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arXiv · 0903.2163

Origin of Universal Optical Conductivity and Optical Stacking Sequence Identification in Multilayer Graphene

Hongki Min·A. H. MacDonald
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Abstract

We show that the origin of the universal optical conductivity in a normal $N$-layer graphene multilayer is an emergent chiral symmetry which guarantees that $σ(ω)=Nσ_{uni}$ in both low and high frequency limits. [$σ_{uni}=(π/2) e^2/h$]. We use this physics to relate intermediate frequency conductivity trends to qualitative characteristics of the multilayer stacking sequence.

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Hongki Min, A. H. MacDonald. 2009-08-06. Origin of Universal Optical Conductivity and Optical Stacking Sequence Identification in Multilayer Graphene. https://doi.org/10.1103/physrevlett.103.067402

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