| Popis: |
The present paper brings out the results concerning the preparation and optical properties of Sm 3+ and Dy 3+ each ion separately in four different concentrations (0.1, 0.5, 1.0 and 1.5 mol%) and also together doped (1 mol% Dy 3+ + x mol% Sm 3+ ): Li 2 O–LiF–B 2 O 3 –CdO (where x =0.1, 0.5, 1.0 and 1.5 mol%) glasses by a melt quenching method. Sm 3+ doped base glasses have displayed an intense orange emission at 602 nm ( 4 G 5/2 → 6 H 7/2 ) with an excitation at 403 nm and Dy 3+ doped glasses have shown two emissions located at 486 nm ( 4 F 9/2 → 6 H 15/2 ; blue ) and 577 nm ( 4 F 9/2 → 6 H 13/2 ; yellow ) with λ exci =387 nm. The co-doped (Dy 3+ +Sm 3+ ) lithium fluoro-boro cadmium glasses have been excited with an excitation at 387 nm of Dy 3+ which has resulted in with a significant reduction in Dy 3+ emission, at the same time there exists an increase in the reddish-orange emission of Sm 3+ due to an energy transfer from Dy 3+ to Sm 3+ . The non-radiative energy transfer from Dy 3+ to Sm 3+ 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. |
Full Text from ScienceDirect