About the luminescence properties of YAG∶Nd, Ce and YAG∶Nd single crystals and their relation to laser properties

Laser excited luminescence studies of various YAG∶Nd, Ce and YAG:Nd (with an excess of yttrium) single crystals together with a testing of laser properties of rods made from the same crystals have been investigated in this paper. It was observed that laser pulse energies increase with increasing halfwidths of the luminescence spectral bands. This dependence and other observations indicate that local structure changes or Nd³⁺ nonequivalent centres are present in the studied crystals. Various mechanisms leading to the formation of Nd³⁺ nonequivalent centres are discussed and it seems that the more probable mechanism is oxygen segregation and diffusion.