On the solubility of Nd3+ in Y3Al5O12
|Detlef Klimm 1, Steffen Ganschow 1, Anna Pajaczkowska 2, Ludwika Lipińska 2|
1. Leibniz Institute for Crystal Growth (IKZ), Max-Born-Str 2, Berlin 12489, Germany
Neodymium doped yttrium aluminum garnet (Nd:YAG or (Y1−xNdx)3Al5O12) is one of the most important laser materials. Crystals are available from different commercial suppliers with dopant concentrations up to 2.5 at% (x ≤ 0.025). The crystals are grown from the melt usually by the Czochralski method. Besides, in the framework of this study Nd:YAG crystals with different doping levels are grown by the micro-pulling-down method. For both methods, the material has to be kept at the melting point that is for undoped (x=0) Y3Al5O12 Tf = 1940°C and drops only slightly for x>0. Alternatively, single phase (Y1−xNdx)3Al5O12 powders with doping levels as high as x = 0.275 could be produced in a low-temperature sol-gel process. DTA measurements up to Tf showed that the highly doped Nd:YAG powders are in thermodynamic equilibrium only up to (depending on x) T ≅ 1650°C and decompose irreversibly at higher T. These results can be understood if the crystals are considered as solid solutions within the concentration triangle Al2O3 – Y2O3 – Nd2O3. Based such treatment a pseudo-binary "garnet" section of this concentration triangle will be proposed that explains the experimental findings known so far.
Presentation: Invited oral at Joint Fith International Conference on Solid State Crystals & Eighth Polish Conference on Crystal Growth, by Detlef Klimm
See On-line Journal of Joint Fith International Conference on Solid State Crystals & Eighth Polish Conference on Crystal Growth
Submitted: 2007-01-04 14:43 Revised: 2009-06-07 00:44