Luminescence of Mn2+ ions in Tb3Al5O12 garnet

The paper is dedicated to investigation of the Mn2+ luminescence in Tb3Al5O12 (TbAG) garnet, as well as the processes of excitation energy transfer between host cations (Tb3+ ions) and activators (Mn2+ and Mn2+-Ce3+ pair ions) in single crystalline films of TbAG:Mn and TbAG:Mn,Ce garnets which can be considered as promising luminescent materials for conversion of LED's radiation. Due to the effective energy transfer between TbAG host and activator, Mn2+ ions in TbAG possess the bright orange luminescence in the bands peaked at 595 nm with a lifetime of 0.64 ms which are caused by the 4T1→6A1 radiative transitions. The simultaneous process of energy transfer is realized in TbAG:Mn,Ce: (i) from Tb3+ to Mn2+ ions; (ii) from Tb3+ cations to Ce3+ ions and then partly to Mn2+ ions through Tb3+ ion sublattice and Ce-Mn dipole-dipole interaction.