Analysis of energy transfer based emission spectra of (Sm3+, Dy3+): Li2O-LiF-B2O3-CdO glasses

The present paper brings out the results concerning the preparation and optical properties of Sm3+ and Dy3+ each ion separately in four different concentrations (0.1, 0.5, 1.0 and 1.5 mol%) and also together doped (1 mol% Dy3++x mol% Sm3+): Li2O-LiF-B2O3-CdO (where x=0.1, 0.5, 1.0 and 1.5 mol%) glasses by a melt quenching method. Sm3+ doped base glasses have displayed an intense orange emission at 602 nm (4G5/2→6H7/2) with an excitation at 403 nm and Dy3+ doped glasses have shown two emissions located at 486 nm (4F9/2→6H15/2; blue) and 577 nm (4F9/2→6H13/2; yellow) with λexci=387 nm. The co-doped (Dy3++Sm3+) lithium fluoro-boro cadmium glasses have been excited with an excitation at 387 nm of Dy3+ which has resulted in with a significant reduction in Dy3+ emission, at the same time there exists an increase in the reddish-orange emission of Sm3+ due to an energy transfer from Dy3+ to Sm3+. The non-radiative energy transfer from Dy3+ to Sm3+ is governed by dipole-quadrupole interactions as is explained in terms of their emission spectra, donor lifetime, energy level diagram and energy transfer characteristic factors.