Infrared emission and energy transfer in Tm^3+, Tm^3+-Ho^3+ and Tm^3+-Yb^3+-doped tellurite fibre

Preparation and Characterization of Downconversion Luminescent LaVO4: Tm3+ , Yb3+ and Tm3+ /Yb3+ Nanosheets

Tm3+ , Yb3+  and Tm3+ /Yb3+  doped LaVO4 nanostructures were synthe- sized for the first time by using the hydrothermal method with the aid of La(CH3CO2)3 as  lanthanum source in presence of oleic acid as surfactant. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL) spectroscopy and ...

Critical separation for efficient Tm3+ -Tm3+ energy transfer evidenced in nanostructured Tm3+: Al2O3 thin films.

Nanostructured amorphous Al oxide (a-Al2O3) thin films doped with Tm3+ were synthesized by alternate pulsed laser deposition. The Tm3+ ions have been deposited in layers with in-depth separation ranging from 0.75 to 6 nm. The films show two broad emission bands originated from the Tm3+ 3H4-->3F4 and 3F4-->3H6 transitions. Their intensity increases at a similar rate and the lifetimes are not mod...

Synthesis and upconversion luminescence of YF3:Yb3+ Tm3+ and TiO2-coated YF3:Yb3+, Tm3+ microcrystals.

YF3:Yb3+, Tm3+ microcrystals were prepared by a microemulsion method. The microcrystals were coated with TiO2 by hydrolysis of titanium n-butoxide (TBOT). Transform electron microscopy and X-ray diffraction were used to characterize the core/shell materials. The results indicated that the low TBOT/YF3 molar ratio was favorable to preparing the uniform TiO2 coatings. The upconversion luminescenc...

Energy transfer up-conversion in Tm3+-doped silica fiber

A study of the mechanisms responsible for the infra-red to near infra-red up-conversion in thulium doped silica fibres is presented. Up-conversion luminescence was observed from the H4 level of Tm under 1586 nm pumping into the F4 level. The quadratic dependence of the up-conversion luminescence at 800 nm on the 1800 nm luminescence from the F4 level confirms that the H4 level is populated by a...

Energy transfer efficiency in YF3 nanocrystals: Quantifying the Yb3+ to Tm3+ infrared dynamics