准速度匹配相位调制器钽酸锂晶体的室温电场极化技术  

Electrical-Poling Technology of Lithium Tantalate for Quasi-Velocity-Matching Phase Modulator

作　　者：吕航[1] 陈险峰[1] 陈理军[1] 张军锋[1] 陈玉萍[1] 夏宇兴[1] 

机构地区：[1]上海交通大学物理系,上海200240

出　　处：《中国激光》2006年第3期371-375,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金(60477016;60407006);上海市重大基础研究(04DZ14001);上海市教委曙光计划合作资助项目

摘　　要：利用准速度匹配技术可以实现大调制度的电光相位调制器,从而可以用来展宽激光频谱,它在光谱学、激光变频以及改善激光均匀性等方面有重要应用。当大功率激光通过调制器时,要求晶体的通光面积越大越好,所以大面积并且具有较大厚度的铁电晶体的室温极化技术成为准速度匹配实现的关键技术。详细研究了大面积并且厚度达到1 mm的钽酸锂晶体的电场室温极化过程,针对在极化过程中外部施加高电压时产生的回流现象,采用了改变极化时间来抑制,取得了较好的效果。利用热释电和化学腐蚀方法,成功地实现了钽酸锂晶体的大面积畴反转。该种技术同样可以用于其他大面积铁电晶体的极化。Quasi velocity matching can be used to realize electron-optics phase modulator with high modulation index, which has essential applications in spectroscopy, laser frequency conversion and improving laser beam uniformity. When laser beam with high power propagates through the modulator, the larger aperture of the device is necessary, so the poling technology on ferroelectric crystal with large area and high-thickness is essential for high power quasi velocity matching. In this paper, the electrical-poling process in room temperature on LiTaO3 crystal with the thickness of lmm is studied in detail. In order to restrain back current during poling process, control of electrical poling time is adopted in the experiments, large-area domain inversion of LiTaO3 is successfully realized proved by thermoelectric effect and chemistry etching method. The proposed technology can be also employed in other ferroelectric crystal poling.

关 键 词：材料 电光调制 畴反转 室温电场极化 准速度匹配 

分 类 号：O737[理学—晶体学]