کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5364349 | 1388315 | 2011 | 4 صفحه PDF | دانلود رایگان |
Alternate pulsed laser deposition from the host (Al2O3) and dopant (Er, Yb) targets has been used to prepare artificially nanostructured films in which the rare earth ion-ion separation is controlled in the nanometer scale in order to control energy transfer between ions. One series of films was prepared in the standard on-axis configuration, i.e. a static substrate being centred with respect to the plasma expansion axis. A second series of films was prepared by rotating the substrate with respect to a shifted axis parallel to the plasma expansion one (off-axis configuration). The latter configuration leads to films with enhanced thickness and Er related photoluminescence intensity uniformity. More interestingly, the Er related photoluminescence lifetime in as-grown films increases up to 2.5Â ms, which is much higher than the maximum value of 1Â ms obtained for the on-axis configuration films. This enhancement is discussed in terms of a decrease of defect density when using the off-axis configuration.
Research highlightsⶠPLD off-axis configuration provides larger film uniformity and enhanced PL lifetime for Er-doped as-grown thin films. ⶠPLD off-axis enables to decrease the impact of high kinetic energy species at the substrate centre, and consequently there is a decrease of induced defects. ⶠPLD off-axis configuration opens a route to prepare rare-earth doped materials with low defect densities and reduced Er-Er interaction.
Journal: Applied Surface Science - Volume 257, Issue 12, 1 April 2011, Pages 5204-5207