Broadband Infrared Luminescence from Bismuth-Doped GeS₂--Ga₂S₃ Chalcogenide Glasses

Near-infrared luminescence is observed from bismuth-doped GeS₂--Ga₂S₃ chalcogenide glasses excited by an 808nm laser diode. The emission peak with a maximum at about 1260nm is observed in 80GeS₂--20Ga₂S₃:0.5Bi
glass and it shifts toward the long wavelength with the addition of Bi gradually. The full width of half maximum (FWHM) is about 200nm. The broadband infrared luminescence of Bi-doped GeS₂--Ga₂S₃ chalcogenide glasses may be predominantly originated from the low valence state of Bi, such as Bi⁺. Raman scattering is also conducted to clarify the structure of glasses. These Bi-doped GeS₂--Ga₂S₃ chalcogenide glasses can be applied potentially in novel broadband optical fibre amplifiers and broadly tunable laser in optical communication system.