Abstract

Much research into self-doubling laser crystals has occurred in recent years, with the focus being Nd:YAB [1], a negative uniaxial crystal. It allows high Nd doping (up to 40 times that in Nd:YAG), and has a high emission cross-section, thus permitting efficient Nd laser operation at 1.06 mm. In addition, the high non-linear coefficient suggests that it should be efficient as a self-doubling crystal [2], However, it has a number of disadvantages. While the crystal growth direction is parallel to the principal optical axis, it is difficult to grow because the neodymium ions are larger than the yttrium ions, and thus do not substitute easily into yttrium sites of the YAB crystal lattice, consequently causing lattice distortion and reduced optical quality. A second disadvantage is that the Nd ions absorb at the frequency -doubled green wavelength of 530 nm, and thus reduce the efficiency of visible light generation. Power-scaling prospects using this crystal are thus limited by consequent thermal problems.

© 1996 Optical Society of America