Luminescence properties of phosphors based on Tb3Al5O12 (TbAG) terbium-aluminum garnet

The processes of excitation energy transfer in phosphors based on single-crystal Tb 3 Al 5 O 12 :Ce (TbAG:Ce) and Tb 3 Al 5 O 12 :Ce,Eu (TbAG:Ce,Eu) garnet films have been investigated. These films are considered to be promising materials for screens for X-ray images and luminescence converters of blue LED radiation. The conditions for excitation energy transfer from the matrix (Tb 3+ cations) to Ce 3+ and Eu 3+ ions in TbAG:Ce and TbAG:Ce,Eu phosphors have been analyzed in detail. It is established that a cascade process of excitation energy transfer from Tb 3+ ions to Ce 3+ and Eu 3+ ions and from Ce 3+ ions to Eu 3+ ions is implemented in TbAG:Ce,Eu via dipole-dipole interaction and through the Tb 3+ cation sublattice.