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arXiv · 1008.1013

Plasmon electron-hole resonance in epitaxial graphene

C. Tegenkamp·H. Pfnuer·T. Langer·J. Baringhaus·H. W. Schumacher
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Abstract

The quasiparticle dynamics of the sheet plasmons in epitaxially grown graphene layers on SiC(0001) have been studied systematically as a function of temperature, intrinsic defects, influence of multilayers and carrier density. The opening of the inter-band loss channel appears as a characteristic upward shift in the plasmon dispersion and a dip in the width of the loss peak, which is explained as a resonance effect in the formation of electron-hole pairs. Despite the existence of strong electronic correlations, the plasmon dispersion can be quantitatively described within the framework of a nearly free electron gas.

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C. Tegenkamp, H. Pfnuer, T. Langer, J. Baringhaus, H. W. Schumacher. 2010-08-05. Plasmon electron-hole resonance in epitaxial graphene. https://arxiv.org/abs/1008.1013

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