Mode expansion monitor error

- December 26, 2022 at 2:12 pm
  
  sudharsanan srinivasan
  Subscriber
  
  I am trying to edit the Lumerical file for Y-branch optimization using PSO. I just replaced the splitter section with a spline bend. The field simulation seems to run fine except I am receiving an Error: "Error: prompt line 1: Can not find result 'expansion for out' in the result provider 'modeExpout'". This error seems to occur regardless of where the monitor is placed, like say in the case when it is next to the source. Please advice.
- December 27, 2022 at 5:59 pm
  
  Guilin Sun
  Ansys Employee
  
  Do you mean this example https://optics.ansys.com/hc/en-us/articles/360042800353-Y-branch ?
  How did you specify "expansion for out"? did you use port result, or have power monitor and expansion monitor? did you choose the mode to be decomposed and have the variable name to output the decomposed result?
  
  Please check every step, and make sure the sweep can pick up the decomposed result, with proper settings. If you still cannot resolve this, please give screenshots for all related objects so we can know where is wrong.
- December 28, 2022 at 5:48 am
  
  sudharsanan srinivasan
  Subscriber
  
  This is the example I downloaded. https://optics.ansys.com/hc/en-us/articles/360042800333
  I did not change anything from the original file except the geometry. The original example runs well. Some screen shots are attached.
- December 28, 2022 at 5:09 pm
  
  Guilin Sun
  Ansys Employee
  
  If you only modify the geometry, you may need to recalculate the mode in expansion monitor. Please visualize the mode profile,and make sure it is normal. In addition, please visualize the fields in monitor "out".
  Make sure the mode expansion monitor and the DFT monitor are in the same waveguide. better at the same location.
- December 29, 2022 at 5:32 am
  
  sudharsanan srinivasan
  Subscriber
  
  Yes, I have taken care of all your tips, no luck.
- December 29, 2022 at 4:59 pm
  
  Guilin Sun
  Ansys Employee
  
  This may indicate that something has been changed. I would suggest that you download the example again, first run it to confirm everything is ok. Then modify the structure. Before running, reselect the modes and make sure they have updated. Other than the above suggestion, the forum may not be able to help further. If you have premium support, please send us email with simulation file attached.