Dear Ammar,

The term normalized transmittance sounds a bit odd. Transmittance is, by default, normalized, as it is the ratio of output to input power. I downloaded the model from the blog and obtained the same spectrum as you. It looks like the target one divided by two, perhaps that’s what the author meant by “normalized”?

Best regards, Andrzej

Andrzej Gawlik yeah that's the issue! I tried with other structures also but apparently same issue persists there also which led me to think that maybe I'm doing something incorrect. I have attached a pdf showing the same issue with another structure from the paper. Can you please have a look at that maybe you'll find the discrepancy.

(1) I had the experience in 3-D photo-crystal block, however I do not know on 2D.

(2), (3) not in my experience.

Ammar Khan, your figures and those from the paper look qualitatively similar. The maxima are slightly shifted, but you are comparing different techniques. You used FEM simulations, whereas the authors of the paper used FDTD. In my experience, you won’t get exactly the same results with different methods, or even with the same method but different software versions.

Also, the authors used the term “normalized” transmittance without explaining what they meant. I suspect they normalized the spectra with respect to the one with the highest transmission.