Syahriar Ary
Department of Electrical Engineering, Faculty of Science and Technology, University Al Azhar Indonesia, Jakarta, Indonesia.
Sci Rep. 2025 Jan 8;15(1):1338. doi: 10.1038/s41598-024-84274-7.
Curvature of a dielectric waveguide always leads to attenuation of the mode power as it propagates through the curved region. In single mode guides, bending loss becomes significant as the radius of curvature reduces and is strongly dependent on the confinement of the guided mode, so that weakly guiding waveguides can tolerate only large radii of curvature. In this paper we verify our new theoretical version on power loss prediction of S-bend optical waveguides by using analytical theory based on integration of absorption coefficient and compare it to the experimental measurement of such waveguide bends. The objectives are to formulate the best analytical theory available that can predict the power loss in S-bends whose shape is defined as a function y = f(x), where its first derivative is continuous. Using this technique, the effect of post-process thermal annealing of channel guide devices fabricated by electron beam irradiation of silica PECVD materials is investigated. A particular performance characteristic is examined, which have its origin in the index reduction caused by annealing, increases in waveguide bend losses. Furthermore, to determine the waveguide shape, we used Marcatili's effective index method, employing model-dependent parameters obtained from the experimental data.
介质波导的曲率总会导致模式功率在通过弯曲区域传播时产生衰减。在单模波导中，随着曲率半径减小，弯曲损耗会变得显著，并且强烈依赖于导模的限制，因此弱导波导只能承受较大的曲率半径。在本文中，我们通过基于吸收系数积分的解析理论验证了关于S形光波导功率损耗预测的新理论版本，并将其与这种波导弯曲的实验测量结果进行比较。目的是制定出可用的最佳解析理论，以预测形状定义为函数y = f(x)（其一阶导数连续）的S形弯曲中的功率损耗。利用该技术，研究了通过对二氧化硅PECVD材料进行电子束辐照制造的沟道波导器件的后处理热退火效果。研究了一种特殊的性能特征，其源于退火导致的折射率降低以及波导弯曲损耗的增加。此外，为了确定波导形状，我们使用了马尔卡蒂利有效折射率方法，采用从实验数据中获得的与模型相关的参数。
