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arXiv · 2310.20276

Temperature dependent optical properties of $\varepsilon$-Ga$_2$O$_3$ thin films

T. Makino·S. Yusa·D. Oka·T. Fukumura
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Abstract

We determined the complex dielectric functions of $\varepsilon$-Ga$_2$O$_3$ using optical transmittance and reflectance spectroscopies at temperatures from 10 K to room temperature. The measured dielectric-function spectra reveal distinct structures at a bandgap energy. We fitted a model dielectric function based on the electronic energy-band structure to these experimental data. We analyzed the temperature dependence of the band-gap with a model based on phonon dispersion effects. One could explain it in terms of phonon-related parameters such as the optical phonon temperature. We compare phonon-related properties of $\varepsilon$-Ga$_2$O$_3$ with those of a large variety of element and binary semiconductors.

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T. Makino, S. Yusa, D. Oka, T. Fukumura. 2023-10-31. Temperature dependent optical properties of $\varepsilon$-Ga$_2$O$_3$ thin films. https://doi.org/10.35848/1347-4065%2Fac2215

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