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arXiv · 1808.02484

Plasmon-pole approximation for many-body-effects in extrinsic graphene

E. H. Hwang·Robert E. Throckmorton·S. Das Sarma
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Abstract

We develop the plasmon-pole approximation (PPA) theory for calculating the carrier self-energy of extrinsic graphene as a function of doping density within analytical approximations to the $GW$ random phase approximation ($GW$-RPA). Our calculated self-energy shows excellent quantitative agreement with the corresponding full $GW$-RPA calculation results in spite of the simplicity of the PPA, establishing the general validity of the plasmon-pole approximation scheme. We also provide a comparison between the PPA and the hydrodynamic approximation in graphene, and comment on the experimental implications of our findings.

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E. H. Hwang, Robert E. Throckmorton, S. Das Sarma. 2018-08-07. Plasmon-pole approximation for many-body-effects in extrinsic graphene. https://doi.org/10.1103/physrevb.98.195140

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