Structural and spectroscopic properties of lead phosphate glasses doubly doped with Tb3+ and Eu3+ ions

The areas of the FT-IR bands related to all stretching modes of the PO bonds strongly depend on the relative ratio of the PbO and the P2O5 components. Several luminescence bands associated to characteristic transitions of trivalent europium and terbium are observed under direct excitation of Tb3+ ions. It indicates that the energy transfer process from Tb3+ to Eu3+ in lead phosphate glasses occurs.170