Focusing of field

[huangtingying]

Hello,
I want to ask if this RCWA can calculate the focused field instead of the diffracted field?

[kch3782]

Is it correct that you asked if this RCWA is possible to calculate the field using the perfectly matched layer (PML) boundary condition instead of the periodic condition? Or do you mean something else?

[huangtingying]

I read a literature review the other day

Review The use of plasmonics in light beaming and focusing
The-use-of-plasmonics-in-light-beaming-and-f_2010_Progress-in-Quantum-Electr.pdf

It was written by Byoungho Lee. The fourth chapter mentioned Beam focusing by surface plasma polarities. The paper mentioned in this overview uses RCWA to calculate the focusing field, which was also written by Byoungho Lee.

Then I found that the author of the TORCWA also has Byoungho Lee, so I would like to ask whether the TORCWA can implement the functions mentioned in the previous paper of Byoungho Lee

[kch3782]

The presented figure was performed using the RCWA simulation, but it was performed using a perfectly matched layer (PML) boundary condition. RCWA basically operates under periodic boundary condition, and additional structure must be implemented to operate under PML boundary condition. (There is a formula in H. Kim et al., Fourier modal method and its applications in computational nanophotonics (2012)) Unfortunately, TORCWA currently doesn't have a function to create a structure for such a PML boundary.

Therefore, if you want the simulation like presented figure using TORCWA,

1. Directly implements the function that makes the PML boundary condition in the referenced book, or
2. Increasing the period to reduce the periodic effect, but it is less accurate and takes longer time to calculate.

Thank you.

[huangtingying]

Thank you very much