Luminescence properties of Ca 4GdO(BO 3) 3:RE (RE=Eu 3+,Tb 3+) under VUV excitation

We experimentally investigated the VUV excitation luminescence properties of Ca 4GdO(BO 3) 3:RE (RE=Eu 3+, Tb 3+). Ca 4GdO(BO 3) 3:Eu 3+ and Ca 4GdO(BO 3) 3:Tb 3+ emitted bright red and green colour light, respectively, under 172nm excitation, resulting from the favorable position of the host absorption band (186 nm) and efficient energy transfer from Gd 3+ to activators (e.g. Eu 3+ or Tb 3+) by means of secondary absorption in the Ca 4GdO(BO 3) 3 matrix. The f-d transitions of Eu 3+ and Tb 3+ in the host lattice are depicted. ©2005 Chinese Physical Society and IOP Publishing Ltd.