Crystallization effect on Tm3+–Yb3+ codoped SBN glass ceramics

An appropriated thermal treatment of SrO–BaO–Nb2O5–B2O5 glass leads to the formation of glass ceramics which are composed of Tm3+–Yb3+ codoped strontium barium niobate (SBN) nanocrystals dispersed throughout an amorphous matrix. The glasses have been fabricated using a melt-quenching method and after a thermal treatment at 620 °C have been obtained the glass ceramic samples. The formation of SBN nanocrystals has been confirmed by the X-ray diffraction patterns. Visible and NIR emission spectra have been reported and confirmed the incorporation of the Tm3+–Yb3+ ions into the SBN nanocrystals. In the glass ceramics samples the decays of Tm3+ levels for the Yb3+–Tm3+ codoped samples are longer than in the Tm3+ single doped samples. This surprising result could be explained in basis to the localisation of the active ions in the SBN nanocrystals.