This is a short post just for sharing an example of setting up for resonant waveguide grating with Zemax RCWA.
We will use the data in this paper: https://onlinelibrary.wiley.com/doi/10.1002/lpor.201800017
In attached file, a grating is set up, following the paper, as shown below. The grating parameters are as below.
Period = 0.4 µm
Duty cycle = 0.5
index of substrate = 1.6
index of superstrate = 1.0
index of the grating = 1.7
thickness of lower part = 0.3 µm
thickness of upper part (binary grating) = 0.05 µm
![](https://uploads-us-west-2.insided.com/zemax-en/attachment/b2468220-1941-4e42-ba20-6a1597252a12.png)
We then intput a ray with TE polarization and 15 degrees incident angle with wavelength scanning between 0.546 µm ~ 0.552 µm.
By observing the 0 order reflection ray, the result is as below. This matches to the Figure 8 in the paper.
![](https://uploads-us-west-2.insided.com/zemax-en/attachment/77338c03-4307-4fc5-80b7-452a2ebf4523.png)
People can change the thickness of upper part of the grating to 0.025 µm and 0.1 µm to also check the result in the Figure 8 in the paper.
Have fun!