I have been trying to simulate optical logic gates using COMSOL 5.6 software.

I have been trying to replicate the results of this article in order to learn the simulation method. Here is the link: https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=plasmonic+logic+gate+MIM+waveguide+comsol&btnG=#d=gs_qabs&t=1690146508321&u=%23p%3DliJIXWt-D1oJ

I have added ewfd and boundary mode analysis as study and I have added the input and output ports as well. But I am not sure if my approach is correct and I am not sure how to setup the boundary mode analysis.

Therefore I seek guideline and help for simulating optical logic gates. Thank you in advance.