This is for sure. Please refer to this article: https://optics.ansys.com/hc/en-us/articles/360034915753-Tips-for-accurately-measuring-reflection-in-an-FDTD-simulation
I guess there are some discrapancies in some properties between experiment and simulation. As mentioned in the forum post I shared with you, it can be more challenge to compare the experiment, since there are somgthing people do not know exactly.
FDTD solves Maxwell Equations so it will count all coherence physics.
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