P2O5–TiO2–CaO glasses as a host for Nd3+, structure and optical properties

Abstract

The system of P2O5–TiO2–CaO was investigated as a proper host for rare-earth ions. Glasses comprising P2O5, TiO2, and CaO were doped with neodymium (0.5, 1, and 1.5 mol%) through melting method at 1350–1400 °C. UV–Vis spectrum showed a rise in the absorbance by increasing the dopant content. The absorbance at the wavelength of 583 nm was 2.4 times higher than the glass containing 0.5 mol% Nd2O3 (G-Nd 0.5). Optical findings also indicated a decline in the emission intensity at all wavelengths. FT-IR and Raman analysis revealed that Nd entered the structure of the phosphate glass as a modifier. The direct Optical band gap energy showed a decline from 3.38 eV in G-Nd0 to 3.33 eV for G-Nd1.5. Nd3+ incorporation led to an increase in the Urbach energy as the highest and lowest Urbach energies were recorded in G-Nd1 (0.017 eV) and G-Nd0 (0.058).