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arXiv · 2512.10920

Structural, physical, and Judd-Ofelt analysis of germanium magnesium-telluroborate glass containing different amounts of Tm2O3

A. A. El-Maaref·Kh. S. Shaaban·E. A. Abdel Wahab
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Abstract

Germanium magnesium-telluroborate glasses with the composition 78B2O3-10GeO2-5TeO2-7-x MgO-xTm2O3, x = 0, 0.25, 0.5, 1, and 1.5 mol% were fabricated by using the melt quenching process. With the increase of Tm2O3 concentration, the density values increase from 3.574 to 4.153 g/cm^3, while the molar volume values decrease from 21.145 to 19.445 cm3/mol. Fourier transform infrared analysis supports the existence and conversion of BO3 and BO4. The conversion of BO3 to BO4 would lead to greater bridging oxygens BOs, influencing and reinforcing the glass network. The optical features were studied. The optical band gap decreased by increasing Tm2O3 content in the glass formula, while the index of refraction increased. The parameters take the values between 3.16 eV and 2.31 eV. Other optical and physical constants were determined like optical conductivity, electronegativity, metallization, reflection loss, steepness parameters, and transmission coefficient. Judd-Ofelt theory is used to estimate the optical intensities and line strengths of the present glasses. Radiative lifetimes and branching ratios are evaluated of different manifolds belonging to Tm3+ doped present glasses. The results showed the possibility of potential applications for these materials in the fields of laser development, Light-emitting diodes (LEDs), optical amplification and optoelectronic devices.

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A. A. El-Maaref, Kh. S. Shaaban, E. A. Abdel Wahab. 2026-08-30. Structural, physical, and Judd-Ofelt analysis of germanium magnesium-telluroborate glass containing different amounts of Tm2O3. https://arxiv.org/abs/2512.10920

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