Non-radioactive energy transfer processes and luminescent quantum efficiency in laser crystals

The non-radiative energy transfer processes are identified for the luminisc ent system Nd(1.1 at.%):YAG and their effects upon the luminiscent quantum efficiency. In comparison to other calculations for this system and for the transfer processes, donor and acceptor ions are identified among the same neodymium ions. Thus, donor and acceptor ions correspond to ions that occup y non-perturbed and perturbed sites, respectively. The interactions respons ible for the transfer processes are dipole-dipole, dipole-quadrupole, quadr upole-quadrupole and exchange. Our calculations for the luminiscence of the F-4(3/2) State of neodymium ions fit the experimental measured data. The e xperimental data show a fast initial decay followed by a non-exponential de cay at longtime. The calculated luminiscent quantum efficiency is 0.75.