准相位匹配周期极化掺镁铌酸锂490nm倍频连续输出

Continuous-wave Quasi-phase-matched Second Harmonic Generationat 490 nm in Periodically Poled MgO:LiNbO_3

在室温下通过外加电场极化法 ,首次用较低的极化开关电场～ 5 .5kV/mm ,在厚为 1mm、长为 2 0mm、宽为 18mm的掺镁铌酸锂基片上成功的制备了周期为 4 .8～ 5 .2 μm的一阶准相位匹配倍频光学微结构 ;并在室温下 ,以波长为 980nm的半导体激光器为基频光源 ,对所研制的微结构样品进行倍频通光实验 ,在入射基频光为 80 0mW时 ,产生约 4 0mW的 4 90nm的倍频光 ,其对应转换效率为 5 % 。

A first order quasi-phase-matched periodically poled micro-structure MgO∶LiNbO 3 for SHG with 4.8～5.2 μm period, 20 mm length, 18 mm width and 1 mm thickness has been successfully fabricated by applying an external field at room temperature. Because the switching field of MgO∶LiNbO 3 is ～5.5 kV/mm, which is approximately one fourth that of the conventional congruent field, periodic poling of thicker MgO∶LiNbO 3 substrates was successfully performed by means of an electric field poling process at room temperature. Using the sample to double the frequency of a diode laser at 980 nm was studied. About 40 mW of CW 490 nm blue light was obtained pumped by 800 mW of the fundamental power, which corresponds to 5% power conversion efficiency. No obvious optical damage has been observed.