resumo
Trivalent neodymium (Nd3+) can be used as high performance temperature luminescent ion sensor, namely in the near infrared spectral region. The disadvantage presented in the use of this ion is that transitions from thermally coupled levels show very different emission intensities. In order to solve this critical problem we propose to use Nd3+-doped fluoroindogallate glasses with low phonon cutoff energy (500 cm(-1)) as the active medium. By using a dopant concentration that minimizes losses due to cross relaxation processes and detecting the emissions of the thermally coupled levels with a R928 photo multiplier, without correction response for the wavelength dependence of the intensity, we have succeeded in getting the highest relative thermal sensitivities so far observed, 2.5%.K-1 and 7.4%.K-1, for the F-4(5/2) -> I-4(9/2)/F-4(3/2) -> I-4(9/2) and F-4(7/2) -> I-4(9/2)/F-4(3/2) -> I-4(9/2) intensity ratios, respectively at 288 K. (C) 2016 Elsevier B.V. All rights reserved.
palavras-chave
OPTICAL-TEMPERATURE SENSORS; INTENSITY RATIO TECHNIQUE; RARE-EARTH IONS; NANOPARTICLES; ND3+; NANOTHERMOMETERS; NANOSCALE
categoria
Materials Science; Optics
autores
Nunes, LAO; Souza, AS; Carlos, LD; Malta, OL
nossos autores
Luís Carlos
Professor Catedráticoagradecimentos
The financial support of FAPESP, CAPES and CNPq (Brazilian agencies) are acknowledged. This work was partially developed in the scope of the project CICECO Aveiro Institute of Materials POCI-01-0145-FEDER-007679 (Ref. FCT UID/CTM/50011/2013), financed by Portuguese funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. LDC is grateful to CAPES and CNPq for a fellowship within the science without borders program,