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Optical properties of MgH2 measured in situ in a novel gas cell for ellipsometry/spectrophotometry

J. Isidorsson·I. A. M. E. Giebels·H. Arwin·R. Griessen
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Abstract

The dielectric properties of alpha-MgH2 are investigated in the photon energy range between 1 and 6.5 eV. For this purpose, a novel sample configuration and experimental setup are developed that allow both optical transmission and ellipsometric measurements of a transparent thin film in equilibrium with hydrogen. We show that alpha-MgH2 is a transparent, colour neutral insulator with a band gap of 5.6 +/- 0.1 eV. It has an intrinsic transparency of about 80% over the whole visible spectrum. The dielectric function found in this work confirms very recent band structure calculations using the GW approximation by Alford and Chou [J.A. Alford and M.Y. Chou (unpublished)]. As Pd is used as a cap layer we report also the optical properties of PdHx thin films.

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J. Isidorsson, I. A. M. E. Giebels, H. Arwin, R. Griessen. 2003-05-18. Optical properties of MgH2 measured in situ in a novel gas cell for ellipsometry/spectrophotometry. https://doi.org/10.1103/physrevb.68.115112

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