采用热蒸发沉积技术制备了钛酸镧(H4)薄膜, 研究了1 064 nm和532 nm波长激光诱导辐照处理后的薄膜折射率、消光系数、激光损伤阈值和损伤过程变迁.结果表明：采用不同波长的激光辐照H4薄膜后, 会使其折射率升高, 但升高的幅度不大.用1 064 nm的激光辐照处理, 可将H4膜的激光损伤阈值从10.2 J/cm2提高到 15.7 J/cm2(5脉冲辐照), 而532 nm激光辐照对样品损伤阈值的提高效果不明显.同一样片, 1 064 nm激光的损伤阈值远远高于532 nm的激光损伤阈值.1064 nm激光辐照下, H4薄膜经历了轻微损伤、轻度损伤、重度损伤和极度损伤四个缓慢演变的阶段.而532 nm激光辐照下, H4薄膜从未损伤到损伤是一个突变的过程, 经历了重度损伤和极度损伤的演变阶段.

Lanthanum titanate (H4) films were deposited by the thermal vapor deposition technique. After irradiating with a 1 064 nm and 532 nm lasers, the refractive index, extinction coefficient, Laser-Induced Damage Threshold (LIDT) of the films and damaging process of the films were investigated. The results showed that the refractive index of H4 films slightly increased after laser irradiating. The LIDT increased from 10.2 J/cm2 to 15.7 J/cm2 (5-pulse irradiation) after irradiating by using a 1 064 nm laser, however, the change of LIDT of the films was unobvious after irradiating by using a 532 nm laser. For the same sample, the LIDT which measured with a 1 064 nm laser was higher than that with a 532 nm laser. H4 film′s damage process underwent a slow 4-stage, slight, mild, moderate and extreme damage by using a 1 064 nm laser, whereas the damage process was a sudden change by using a 532 nm laser, underwent a 2-stage, moderate and extreme damage..