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arXiv · 0706.3907

Coulomb impurity in graphene

Rudro R. Biswas·Subir Sachdev·Dam T. Son
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Abstract

We consider the problem of screening of an electrically charged impurity in a clean graphene sheet. When electron-electron interactions are neglected, the screening charge has a sign opposite to that of the impurity, and is localized near the impurity. Interactions between electrons smear out the induced charge density to give a large-distance tail that follows approximately, but not exactly, an r^{-2} behavior and with a sign which is the same as that of the impurity.

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Rudro R. Biswas, Subir Sachdev, Dam T. Son. 2007-11-29. Coulomb impurity in graphene. https://doi.org/10.1103/physrevb.76.205122

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