Photorefractive damage, optical absorption, photoconductivities, and photogalvanic currents of stoichiometric LiNbO<sub>3</sub> single crystals with different Mg doping levels have been investigated. Nominally pure stoichiometric LiNbO<sub>3</sub> shows lower photorefractive damage resistance than congruent crystal; however, stoichiometric crystals doped with MgO of more than 1.8 mol. % exhibit no measurable photorefractive damage at 532 nm to intensities of as much as 8 MW/cm<sup>2</sup> . This remarkable damage resistance can be attributed not only to increased photoconductivity but also to decreased photogalvanic current. Stoichiometric Mg:LiNbO<sub>3</sub> also demonstrates the shortest absorption edge, 302 nm, and a single-domain nature with low scattering losses.
© 1998 Optical Society of America
(190.4400) Nonlinear optics : Nonlinear optics, materials
(190.5330) Nonlinear optics : Photorefractive optics
(260.5150) Physical optics : Photoconductivity
(300.1030) Spectroscopy : Absorption
Yasunori Furukawa, Kenji Kitamura, Shunji Takekawa, Kazuo Niwa, and Hideki Hatano, "Stoichiometric Mg:LiNbO3 as an effective material for nonlinear optics," Opt. Lett. 23, 1892-1894 (1998)