When a solid-state laser is excited at high average power, temperature differences within the laser material create stresses. These stresses along with the residual stress remaining from crystal growth make it difficult to extract efficiently polarized output from high-power Nd:YAG lasers using the traditional rod geometry. We demonstrated that both thermal and residual birefringence can be eliminated by using a geometry in which the laser beam zigzags through the laser material. Our observations and calculations indicate that it is possible to build an efficient 100-W Nd:YAG laser with polarized output and that it is not necessary to use stress-free Nd:YAG material.
© 1982 Optical Society of AmericaPDF Article