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arXiv · 1210.0076

Cyrstal field splitting and optical band gap of hexagonal LuFeO$_3$ films

Wenbin Wang·Hongwei Wang·Xiaoying Xu·Leyi Zhu·Lixin He·Elizabeth Wills·Xuemei Cheng·David J. Keavney·Jian Shen·Xifan Wu·Xiaoshan Xu
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Abstract

Hexagonal LuFeO$_3$ films have been studied using x-ray absorption and optical spectroscopy. The crystal splittings of Fe$^{3+}$ are extracted as $E_{e'}-E_{e"}$=0.7 eV and $E_{a_1'}-E_{e'}$=0.9 eV and a 2.0 eV optical band gap is determined assuming a direct gap. First-principles calculations confirm the experiments that the relative energies of crystal field splitting states do follow $E_{a_1'}>E_{e'}>E_{e"}$ with slightly underestimated values and a band gap of 1.35 eV.

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Wenbin Wang, Hongwei Wang, Xiaoying Xu, Leyi Zhu, Lixin He, Elizabeth Wills, Xuemei Cheng, David J. Keavney, Jian Shen, Xifan Wu, Xiaoshan Xu. 2012-09-29. Cyrstal field splitting and optical band gap of hexagonal LuFeO$_3$ films. https://doi.org/10.1063/1.4771601

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