Bruck Roman, Hainberger Rainer
AIT Austrian Institute of Technology GmbH, Health and Environment Department, Nano Systems, Donau-City-Strasse 1, 1220 Vienna, Austria.
Appl Opt. 2010 Apr 1;49(10):1972-8. doi: 10.1364/AO.49.001972.
The effect of a thin high-index coating deposited on polyimide waveguide grating couplers was investigated. A comprehensive numerical study was performed using an efficient simulation tool based on a Floquet-Bloch algorithm, and the results of this study were compared with experimentally obtained values for input coupling efficiencies. The application of a high-index coating permits efficient coupling from narrow beams even in material systems with a low index difference. This not only facilitates a denser integration of grating couplers but also permits low-loss lateral tapering to single-mode waveguides.
研究了沉积在聚酰亚胺波导光栅耦合器上的薄高折射率涂层的效果。使用基于弗洛凯 - 布洛赫算法的高效模拟工具进行了全面的数值研究，并将该研究结果与输入耦合效率的实验值进行了比较。高折射率涂层的应用即使在折射率差低的材料系统中也能实现窄光束的高效耦合。这不仅有助于光栅耦合器的更密集集成，还允许向单模波导进行低损耗横向变窄。
