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Origin of Universal Optical Conductivity and Optical Stacking Sequence Identification in Multilayer Graphene
Published
Author(s)
Hongki Min, Allan H. MacDonald
Abstract
We predict that the optical conductivity of normal graphene multilayers is close to ςuni=(π/2) e2/h per layer over a broad range of frequencies. The origin of this behavior is an emergent chiral symmetry which is present in normal N-layer stacks when small distant neighbor hopping amplitudes are neglected, and implies that ς (ω) =Nςuni in both low and high frequency limits. We discuss the possibility of obtaining useful information about stacking sequences from optical conductivity measurements.
Min, H.
and MacDonald, A.
(2009),
Origin of Universal Optical Conductivity and Optical Stacking Sequence Identification in Multilayer Graphene, Physical Review Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=902107
(Accessed October 8, 2025)