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arXiv · 1207.6139

Optical Response of DyN

M. Azeem·B. J. Ruck·Binh Do Le·H. Warring·N. M. Strickland·A. Koo·V. Goian·S. Kamba·H. J. Trodahl
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Abstract

We report measurements of the optical response of polycrystalline DyN thin films. The frequency-dependent complex refractive index in the near IR-visible-near UV was determined by fitting reflection/transmission spectra. In conjunction with resistivity measurements these identify DyN as a semiconductor with 1.2 eV optical gap. When doped by nitrogen vacancies it shows free carrier absorption and a blue-shifted gap associated with the Moss-Burstein effect. The refractive index of 2.0+/-0.1 depends only weakly on energy. Far infrared reflectivity data show a polar phonon of frequency 280 cm-1 and dielectric strength delta epsilon= 20.

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M. Azeem, B. J. Ruck, Binh Do Le, H. Warring, N. M. Strickland, A. Koo, V. Goian, S. Kamba, H. J. Trodahl. 2012-07-25. Optical Response of DyN. https://doi.org/10.1063/1.4807647

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