A Theoretical Description of Node-Aligned Resonant Waveguide Gratings

Waveguide gratings are used for applications such as guided-mode resonance filters and fiber-to-chip couplers. A waveguide grating typically consists of a stack single-mode slab grating. The filling factor the with respect to mode intensity profile can be altered via changing waveguide’s refractive index. As result, propagation length is slightly sensitive index changes. Here, we theoretically investigate whether this sensitivity increased by using alternative geometries. Using rigorous coupled-wave analysis (RCWA), factors modes supporting more than one simulated. It observed that both long lengths large sensitivities changes achieved nodes higher-order modes.