger fine structure constant without the need to change the sample substrate.

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J. P. F. LeBlanc, J. P. Carbotte. 2013-03-01. Effect of Dynamical Screening on Single Particle Spectral Features of Uniaxially Strained Graphene: Tuning the Plasmaron Ring. https://doi.org/10.1103/physrevb.87.205407

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