Popis: |
The mechanism of non-radiative energy transfer between Tb3+ and Nd3+ ions in fluorophosphate glass has been analyzed with the Forster-Dexter theory. Several/transfer parameters such as the transfer probability, transfer efficiency, critical transfer distance, and critical concentration have been evaluated by fitting the experimental fluorescence spectrum of those ions with that theory. The recorded emission spectrum of Tb3+ with different Nd3+ ion concentrations shows that the transfer process from the 5D4 state of Tb3+ to the 4G5/2 state of Nd3+ is driven predominantly by a dipole-dipole interaction. The effect of this energy transfer is to considerably enhance the optical gain of the 4F3/2 to 4I11/2 emission band of Nd3+ ions. The reduction in optical gain at high activator concentrations is attributed to the concentration quenching in Nd3+ ion pairs. In addition to this, the dependence of the J-O parameters, several radiative properties of Nd3+ ions in the phosphate content as well as the nature of alkali content were also studied. |