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arXiv · 2511.17114

Effect of temperature and excitation power on down-conversion process in Tb3+/Yb3+-activated silica-hafnia glass-ceramic films

S. E. Amrani·M. Sun·S. Valdueza-Felip·F. B. Naranjo·M. R. Britel·M. Ferrari·A. Bouajaj
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Abstract

Transparent glass ceramics, when activated by rare earth ions, are excellent photonic materials. Regarding photonic glass-ceramics based on silicates, hafnia and silica in a binary system has proved to be an excellent matrix to incorporate rare earth ions in the hafnia nanocrystals, resulting in important luminescence enhancement and, consequently, allowing a large spectrum of critical applications. Here we will focus on the downconversion mechanism driven by the couple Tb3+/Yb3+, largely exploited in photovoltaic systems. The research presented here has been performed on 70SiO2-30HfO2 silica-hafnia glass-ceramic films activated with 19 % rare earth ions: [Tb + Yb]/[Si + Hf] = 19 %. Two main results will be discussed: (a) the intensity and the broadening of the Yb3+ emission band at 975 nm were found to be temperature-dependent, as shown in the figure; (b) the energy transfer mechanism Tb3+ >> Yb3+ will be discussed, referring to the mechanisms that have been proposed in the literature. In relation to the latter topic, the power dependence spectra for the luminescence of Yb3+: 2F5/2 >> 2F7/2 will be discussed.

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S. E. Amrani, M. Sun, S. Valdueza-Felip, F. B. Naranjo, M. R. Britel, M. Ferrari, A. Bouajaj. 2025-11-21. Effect of temperature and excitation power on down-conversion process in Tb3+/Yb3+-activated silica-hafnia glass-ceramic films. https://doi.org/10.1016/j.ceramint.2024.06.392

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