Absorption and emission properties of Tm2+ ions in germanosilicate glass fibers

Abstract

Absorption and emission properties between 350nm and 1600nm of the Tm2+ ions in optical fibers were investigated using the Tm2+-Tm3+ co-doped germanosilicate glass fibers and its fiber preform. Strong broad absorption band due to Tm2+ ions was found to appear from 350nm to similar to900nm together with the absorption bands due to Tm3+ ions. Broad emission from similar to600nm to similar to1050nm and the other emission from similar to1050nm to similar to1300nm, which were not shown in the Tm3+ ions, were found upon the Ar ion laser pumping at 515nm. Both absorption and emission results confirm that the Tm2+ ions in the germanosilicate glass have the 4f-5d energy band from 350nm to similar to900nm and the 4f-4f energy level at similar to1115nm. (C) 2003 Optical Society of America.