EIA: The Effect of Hydrogen on Optical Damage in Ti DiffusedLiNbO3 Waveguides

这项工作是作为一个工程启动奖（EIA）资助。 已经发现，氢在碳酸锂晶体中的存在， 使Ti扩散波导对光折射光学不太敏感 损害 这个项目旨在了解氢是如何 添加物降低损伤。 这项工作将分五个阶段进行：（1） 在受控气体环境中的高温退火将是 用于平衡（氧，锂和水的活动将是 同时控制）;（2）FTIR、拉曼和光学光谱 将用于分析平衡的晶体;（3）本体 光折变效应将通过写入全息图来测量 衍射光栅;（4）平面波导将由内扩散 （5）测量波导中的光学损伤。 这些步骤的结果将相互关联，以了解 氢缺陷的存在及其影响。 更好的 对锂酸盐中的氢的理解将允许制造 波导具有更长的寿命和更高的功率传输能力。 本提案描述了将进一步描述 光折变效应的研究 达成的谅解 在拟议的研究中， 装置. 这项研究的主要目标是识别氢 可能存在于碳酸锂中的相关缺陷，以及 以评估它们对光折射的正面或负面影响， 效果鉴定将通过研究晶体来进行， 在严格控制的环境中保持平衡。

This work is funded as an Engineering Initiation Award (EIA). The presence of hydrogen in lithium niobate crystals has been found to make Ti-diffused waveguides less susceptible to photorefractive optical damage. This project is aimed at understanding how the hydrogen additions lower damage. The work will proceed in five stages: (1) Annealing at high temperature in a controlled gas environment will be used for equilibration (oxygen, lithium, and water activities will be controlled simultaneously); (2) FTIR, Raman, and optical spectroscopies will be used to analyze the equilibrated crystals; (3) the bulk photorefractive effect will be measured by writing holographic diffraction gratings; (4) planar waveguides will be made by in-diffusion of titanium; and (5) optical damage in the waveguides will be measured. The results of each of these steps will be correlated to understand what hydrogen defects are present and what their effects are. A better understanding of hydrogen in lithium niobate will allow fabrication of waveguides with longer life and higher power transmission capabilities. This proposal describes work which will further characterize the photorefractive effect in lithium niobate. The understanding obtained in the proposed study should allow the fabrication of improved optical devices. The major thrusts of this study will be to identify hydrogen related defects which are likely to be present in lithium niobate, and to assess their positive or negative effects on the photorefractive effect. The identifications will be made by studying crystals which have been equilibrated in carefully controlled environments.