Publication

Abstract : Here, we report highly polarizable host-enabled efficient Dy3+ incorporation and strong luminescence in Dy3+-doped Li2O + CaO + Bi2O3 + B2O3 (LCBB) glasses synthesised via melt quenching, as revealed by systematic correlations between structural, optical, and luminescence attributes. X-ray diffraction confirms the amorphous nature of the prepared glasses, while the density increases systematically with increasing Dy3+ concentration. Photoluminescence studies under UV excitation (349, 365, and 385 nm) reveal an intense and tuneable near-white emission arising from the characteristic Dy3+-transitions (blue: 4F9/2 ➔ 6H15/2; dominant yellow: 4F9/2 ➔ 6H13/2). Among all compositions, the 0.75 mol% Dy3+-doped LCBB glass exhibits warm, near-white emission with a high emission power (∼24.8 × 104 W/nm at 385 nm) and the lowest CCT (4602 K). The Judd-Ofelt analysis indicates that the highly polarizable LCBB host stabilizes an asymmetric and covalent local environment around Dy3+-O2−, leading to favourable radiative transition probabilities. The fluorescence lifetime analysis reveals single-exponential decay behaviour with a concentration-dependent reduction in lifetime, indicating the onset of quenching by Dy3+-Dy3+ interactions at higher dopant levels. Overall, the Dy3+-doped LCBB glass demonstrates strong potential for warm near-white-emitting photonic applications.