Investigation on broadband near-infrared emission and energy transfer in Er~(3+)-Tm~(3+) codoped germanate glasses

摘要

Broadband near-infrared emission has been investigated in a new type host composition of Er~(3+)-Tm~(3+) codoped germanate glass. A broadband emission extend from 1350 to 1675 nm with the full width at half maximum (FWHM) around 138 nm is obtained in the germanate glass which codoped with 0.2 wt.% Er_2O_3 and 0.8 wt.% Tm_2O_3. The energy transfer between Er~(3+) and Tm~(3+) plays an important role in the emission mechanism, which is evidenced by the visible upconversion and the lifetime of Er~(3+):~4I_(13/2) level effected by the addition of Tm_2O_3. And energy transfer efficiency from Er~(3+) to Tm~(3+) reaches 76% for the highest Tm~(3+) concentration of 0.8 wt.%. These results suggest that this glass would be a promising material for broadband light source and broadband amplifier for the wavelength division multiplexing transmission systems.