Measuring the Complex Optical Conductivity of Graphene by Fabry-Pérot Reflectance Spectroscopy

Behnood G. Ghamsari, Jacob Tosado, Mahito Yamamoto, Michael S. Fuhrer, Steven M. Anlage

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18 Citations (Scopus)


We have experimentally studied the dispersion of optical conductivity in few-layer graphene through reflection spectroscopy at visible wavelengths. A laser scanning microscope (LSM) with a supercontinuum laser source measured the frequency dependence of the reflectance of exfoliated graphene flakes, including monolayer, bilayer and trilayer graphene, loaded on a Si/SiO 2 Fabry-Pérot resonator in the 545-700 nm range. The complex refractive index of few-layer graphene, n-ik, was extracted from the reflectance contrast to the bare substrate. It was found that each few-layer graphene possesses a unique dispersionless optical index. This feature indicates that the optical conductivity does not simply scale with the number of layers, and that inter-layer electrodynamics are significant at visible energies.

Original languageEnglish
Article number34166
Number of pages7
JournalScientific Reports
Publication statusPublished - 29 Sept 2016
Externally publishedYes

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