Ultra-broadband near-infrared emission in bismuth borosilicate glasses incorporated with Er3Â +, Tm3Â +, and Yb3Â + ions

Bismuth containing glasses are interesting photonic materials due to their broadband emission properties in the near-infrared wavelength range. Bismuth alumino-borosilicate glasses co-doped with Er3 +, Tm3 +, and Yb3 + ions were prepared by the conventional glass melting process and their optical absorption, near-infrared emission, and lifetime characteristics were investigated. Upon pumping at 800 nm with a Ti:sapphire laser, a very broad emission band covering at 900-1700 nm was found to appear due to overlapping of the emissions centering at 1003, 1266, 1536, and 1643 nm from the co-doped ions of Yb3 +, Bi, Er3 +, and Tm3 +, respectively. The emission intensity and the lifetime of the emission bands were significantly influenced by the addition of Yb2O3. The pump energy absorbed by Bi was transferred to Yb3 + and Er3 + ions and the amount of the transferred energy was enhanced with the increase of Yb2O3. The energy transfer efficiency from Bi to the co-doped rare earth ions was ~ 4.0% at 2 mol% of Yb2O3.