Ultraviolet and blue emission from crystalline SiO2 coated with LiNbO3 andLiTaO3

Citation
Gg. Siu et al., Ultraviolet and blue emission from crystalline SiO2 coated with LiNbO3 andLiTaO3, APPL PHYS L, 74(13), 1999, pp. 1812-1814
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
APPLIED PHYSICS LETTERS
ISSN journal
0003-6951 → ACNP
Volume
74
Issue
13
Year of publication
1999
Pages
1812 - 1814
Database
ISI
SICI code
0003-6951(19990329)74:13<1812:UABEFC>2.0.ZU;2-R
Abstract
Crystalline SiO2 (alpha quartz) coated with LiNbO3 (LN) or LiTaO3 (LT) film s emits two strengthened luminescence bands at 368 and 468 nm compared with those of pure alpha-SiO2, when excited with 280 nm light of a Xe lamp. The se two bands strongly depend on the coating: the LN-coated alpha-SiO2 has a much stronger photoluminescence (PL) than the LT-coated alpha-SiO2. On the other hand, the two bands are different from those of alpha-SiO2 in that t heir excitation spectra do not have any noticeable band in the range 200-32 0 nm. They could be understood based on excitons in the alpha-SiO2 surface, which are induced by the photorefractive effect of the coated films. The 3 68 nm PL band is attributed to the optical transitions of the E' defect pai rs and the 468 nm PL band to the radiative recombination of the self-trappe d excitons. (C) 1999 American Institute of Physics. [S0003-6951(99)01813-6] .