Amplifiers for neodymium laser systems with a homogeneous distribution of the gain

Measurements were made of the gain of cylindrical active elements of different diameters placed in elliptical illumination enclosures. A high degree of homogeneity of the azimuthal distributions of the gain was achieved when the semiaxis of the elliptical enclosure was approximately equal to the visible diameter of the active rod. The radial distributions were homogeneous when elements of GLS1 glass were used. An empirical dependence of the maximum gain per unit length on the radius of an active rod placed in an enclosure of this type was determined.