Physical and luminescence properties of samarium doped oxide and oxyfluoride phosphate glasses

The research work emphasizes on physical and luminescence properties of oxide and oxyfluoride phosphate glasses and discusses the energy transfer between Gd ³⁺ and Sm ³⁺ ions. Lithium gadolinium oxide and oxy-fluoride phosphate glasses doped with Sm ³⁺ ions were prepared by conventional melt quenching technique. Subsequently the physical and luminescence properties were investigated systematically to understand their behavior. The density of the prepared glass samples show high in oxide glasses as compared to oxy-fluoride glasses, and the density of both glass samples increase with increase in the Sm ₂ O ₃ concentrations. In total, ten signature Sm ³⁺ ion peaks were observed in the UV-Vis-NIR absorption spectra. In photoluminescence spectra the oxy-fluoride glass samples show higher excitation and emissions intensity than oxide glasses. The emission intensity increases up to 1mol% concentration of Sm ³⁺ ions and then decreases due to non-radiative energy transfers. The same is observed in case of radioluminescence emission spectra. The calculated J-O intensity parameters show Ω ₂ > Ω ₄ > Ω ₆ trend. From Judd-Ofelt analysis, these glasses exhibit high potential for using as laser host medium. The life time recorded at the excitation and emission wavelength 401 nm and 598 nm respectively and it is observed that the life time decreases with increase in the Sm ³⁺ ions concentration. The CIE coordinates positioned in the orange region of CIE diagram. The properties evaluated in the present work indicate that these glasses can be a good candidate of orange LEDs applications.