Second harmonic generation in ferroelectric ceramic (Pb,La)(Zr,Ti)O3 under external electric field

• Main Authors: Yan-Chzu Lin, 林彥助
• Other Authors: Adam Y. Wu
• Format: Others
• Language: en_US
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/35726479806181856137

碩士 === 國立海洋大學 === 電機工程學系 === 89 === Abstract Nonlinear optical effects have drawn much research interest many people for the past thirty years. The main topic is how to improve the nonlinear optical susceptibility and the conversation efficiency of SHG in nonlinear materials. Many methods to enhance the nonlinearity have been reported. The methods include inventing new materials, applying external dc electric field, corona poling, and changing the temperature, etc. The ferroelectric material PLZT (9/65/35) ceramic has a character that in zero external electric field, it has a central-symmetric structure with a cubic structure and is optically isotropic, but when under an external electric field it becomes a noncentral-symmetric structure, with a tetragonal structure. By applying an electric field, PLZT becomes a nonlinear optical material and possesses ferroelectric property. It can be used for electrooptic devices applications. In this thesis, the experimental results were analyzed by using the Maker fringe technique. The method can be used for calculating the nonlinear optical susceptibility deff under different electric field. Our results show that the nonlinear optica susceptibility can be enhanced by applying dc electric field. So by applying an electric field and thus the intensity of SHG.