Strong UV absorption and visible luminescence in ytterbium-doped aluminosilicate glass under UV excitation.
A broad visible luminescence band and characteristic IR luminescence of Yb(3+) ions are observed under UV excitation in ytterbium-doped aluminosilicate glass. Samples made under both oxidizing and reducing conditions are analyzed. A strong charge-transfer absorption band in the UV range is observed for glass samples containing ytterbium. Additional absorption bands are observed for the sample made under reducing conditions, which are associated with f-d transitions of divalent ytterbium. The visible luminescence band is attributed to 5d-4f emission from Yb(2+) ions, and the IR luminescence is concluded to originate from a relaxed charge-transfer transition. The findings are important to explain induced optical losses (photodarkening) in high-power fiber lasers.
Engholm
M
M
Department of Information, Technology and Media, Physical Electronics and Photonics, Mid-Sweden University, SE-851 70 Sundsvall, Sweden. magnus.engholm@acreo.se
Norin
L
L
Aberg
D
D