mode expansion monitor for a gaussian beam in air

- January 15, 2023 at 6:26 am
  
  Chris Chase
  Subscriber
  
  I want to launch a gaussian source from air to be incident on a freely suspended grating, and calculate overlap between reflection and launched gaussian source. I guess I need to use mode expansion monitor. How should I pick mode selection?
- January 16, 2023 at 5:53 pm
  
  Guilin Sun
  Ansys Employee
  
  Unfortunately, mode expansion monitor only works for waveguides. In your case, you will need to calculate the overlap with a monitor to get the reflection profile and the source fields after simulation. Please refer
  https://optics.ansys.com/hc/en-us/articles/360034396834-Understanding-the-mode-overlap-calculation
  /courses/index.php/courses/lumerical-fde-solver-physics/lessons/overlap-and-frequency-sweep-lesson-2/