Novel composite structure Nd : YAG gain media for high power scaling of side-pumped configurations

We test two novel, side-pumped fused and optically contacted composite Nd:Y AG slabs where the laser mode propagates parallel to the layer boundaries. Although these composite rods provide output and beam quality comparable to standard side pumped rods, we measure significant beam distortion near lay er boundaries, We show through detailed calculation and experiment that sca ttering near layer boundaries in these composite structures is mostly due t o the small index of refraction difference between Nd:YAG and undoped YAG. (C) 2000 Elsevier Science B.V. All rights reserved.