Photon cascade emission and quantum efficiency of the 3P0 level in Pr3+-doped SrAl12O19 system

Photon cascade emission has been reported in Pr3+ -doped SrAl12O19 system, providing a unique method for direct measuring the quantum efficiency of (3)p(0) in this material. The S-1(0) --> I-1(6) fluorescence intensity can be taken as a measure of the initial (3)p(0) population. Thus the quantum efficiency of (3)p(0) can be calculated using the intensity ratio of the total emission from (3)p(0) and the emission Of S-1(0) --> I-1(6). The efficiency decreases as the concentration of Pr increases, indicating the effect of concentration quenching. The quantum efficiency is still, substantially less than 100% even in dilute sample due to the thermal excitation Of I-1(6) and (3)p(1) states. (C) 2003 Elsevier Science B.V. All rights reserved.