Structural studies of tellurite glasses doped with erbium ions

The materials under investigation were the tellurite glasses. Basic glasses and glasses doped with erbium Er3+ ions were examined. The positron lifetime measurement method PALS (Positron Annihilation Lifetime Spectroscopy) and the Raman spectroscopy were applied in order to analyse their structural properties. The proposed PALS method allows to identify structural defects in amorphous materials (glasses, ceramics and polymers) that are difficult to detect with the use of other traditional measuring methods. The conducted studies revealed two positron lifetime components τ1 and τ2. On the basis of the two-state model, positron capture parameters were calculated, which allowed to draw conclusions concerning the nature and degree of defects of the examined tellurite glasses. Application of the Raman spectroscopy resulted in assessment of the effect of Er3+ on the structure of the examined material.