Structural, thermal, and optical properties of Er3+/Yb3+ co-doped oxyhalide tellurite glasses, glass-ceramics and ceramics

Glass-ceramics and ceramics containing nano-crystals of different phases doped with Er3+/Yb3+ ions have been successfully prepared by heat treatment of the precursor oxyhalide glasses synthesized by the melt-quench method. X-ray diffraction patterns and transmission electron microscopy (TEM) images verify the precipitation of nano-crystals. Emission of Er3+ enhances several times when Yb3+ ion is added with the matrix. The Stark splitting and the intensity of different emission bands increase to a great extent when we approach to ceramics from glasses via glass-ceramics. The intensity of the blue and green emission bands increases much faster than the red and NIR emission bands. Intense upconversion emission observed by the naked eye has been quantified in terms of standard chromaticity diagram (CIE). Power dependence study shows that the upconversion of NIR radiation to visible radiation takes place mainly via photon avalanche (PA) process.

► Effect of ceramization on the structural and optical properties has explored. ► Above mentioned properties improve towards ceramization. ► Emission spectra recorded with 532 nm laser source show different behavior. ► Photon avalanche has also observed in critical power region of 976 nm diode laser. ► CIE diagram shows the overall emission of glasses, glass-ceramics, and ceramics.