Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1790510 | Journal of Crystal Growth | 2014 | 5 Pages |
•Four Nd:YAG crystals were grown by CZ method by varying initial melt composition.•The Nd concentration was measured along the crystals by optical absorption method.•Lambert W-function was used to solve the Scheil equation for calculation of keff.•The equilibrium segregation and diffusion coefficients for Nd:YAG were determined.
In this paper, a new mathematical model has been presented to determine the equilibrium segregation (k0) and effective segregation (keff) coefficients for neodymium (Nd) in YAG crystal grown by Czochralski (CZ) method. Determination of diffusion coefficient (DL) of Nd impurity in molten YAG is also investigated. In this model, utilizing Lambert W-function is a new idea to solve the Scheil equation for calculation of effective segregation coefficient. The Nd concentration in the crystal has been measured by optical absorption method to calculate keff. The analyses show that the keff is related to the growth parameters such as crystal growth rate (ug) and crystal rotation rate (ω ), (keff~ug/ω) but it is independent of the Nd concentration in the initial melt (C0). Based on obtained keff and experimental growth data, k0 and DL of Nd in molten YAG have been calculated. For all experiments, the average value of k0=0.216 and DL=1.4×10−6 (cm2/s) are obtained. Our results are corroborated by the theoretical and experimental data from the literature.