Ansys Learning Forum Forums Discuss Simulation Photonics Absorption in FDTD two methods different results Reply To: Absorption in FDTD two methods different results

sagar
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The reflection monitor should be above the source. Another suggestion is to keep the PML at least lambda (wavelength) spacing from the top or bottom surface of the structure. The way you have placed the monitor for reflection is basically calculating the (source power - reflection), in the forward direction it is recording the actual injected power coming from the source and in the backwards direction it is calculating reflection and the result is giving as (source power - reflection), which you are thinking as reflection. 

Place the monitor before the plane wave source, you should get 55.5% reflection and 18.5% transmission.

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