质子交换铌酸锂光波导的红外吸收光谱

Infrared Absorption Spectroscopy of Optical Waveguide in Proton-exchanged LiNbO_3

用尼高力 36 0型红外吸收光谱仪对用已二酸 (Adipicacid)和苯甲酸 (Benzoicacid)的不同摩尔比混合作为质子源进行质子交换制作的Z切铌酸锂光波导进行红外吸收光谱分析。表明 :OH-自由基团在 35 0 0cm-1处存在吸收峰 ,对应于质子交换中替代质子的特征 ,OH-氢键在 70 0cm-1处存在另一个吸收峰 ,对应于交换中的填充质子的特征。当两种不同的质子源以不同的摩尔比例混合时 ,质子源中的H+浓度不同 ,进行交换的速度也不同 ,结果导致在 35 0 0和 70 0cm-1两处的峰的强度发生变化。而这两个峰强度之比值可作为制作高质量铌酸锂光波导的重要依据 ,因此 。

Z-cut proton-exchanged LiNbO3 optical wave-guides exchanged with different proton sources mixed with adipic acid and benzoic acid in different mol ratios were analyzed by infrared absorption spectroscopy. The result shows that there is an absorption peak of OH- free group at 3 500 cm(-1) with the characteristic of substitute protons, and the absorption peak of H-bond is nearby 700 cm(-1) with the characteristic of packing protons. The different mixing ratios and different concentrations of H+ in the proton source, result in different proton-exchanged velocities and bring on the change in these absorption peaks. It is very important to study the change in these absorption peaks for making high quality LiNbO3 optical waveguide.