摘要
In this work, we have studied the concentration quenching in transparent glass ceramics containing Er^3＋：NaYF4 nanocrystals. For different concentrations, the emission spectra and decay curves of the ^4I/3/2 → ^4I15/2 emission were measured. The Er-concentration dependence of integrated intensity and lifetime of ^4I13/2→^4I15/2 emission are showed. With the increase of the Er^3＋ doping concentration, the 1.5 μm fluorescence emission first increases, then decreases, and the lifetime falls gradually. With 980 nm excitation, the efficiency of the energy transfer from Er^3＋ to quenching centers reaches 73.73% for the sample with 4 mol% Er^3＋. Meanwhile, owing to the relation of fluorescence integrated intensity and Er-concentration, a dipole-dipole quenching mechanism in the framework of a limited diffusion regime has been proved. Using the limited diffusion case, the critical concentration for quenching has been determined from a fitting equation of the lifetime and Er-concentration. The fit- ting result shows the critical concentration for quenching is higher than the values obtained in Er-doped different glass by an order of magnitude.
In this work, we have studied the concentration quenching in transparent glass ceramics containing Er3+:NaYF4 nanocrystals. For different concentrations, the emission spectra and decay curves of the 4I13/2→4I15/2 emission were measured. The Er-concentration dependence of integrated intensity and lifetime of 4I13/2→4I15/2 emission are showed. With the increase of the Er3+ doping concentration, the 1.5 m fluorescence emission first increases, then decreases, and the lifetime falls gradually. With 980 nm excitation, the efficiency of the energy transfer from Er3+ to quenching centers reaches 73.73% for the sample with 4 mol% Er3+. Meanwhile, owing to the relation of fluorescence integrated intensity and Er-concentration, a dipole-dipole quenching mechanism in the framework of a limited diffusion regime has been proved. Using the limited diffusion case, the critical concentration for quenching has been determined from a fitting equation of the lifetime and Er-concentration. The fitting result shows the critical concentration for quenching is higher than the values obtained in Er-doped different glass by an order of magnitude.
基金
supported by the Fujian Natural Science Foundation of China (Grant No. 2009J05139)
the Fujian Science and Technology major projects of China (Grant No. 2007HJ0004-2)
the Project of Education Department of Fujian Province of China (Grant No. JK2011008)
the Innovation Project for Young Scientists of Fujian Province of China (Grant No. 2007F3027)
