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Optical contrast and refractive index of natural van der Waals heterostructure nanosheets of franckeite.

ABSTRACT: We study mechanically exfoliated nanosheets of franckeite by quantitative optical microscopy. The analysis of transmission-mode and epi-illumination-mode optical microscopy images provides a rapid method to estimate the thickness of the exfoliated flakes at first glance. A quantitative analysis of the optical contrast spectra by means of micro-reflectance allows one to determine the refractive index of franckeite over a broad range of the visible spectrum through a fit of the acquired spectra to a model based on the Fresnel law.

SUBMITTER: Gant P

PROVIDER: S-EPMC5687002 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Optical contrast and refractive index of natural van der Waals heterostructure nanosheets of franckeite.

Gant Patricia P Ghasemi Foad F Maeso David D Munuera Carmen C López-Elvira Elena E Frisenda Riccardo R De Lara David Pérez DP Rubio-Bollinger Gabino G Garcia-Hernandez Mar M Castellanos-Gomez Andres A

Beilstein journal of nanotechnology 20171108

We study mechanically exfoliated nanosheets of franckeite by quantitative optical microscopy. The analysis of transmission-mode and epi-illumination-mode optical microscopy images provides a rapid method to estimate the thickness of the exfoliated flakes at first glance. A quantitative analysis of the optical contrast spectra by means of micro-reflectance allows one to determine the refractive index of franckeite over a broad range of the visible spectrum through a fit of the acquired spectra to ...[more]

PMID: 29181292

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