Lanthanide level location and charge carrier trapping in LiLnSiO4:Ce3+,Sm3+, Ln = Y or Lu

By doping an inorganic compound with two specific types of trivalent rare-earth impurities the controlled creation of electron- and hole-trapping centres is possible. This is demonstrated with experimental data on LiLnSiO 4 :Ce 3+ , Sm 3+ , Ln = Y or Lu. After exposure to ionizing radiation electrons are captured by Sm 3+ and holes are captured by Ce 3+ . The electron trapping depth is given by the energy difference between the Sm 2+ ground state and the bottom of the conduction band. This energy is estimated from the energy of charge transfer from the valence band to Eu 3+ employing recently developed models. The trapping energy is also determined from thermoluminescence studies. Both values are in good agreement.