[en] This paper considers the effect of the longitudinal lithium concentration distribution in PPLN converters on their efficiency in high-power cw laser second harmonic generation. (nonlinear optical phenomena)

[en] We studied the effect of the growth cell geometry on the temperature fields and the uniformity of semiconductor layers grown by thermal crystallization method from a discrete liquid source. Calculation results show that the radius of local sources practically does not change the temperature field of the substrate. When the radius of the local evaporators was changed from 2 to 6.5 mm, the observed increase in the maximum temperature did not exceed 2 K. However, increasing the distance between the substrate and the temperature screen fundamentally changes the temperature of the substrate. An increase in the distance from 2 to 25 mm caused a decrease in the substrate temperature by 20 K. It is shown that to achieve uniformity of better than 90% need to use a hexagonal arranged system of round local sources with the radius of r = 0.6 cm. (paper)