INTERCONNECT disconnected ports



The present behaviour for disconnected pins in INTERCONNECT is to have the light perfectly disappear (i.e., ideal PML). In reality, there would be reflections. Is there a way to have it automatically connect a specific component? e.g., S11 parameters for a 500 nm waveguide with an ending.

I know this would be specific to many things (waveguide specifics, what else there is, wavelength, polarization, etc). But a PDK could have this defined in it, namely one of the components in the CML would be a “disconnected” 1-port component.

Or maybe I could add this to a script that loads a SPICE file?

There is a check disconnect, but it only returns a warning in the script prompt output:

I don’t see how to access this via script, namely get a list of disconnected ports. If I had this, I could then attach my “disconnected” S11 component accordingly.

Finally, I could implement this in KLayout, in the SiEPIC_EBeam_PDK, namely where I add a “ebeam_disconnected_1550” component to each pin, but that would be a fair bit of work and specific to this PDK implementation.

Thank you



Hi @lukasc, thank you for raising this issue up. Currently we don’t have a script command that finds the disconnected ports in INTERCONNECT. I’ve passed this information to the R&D team, they will start investigate on this shortly. I will keep you updated about the progress :grinning:


I just implemented this on the KLayout side in the SiEPIC EBeam PDK

It adds the “disconnected” component, which I simulated in 3D FDTD, and is in the EBeam PDK. Then you can see the effect of reflections from the un-terminated 500x220 nm SOI waveguide.

Here’s an example of a ring resonator, with and without the disconnection. You can see the quality factor is affected.