Hello Amit,
You will need to be a bit more clear regarding your request. Are you looking for information on how to design the ring resonator or just how to set it up in OptiFDTD?
You will find we have webinars that provide a good entry point for the design and analysis of 1D and 2D crystal structures with defects. You will find them on our YouTube channel (https://www.youtube.com/c/OPTIWAVEHD). There are three I would specifically recommend:
- Photonic Crystal & Band Gap Simulation – https://www.youtube.com/watch?v=t2XIE1eNXd4
- OptiFDTD Advanced Features – https://www.youtube.com/watch?v=irfbuPFcWD0&t=1514s
- OptiFDTD Advanced Applications I – https://www.youtube.com/watch?v=R8HZgqJ7bqs&t=1536s
Scott