Simple approach for high-contrast optical imaging and characterization of graphene-based sheets

Inhwa Jung; Matthew Pelton; Richard Piner; Dmitriy A. Dikin; Sasha Stankovich; Supinda Watcharotone; Martina Hausner; Rodney S. Ruoff

doi:10.1021/nl0714177

arXiv · 0706.0029

Simple approach for high-contrast optical imaging and characterization of graphene-based sheets

Inhwa Jung·Matthew Pelton·Richard Piner·Dmitriy A. Dikin·Sasha Stankovich·Supinda Watcharotone·Martina Hausner·Rodney S. Ruoff

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Abstract

A simple optical method is presented for identifying and measuring the effective optical properties of nanometer-thick, graphene-based materials, based on the use of substrates consisting of a thin dielectric layer on silicon. High contrast between the graphene-based materials and the substrate is obtained by choosing appropriate optical properties and thickness of the dielectric layer. The effective refractive index and optical absorption coefficient of graphene oxide, thermally reduced graphene oxide, and graphene are obtained by comparing the predicted and measured contrasts.

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Inhwa Jung, Matthew Pelton, Richard Piner, Dmitriy A. Dikin, Sasha Stankovich, Supinda Watcharotone, Martina Hausner, Rodney S. Ruoff. 2007-09-05. Simple approach for high-contrast optical imaging and characterization of graphene-based sheets. https://doi.org/10.1021/nl0714177

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