Abstract
Energy transfer from Pr^<3+>,Nd^<3+>,Er^<3+> or Tm^<3+> to Gd^<3+> leading to Gd^<3+> emission at 312nm was observed in GdPO_4 doped with these ions under 172nm excitation. Among these ions, Pr^<3+> provides the strongest Gd^<3+> emission. Energy transfer from Gd^<3+> to Dy^<3+> was also observed under excitation by Gd^<3+> absorption at 276nm. As a result of this energy transfer, Gd^<3+> emission is quenched and strong, visible luminescence of Gd^<3+> appears. Such energy transfer processes are to be taken in account, when a quauntum cutting process using Gd^<3+> ions is investigated.
