Power Coupling Question

- August 2, 2021 at 8:03 am
  
  samishi
  Subscriber
  
  Hello,
  I am trying to compare the formula of coupling coefficient Kappa I'm using to the one Lumerical uses to compute the power coupling. I consulted the book referenced on this article (Optical Waveguide Theory):https://support.lumerical.com/hc/en-us/articles/360034925173-coupling-Script-command, but I am not sure which integral was used to calculate the coupling as there were many.
  Could someone please point out which part of the book has the expression of the power coupling or just the coupling?
  
  Thank you very much!
- August 4, 2021 at 12:32 pm
  
  Greg Baethge
  Ansys Employee
  
  Thank you for posting your question. I couldn't check the reference (we probably have a physical copy at the office, in Vancouver, but I can't access it as I'm based in UK), I think you will find some more information about the coupling calculation in the mode expansion monitor page. The coupling can be calculated from the complex transmission coefficients detailed in that page.