How to simulate a big Si3N4 ring resonator in varFDTD or FDTD

- June 4, 2024 at 11:20 pm
  
  Minming He
  Subscriber
  
  Hello,
  I am trying to simulate a Si3N4 based single bus ring resonator in varFDTD. The radius of the ring is 90um and the result was attached. I changed the parameters of the ring resonator. The result did not change too much, and just the magnitude of the oscilation changed. How can I see a normal transmittance of a ring resonator? Thank you!
- June 5, 2024 at 9:12 pm
  
  Amrita Pati
  Ansys Employee
  
  Hi Minming,
  It is hard to predict the reasons without actually having looked at the simulation file. Usually to confirm the validity of results, we recommend customers to perform convergence testing on different parameters. One of the main parameters, I would say is the mesh accuracy. Have you tried running the simulation for different mesh accuracies and compared the results? Is the screenshot that of transmission? I would recommend reducing the auto shutoff level of the varFDTD simulation (and run the simulation longer), looks like the transmission is going above 1.
  Regards,
  Amrita