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arXiv · 1810.05215

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

Patricia Gant·Foad Ghasemi·David Maeso·Carmen Munuera·Elena López-Elvira·Riccardo Frisenda·David Pérez De Lara·Gabino Rubio-Bollinger·Mar Garcia-Hernandez·Andres Castellanos-Gomez
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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 in a broad range of the visible spectrum through a fit of the acquired spectra to a Fresnel law based model.

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Patricia Gant, Foad Ghasemi, David Maeso, Carmen Munuera, Elena López-Elvira, Riccardo Frisenda, David Pérez De Lara, Gabino Rubio-Bollinger, Mar Garcia-Hernandez, Andres Castellanos-Gomez. 2018-10-11. Optical contrast and refractive index of natural van der Waals heterostructure nanosheets of franckeite. https://doi.org/10.3762/bjnano.8.235

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