Optical Properties of Sm3+ Doped Lithium-Zinc-Alumino Borate Glasses
Lithium-zinc-alumino-fluoroborate glass system based on 15 ZnF2- 10 BaO- 8 Al2O3 – 12 Li2CO3- (55-x) B2O3- xSm2O3 (where x = 0.1, 0.3, 0.5, 0.7 and 1.1mol %) were prepared by melt quench technique. Absorption spectra of these samarium doped glasses showed all possible transitions form the ground state 6H5/2 level to various excited levels. Peak intensity of each absorption band increased with successive addition of samarium ions to the glass matrix. Observed bonding parameter δ was positive signifying the covalent bond between samarium and surrounding ligands. Observed optical band gap was around 3eV, confirming the insulating property of glass. In the luminescence spectra, prominent excitation peak was due to 6H5/2 to 4P3/2 transition at 401 nm. Prominent emission peak was due to4G5/2 to 6H7/2 transition observed at 598 nm. The glass with 0.3 mol % of samarium doping was prominent in emission. From the calculated color co-ordinates, we can conclude that these glasses can be used in orange light emitting diodes.