Up-conversion luminescence in Yb(3+)-Er(3+)Tm(3+) co-doped Al(2)O(3)-TiO(2) nano-composites.

The sol gel method was used to prepare rare-earths (Yb-Er and Yb-Tm) co-doped AlO-TiO nano-composite powder phosphors and their up-conversion luminescence properties were investigated. Mixed oxides of titania (TiO) rutile phase and an early stage crystallization of alumina (AlO) phase were confirmed from the X-ray diffraction data with the average crystallite size of ∼36nm. The rutile phase TiO was further confirmed by selected area diffraction analysis of the composites.