Optically dense active media for solid-state lasers

摘要

The author has examined the potential of optically dense active media in solid-state lasers using, as an example, YSGG:Cr/sup 3+/,Nd/sup 3+/ active elements with a chromium concentration=1*10/sup 20/ cm/sup -3/, and a neodymium concentration=3*10/sup 20/ cm/sup -3/. One element had a square cross section (dimensions were 0.5*0.5*8 cm/sup 3/) and the other was cylindrical (0.4-cm-diameter, 7-cm-long). The optical density and geometrical size were chosen so that the limiting pump regime would be encountered at a relatively low average power. The solid-state laser pump cavity was cylindrical. This made it possible to compare the square (zig-zag) and cylindrical active elements under identical conditions. The results are presented. An effect, called the static STON-effect (smoothing of thermo-optical inhomogeneities), is discussed.