Learning Forum

[Sept]

Hello,

I had a couple questions regarding the SSC simulation provided by lumerical.

The first question would be regarding the size of the port at the tapered end. I remember going through some instructional vidoes that reccomended the port sizing to be big enough where the E field intensity should not be below around -10 on the log scale (pictures attached).

With that said, it leads into my second question. Given that the mode at the tapered end is large at the boundaries, would PML boundaries given an advantage over metal boundaries for this type of simulation?

 

Any advice would be helpful.

 

[Ethan Keeler]

Hello, thank you for your questions and sharing your model screenshots! Based on what you shared, a PML boundary could be a good choice since there is a high reflection at metal boundaries.

However, I would consider instead expanding the simulation region if that is possible. If the evanescent fields of the mode interact with the boundary (either metal or PML), it can introduce artifacts into your simulation. Even a PML boundary can have a non-negligible reflection. Therefore, we generally recommend that the field intensity should be around 10^-10 at PML boundaries.