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arXiv · 1111.6280

Electron-hole puddles in the absence of charged impurities

Marco Gibertini·Andrea Tomadin·Francisco Guinea·Mikhail I. Katsnelson·Marco Polini
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Abstract

It is widely believed that carrier-density inhomogeneities ("electron-hole puddles") in single-layer graphene on a substrate like quartz are due to charged impurities located close to the graphene sheet. Here we demonstrate by using a Kohn-Sham-Dirac density-functional scheme that corrugations in a real sample are sufficient to determine electron-hole puddles on length scales that are larger than the spatial resolution of state-of-the-art scanning tunneling microscopy.

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Marco Gibertini, Andrea Tomadin, Francisco Guinea, Mikhail I. Katsnelson, Marco Polini. 2011-11-27. Electron-hole puddles in the absence of charged impurities. https://doi.org/10.1103/physrevb.85.201405

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