UP-CONVERSION PROPERTIES OF ER3-GLASSES( DOPED LEAD SILICATE)

We report the spectroscopic behaviour of the Er3+ ion in two lead sili cate glasses containing different concentrations of PbO. Evidence is g iven for blue and green upconversion fluorescence in the two Er3+ dope d lead silicate glasses with the use of 650 nm, 800 nm and 1.5 mu m ex citation. Analysis of the results shows that upconversion occurs via t he sequential absorption of photons from the metastable I-4(13/2) stat e. Furthermore, we show that upconversion is facilitated due to the lo w radiative transition probabilities and to the inefficient multiphono n relaxation.