Thermal and luminescent properties of 2 μm emission in thulium-sensitized holmium-doped silicate-germanate glass

In this paper, we present the luminescent properties of Tm3+/Ho3+ co-doped new glass. A series of silicate-germanate glass was prepared by the conventional melt-quenching method. In the Tm3+/Ho3+ co-doped silicate-germanate glass, a strong emission of 2 mu m originating from the Ho3+:I-5(7) -> I-5(8) transition can be observed under conventional 808 nm pumping. The characteristic temperatures, structure, and absorption spectra have been measured. The radiative properties of Ho-3+ in the prepared glass were calculated. The emission cross section of Ho3+ ions transition can reach 4.78 x 10(-21) cm(2) around 2 mu m, and the FWHM is as high as 153 nm. The energy transfer efficiency between Ho3+ and Tm3+ has a large value (52%), which indicates the Tm3+/Ho3+ co-doped silicategermanate glass is a suitable candidate for the 2 mu m laser. Moreover, the energy transfer mechanism between Tm(3+)and Ho3+ ions was investigated. (C) 2016 Chinese Laser Press