Development of Highly Efficient, Visible Coherent Light Sources Using Semiconductor Lasers and Organic Nomlinear Optical Materials

在许多光电应用中，如显示器，迫切需要发射短波长的紧凑相干光源。记录和图像处理。光学二次谐波产生（SHG）使用有机材料作为有源介质和半导体激光器作为光源似乎是一个特别有吸引力的方法，因为已知一些有机材料表现出非常大的二阶光学非线性。这项研究是为了探索新材料和开发实现高效的基础技术而进行的。由有机材料和半导体激光器组成的波导型SHG器件。用CNDO/S方法对许多有机分子和晶体进行了非极化率和二阶极化率的理论计算。得到了与现有实验数据相当一致的结果。提出了一种改进的maker条纹法测量光学非线性；低功率（单模或多模）连续波半导体激光器作为光源与光电倍增管探测系统相结合。由于输入辐射的单模特性而产生的新效应已经被发现。对MNA、DAN和MBANP晶体的线性和非线性光学性质进行了表征。这些已被发现是有前途的SHG器件材料。以切伦科夫辐射的形式在MNA晶体的片状波导中观察到高效SHG。已经开发了控制板坯结构中晶体取向的方法。

compact coherent light sources emitting at short wavelengths are badly needed in many optoelectronic applications such as displays. recording and image processing. Optical second harmonic generation (SHG) using organic materials as active media and semiconductor lasers as light sources seems-to oe a particularly attractive approach because some organic materials are known to exhibit remarkably large second-order optical nonlinearities. This research has been conducted to explore new materials and develop basic technologies for realizing efficient. waveguide-type SHG devices comprising organic materials and semiconductor lasers.1. Molecular nvperpolarizabilities and second-order susceptibilities have been theoretically calculated for a number of organic molecules and crystals using a CNDO/S method. Reasonably good agrement with existing experimental data have consistently been obtained.2. A modified Maker-fringe method has been developed for measuring optical monlinearities; low power (single- or multi-mode) cw semiconductor lasers are used as light sources in combination with a photomultipliar detection system. New effects arising from single-mode nature of the input radiation have been discovered.3. Linear and nonlinear optical properties have been characterized for MNA, DAN and MBANP crystals. These have been found to be promising materials for SHG devices.4. Efficient SHG in the form of Cerenkov rediation has been observed form a slad waveguide of MNA crystal. Methods have been developed for controlling crytal orientaion in the slab configuration.