Abstract
Silicate glasses, Al2O3⋅9SiO2, were successfully prepared to incorporate Sm2+ ions using a sol‐gel process. The glasses synthesized through hydrolysis of Si(OC2H5)4, Al(OC4H9)3, and SmCl3⋅6H2O were heated in air, followed by heating in the presence of hydrogen, in which samarium ions were reduced from the trivalent to divalent state. Glasses incorporated with Sm2+ were colorless, transparent, and showed an intense emission with peaks at 683, 700, and 725 nm due to 5 D 0→7 F 0,1,2transitions, respectively, of the Sm2+ ions. Irradiating the glasses with an Ar laser lowered the intensities of emission from Sm2+ ions and did not promote the formation of Sm3+ ions.