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arXiv · 1610.04671

Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2

Yilei Li·Alexey Chernikov·Xian Zhang·Albert Rigosi·Heather M. Hill·Arend M. van der Zande·Daniel A. Chenet·En-Min Shih·James Hone·Tony F. Heinz
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Abstract

We report a determination of the complex in-plane dielectric function of monolayers of four transition metal dichalcogenides: MoS2, MoSe2, WS2 and WSe2, for photon energies from 1.5 - 3 eV. The results were obtained from reflection spectra using a Kramers-Kronig constrained variational analysis. From the dielectric functions, we obtain the absolute absorbance of the monolayers. We also provide a comparison of the dielectric function for the monolayers with the corresponding bulk materials.

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Yilei Li, Alexey Chernikov, Xian Zhang, Albert Rigosi, Heather M. Hill, Arend M. van der Zande, Daniel A. Chenet, En-Min Shih, James Hone, Tony F. Heinz. 2016-10-15. Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2. https://doi.org/10.1103/physrevb.90.205422

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