[en] Spatial and temporal distribution of quantum efficiency of energy transfers in crystals of lithium niobate with non-uniform concentration profiles of Er"3"+ and Yb"3"+ ions has been studied for the cases of Yb"3"+-Er"3"+ Foerster transfer and radiative decay of upper energy levels of erbium ions (green and red luminescence). (paper)

[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] The influence of optical centers concentration profiles on thermal fields under high-power end-face diode pumping is analyzed using numerical model. It is shown that non-uniform distribution profiles of optical centers concentration are very promising for high average pump power laser amplifiers. The possibility of creating concentration profiles of optical centers in gradient-activated crystals with YAG matrix with a specified distribution along the growth axis of the crystal is demonstrated. A technology of growing gradient-activated single crystal involving active mirror as active element is proposed and discussed. (paper)