Enhanced multiphoton ultraviolet and blue upconversion emissions in Y 2O3 : Er3+ nanocrystals by codoping with Li+ ions

Autor:	Gabriel Somesfalean, H.J. Liang, Haichun Liu, Zhiguo Zhang, G.Y. Chen
Rok vydání:	2008
Předmět:	Photoluminescence business.industry Chemistry Doping General Chemistry Condensed Matter Physics Laser Photochemistry medicine.disease_cause Photon upconversion law.invention Ion Nanocrystal law Materials Chemistry medicine Optoelectronics business Excitation Ultraviolet
Zdroj:	Solid State Communications. 148:96-100
ISSN:	0038-1098
DOI:	10.1016/j.ssc.2008.08.001
Popis:	Ultraviolet (UV) and blue upconversion (UC) radiations with large and anomalous enhancement were observed in Y 2O3:Er3+ nanocrystals under laser excitation of 970 nm. Three-photon UV and blue UC radiations were enhanced by about 60 times via codoping with Li+ ions, in remarked contrast to the 45 times enhancement for two-photon green UC radiation. The integrated intensity of enhanced UV and blue UC radiations in Y 2O3:Er3+, Li+ nanocrystals can reach about half that in Y 2O3:Er3+ ceramic bulk. Such anomalous enhancement behavior for UV and blue UC radiations originates from the fact that the tailored lifetime of the S 3 / 2 4 state was further involved for their generation, contrasted to the green UC emission involving only the tailored lifetime of the I 11 / 2 4 state. Theoretical calculations based on steady state equations evidenced these conclusions.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::519534061ff6261ff678afb2dcd5637f https://doi.org/10.1016/j.ssc.2008.08.001 Zobrazit plný text záznamu Full Text from ScienceDirect