Ultra-broadband near-infrared emission in bismuth borosilicate glasses incorporated with Er3 +, Tm3 +, and Yb3 + ions

Abstract

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 800nm with a Ti:sapphire laser, a very broad emission band covering at 900–1700nm was found to appear due to overlapping of the emissions centering at 1003, 1266, 1536, and 1643nm 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 2mol% of Yb2O3.