化学计量比LiNbO_3晶体的光折变损伤阈值测定

The Measurement of Photorefractive Damage Threshold of Near-stoichiometric LiNbO_3 Crystals

运用准连续激光器测定了4种用助熔剂提拉法生长的化学计量比铌酸锂(LiNbO3)晶体的光折变损伤,应用高斯光束经凸透镜变换的公式计算了光斑半径,最后得到了光损伤阈值,并与同成分LiNbO3作了比较,讨论了掺杂对晶体光折变性能的影响。根据晶体红外吸收峰的位置定性判断了晶体的光损伤阈值,其结果与准连续激光器的测量结果是一致的。

The photorefractive damage of four kinds of nearstoichiometirc LiNbO3 crystals were measured with the quasicw laser,those crystals were successfully grown with flux pulling method.The radius of laser beam were calculated on the basis of the equations that the Gauss beam is transferred by the convex.At last the damage thresholds were got,meantime compared with congruent LiNbO3,the doped ions impact on the photorefractive properties of crystals also were discussed.In addition,according to the positions of infrared absorption peak,the photorefractive damage thresholds are qualitatively judge,whose results are consistent with the metrical outcomes.