Thanks for sharing the file. I had a look and there’s a couple of things that puzzle me:
- You are using a uniform mesh with mesh override regions, it is contradictory, as you have different mesh sizes defined. Mesh override regions can be used with the non-uniform mesh as it allows to set a finer mesh over specific areas.
- You set the simulation temperature to 77K. This will not affect the simulation unless you are using temperature dependent materials, as discussed here.
- You modified the minimum mesh step to a very small value (2.5e-6um). This setting is there to prevent the use of a unrealistic mesh that could lead to a very demanding calculation resources.
- The auto shutoff min was set to 1e-4 instead of 1e-5. This is to ensure the simulation runs enough so the fields decay enough by the time the simulation ends. If the simulation is too short (and the fields are still high), it can leads to some artefacts in the results.
That said, I’m not exactly sure what causes the error you had, but by using standard settings, the simulation ran without errors. I would suggest to start with the default settings and a coarse mesh and, once you are confident in the way the simulation is set, you can reduce the mesh size and eventually run a convergence test.