The luminescence of crystals doped with rare-earth ions (Nd3+, Er3+) was investigated in the visible and near-infrared spectral ranges. Crystal doping was achieved by addition to the melt and by a diffusion method. The diffusion profiles of rare-earth ions in the crystals were measured by using the luminescence method. The luminescence parameters of crystals doped by diffusion were compared with those for crystals doped by adding Nd3+ and Er3+ to the melt. Two processes of rare-earth ion transport were observed, and were explained by 2 different diffusion mechanisms. High values of the diffusion coefficient for rare-earth ions in these crystals made it possible to prepare doped crystals of high optical quality.

Rare Earth Ion Diffusion in AgBr Crystals. L.Nagli, A.German, A.Katzir: Optical Materials, 1999, 13[1], 89-95