Frequency upconversion of Er3+ in Ga2S3-GeS2-La2S3 glasses

Glasses containing Er3+ ions of 0.3 to 7 cation mol% were prepared in the system of Ga2S3-GeS2-La2S3. Frequency upconversion spectra of Er3+ in the glasses were measured under the excitation at 800 nn and 980 nn. Green emission at 533 mn (H-2(11/2)-->I-4(15/2)) and 552 nm (S-4(3/2)-->I-4(15/2)) and red emission at 665 nm (F-4(9/2)-->I-4(15/2)) were observed. In addition to these emission bands, 497 nm emission assigned to the F-4(7/2)-->I-4(15/2) transition was observed. The spectral properties are analyzed from the view points of low phonon energy property and high refractive index.