准相位匹配扇形光栅铌酸锂光波导倍频绿光输出

Fan-out Grating Quasi-Phase-Matched Second Harmonic Generation in LiNbO_3 Waveguide

采用外加电场极化方式对具有扇形光栅的 0 .5mm厚Z切铌酸锂晶体进行极化反转 ,制成了退火质子交换光波导。极化反转周期为 5 .8μm～ 6 .2 μm ,采用Nd∶YAG激光器输出的 1.0 6 4 μm连续激光为基频光波 ,实现了0 .5 32 μm倍频绿光输出 ,相互作用长度为 4mm ,耦入波导的基频光波功率为 10mW ,获得了 2 0 μW的绿色倍频光输出 ,归一化转换效率为 12 5 % (W·cm2 )。

The quasi phase matched second harmonic generation in periodically poled lithium niobate (PPLN) Z cut 0.5 mm thick annealed proton exchanged (APE) waveguide with fan grating was realized by applying an external field poling. The grating period ranges inverted from 5.8 μm～6.2 μm and the interaction length was 4 mm. Used a CW Nd∶YAG laser as a fundamental beam source at 1.064 μm, input power in waveguide was 10 mW. The green SHG of 20 μW at 0.532 μm was achieved at 125%/(W·cm 2) normalized conversion efficiency in PPLN waveguide.