The optimization of near infrared CW Gd3Ga5O12:Nd-,YAIO3:Nd- AND YVO4:Nd- microlasers
The modeling of CW GGG:Nd- (1.4237 mum), YAP:Nd- (1.34 mum), YVO4:Nd-microlasers (1.0643 mum) is carried out. At that for the each fixed value of the incident pumping power and the laser beam divergence the optimal values of the activator concentration, the active medium length and the reflectivity of the output mirror, i.e. the values that maximize the laser power, are determined.
Concentration distribution of Nd3+ In Nd:Gd3Ga5O12 crystals studied by optical absorption method
Nd:Gd3Ga5O12 crystals with different concentrations of Nd3+ were grown by Czochralski method, their absorption spectra were measured at room temperature. By using the optical absorption method, the effective distribution coefficient keff for Nd3+ in GGG was fitted to be 0.40±0.01, which is higher than that of Nd3+ in YAG. The 808nm absorption cross‐section was calculated to be 4.0±0.2×10‐20cm‐2. The lengthways and radial concentration distribution of Nd3+ in the crystals were also analyzed and discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effective distribution coefficient of neodynium in Nd:Gd3Ga5O12 crystals grown by the Czochralski method
Abstract The effective distribution coefficient k eff for Nd in Nd doped Gd 3 Ga 5 O 12 (Nd: GGG) crystals, grown by the Czochralski method, was determined over the concentration range 0.2–5.9 at% Nd in crystal. The Nd concentration in the crystal was measured by a fluorescent X-ray analysis to estimate the distribution coefficient. The k eff obtained showed a tendency to increase with increasing Nd concentration, relating to the homogeneity of the grown crystals. The optical absorption by Nd 3+ in the crystal at the 481.3 nm absorption peak was also measured. Using this method, the Nd concentration at the only homogeneous part of the crystal could be observed selectively. A value of k eff =0.41±0.02 was obtained by the optical method. The value obtained appeared to be independent of the Nd concentration in the initial melt.