Single-crystalline hexagonal GaN (α-GaN) film on (0001) sapphire substrate. Room temperature.
1) T. Kawashima, H. Yoshikawa, S. Adachi. Optical properties of hexagonal GaN, J. Appl. Phys. 82, 3528-3535 (1997)
2) S. Logothetidis, J. Petalas, M. Cardona, T. D. Moustakas. Optical properties and temperature dependence of the interband transitions of cubic and hexagonal GaN, Phys. Rev. B 50, 18017-18029 (1994)
* Authors of Ref. 1 provide a simplified model of the interband transitions (MDF) based on their experimental data combined with experimental data from Ref. 2.
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