Guilin Sun
Ansys Employee

Passive circuit design involves mode analysis (FDE), propgation (EME, varFDTD and FDTD), as well as INTERCONNECT. Please refer those examples: https://optics.ansys.com/hc/en-us and click  Photonic Integrated Circuits - Passive

For active circuit design, CHARGE and HEAT solvers may be needed. Please click  Photonic Integrated Circuits - Active

On the same page you can click each solver for more information.

There are also some 100-level videos: https://www.lumerical.com/search/?q=videos 

Please have a look. Some may need you to log in as a customer.