Miguel Jiménez de Castro

Active Er3+ doped lead-niobium-germanate planar waveguides produced by pulsed laser deposition

In this work, pulsed laser deposition has been used to produce Er3+ doped lead-niobium-germanate thin films from Er3+ doped 50Geo2-25PbO-25Nb2O5 transparent glasses with an Er2O3 content in the 0.5-3 weight % range. In all cases, by pumping the 4I11/2 level of Er3+, the as deposited films are optically active showing at room temperature the 4I13/2 →4I15/2 emission centered around 1530 nm. The luminescence intensity increases as the Er3+ content in the targets increases, whereas the opposite behavior is observed for the luminescence lifetime. The emission intensity and lifetimes of the 1.5 μm emission increase upon annealing.

Thermoluminescence in MgAl2O4 above 300K

Abstract Two peaks at 355 and 525K appear in the thermoluminescence spectrum of polycrystalline spinel X-irradiated at room temperature. They are due to thermally released electrons which recombine at several impurity centres as well as at V-centres. The influence of defects arising from the structural disorder and the non-stoichiometry of samples is discussed.