Laser light generation in UV-Vis and near-infrared in Sb2O3 glasses

Rezgui, Sayah (2025) Laser light generation in UV-Vis and near-infrared in Sb2O3 glasses. Doctoral thesis, Université de mohamed kheider biskra.

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Abstract

This thesis has systematically unraveled antimony-based glasses' structural, mechanical, and optical properties, focusing on their functionalization through rareearth doping. Integrating compositional engineering, advanced characterization,and spectroscopic analysis has yielded critical insights into designing antimony glasses for tailored applications. Chapter 3 established that the choice of the third oxide (MO) profoundly influences the antimony glass network. XRD and FTIR analyses confirmed the amorphous nature of all compositions, with Sb³⁺ and Sb⁵⁺ coexisting across samples. PbO and ZnO emerged as network formers, reinforcing connectivity through Sb–O– M linkages, whereas BaO acted as a modifier, increasing non-bridging oxygens (NBOs). The phosphorus-containing glass (SNP) exhibited superior mechanical properties (high Young's modulus, E = 70.3 GPa) due to P–O–Sb cross-linking, while borate-containing glasses (SNB) showed the lowest optical band gap (2.45 eV), attributed to enhanced polarizability from BO₃ units. Urbach energy trends revealed that structural disorder is minimized in lead-based glasses (SNPb: 0.1724 eV) and maximized in phosphate systems (SNP: 0.44269 eV), underscoring the inverse relationship between optical basicity and disorder. These results challenge the conventional view that network connectivity alone dictates optical properties, emphasizing instead the role of cationic field strength and orbital interactions. In Chapter 4, the strategic doping of Eu³⁺ and Dy³⁺ unlocked tunable luminescence. Europium-doped glasses demonstrated environment-sensitive emission, with the SNPE composition (30% P₂O₅) achieving the highest asymmetry ratio (9.675) and quantum efficiency due to its distorted Eu³⁺ sites. Judd-Ofelt parameters (Ω₂ = 8.21 × 10⁻²⁰ cm²) confirmed strong covalent Eu–O bonding, while lifetime measurements (1.92 ms) correlated with low non-radiative decay. Codoping with Dy³⁺ in the SNPDE glass enabled dynamic color tuning via single- and two-photon excitation. Under 374 nm excitation, the material emitted cool white light (CCT = 5434 K), shifting to warm white (CCT = 3350 K) at 394 nm. The TPA mechanism, operating in the NIR range (750–1100 nm), facilitated virtual-statemediated energy transfer to Eu³⁺, bypassing traditional upconversion limitations.This nonlinear approach enhanced emission efficiency and demonstrated the potential for depth-resolved imaging in photonic devices. These advancements position antimony glasses as viable alternatives to conventional solid-state lighting and photonics systems. Future work should explore 117 combinatorial doping with other RE³⁺ ions (e.g., Er³⁺, Tm³⁺) and probe the role of nanoscale heterogeneity in energy transfer. Antimony-based materials may soon transition from laboratory curiosities to industrial mainstays by continuing to marry structural precision with optical innovation.

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