Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5399675 | Journal of Luminescence | 2014 | 4 Pages |
Abstract
In the present work, we have studied the photoluminescence (PL) and decay lifetime of Tb and Eu nanoparticles (NPs) at low temperatures. The NPs were obtained by ion implantation into a SiO2 matrix. Concerning the PL emission of Tb NPs (from 370 to 700Â nm), the shape does not change with the sample temperature and the PL yield has a maximum at 12Â K and decreases with increasing temperature, reaching a minimum at 300Â K. The PL lifetime is wavelength independent and remains almost constant at a value of 1.5Â ms. Regarding Eu NPs emission, two spectral regions were identified, one with narrow emission bands (from 570 to 750Â nm) and the other with a broad emission band (from 400 to 550Â nm). Both PL regions show a minimum yield at 12Â K, and next it rises with increasing temperatures, reaching the maximum at around 100Â K. Then, the PL yields start to decrease, reaching at 300Â K a value similar to the one obtained at 12Â K. For the Eu NPs PL lifetime, two different results were obtained. The long wavelength spectral region shows a lifetime of the order of 1.0Â ms independent of the temperature. Conversely, the short wavelength one is strongly temperature dependent, being of the order of several milliseconds for temperatures lower than 100Â K down to 0.05Â ms at 300Â K.
Keywords
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Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
F.L. Bregolin, P. Franzen, H. Boudinov, U.S. Sias, M. Behar,