Photoluminescence quenching in Er-doped compounds

The temperature-induced quenching in the photoluminescence intensity (IPL) of Er3+ ions in different semiconductor hosts is discussed in this letter. Based on a compilation of several IPL(T) experimental curves, corresponding to either crystalline or amorphous Er-doped samples, and after a critical data analysis, it was possible to determine a temperature of quenching Tq such that IPL(Tq)=0.95 IPL (lowest T). These experimental Tq values have been analyzed in terms of certain host characteristics such as optical band gap and phonon frequency. As a result of this study it was possible to state that: (i) Tq strongly depends on the optical band gap and atomic structure of all studied semiconductor hosts; (ii) the host phonon frequency plays a minor role in the quenching of IPL; and (iii) based on the partial ionic character of each semiconductor host, both the energy and the localization of the photon-generated electron–hole pairs determine the IPL quenching. Moreover, the present phenomenological model is consistent with the influence that codoping and thermal anneals have on the IPL enhancement of Er-doped compounds.