Upconversion Luminescence Properties of a LiNb 0.3 Ta 0.7 O 3 :Er ,Yb Ceramic.

A co-doped LiNb0.3Ta0.7O3:Er3+,Yb3+ceramic was prepared by a high temperature solid state procedure. Under the excitation of 980 nm laser radiation, intense 660 nm red light and 550 nm green light emissions corresponding to the4F9/2→4I15/2and2H11/2/4S3/2→4I15/2transitions of Er3+were observed. The change of Yb3+concentration has a more significant influence on luminous intensity than the Er3+concentration. The emission of red and green lights is attributed to a two-photon process. The upconversion luminescence mechanisms were analyzed in detail. [ABSTRACT FROM AUTHOR]