Spectroscopic properties of similar to 2 mu m emissions of Tm3+ doped germanate

Tm2O3-doped 40GeO(2)-35TeO(2)-15PbO-5Al(2)O(3)-2.5CaO-2.5SrO glasses with different Tm3+ ion concentrations are fabricated by conventional melt-quenching method. From the measurements of thermal properties it follows that the glass transition temperature is 446 degrees C and crystallization peak doe