Simulation of high-order DFB laser in Interconnect

- April 25, 2023 at 12:16 am
  
  ssaei014
  Subscriber
  
  Hi, I'm designing a DFB laser using TWLM model in Interconnect. For the first-order grating, I set the period equal to ~200 nm and get very good results:
  I want to see the result of a third-order grating, meaning the pitch is now ~600 nm. I'm expecting to see a single-mode behaviour just like above, with maybe smaller SMSR. But the result is as below:
  It doesn't see the grating and acts as a FP laser. How can I make sure high-order DFB is defined properly in Interconnect?
- April 27, 2023 at 10:04 pm
  
  GWANG
  Ansys Employee
  
  Hi ssaei014,
  
  At a glance, I think the approach you are using is correct. This looks to me to be a gain or grating transmission problem. Could you please contact support through email and share the file there? We can follow up the discussion there. Thank you.