I’m PhD student and is currently using FDTD to solve for a light absorption problem. The geometry of simulation looks like this: a gauss source (633nm) falls on a TiN cube. I used the analysis group Pabs_adv to determine the power absorbed by cube. The cube lies on a silicon substrate. Area of source is 8 um* 8 um. The beam is focused on the edge of the cube for better excitation of plasmons. I want to use focused lens (N.A. 0.7) and for that I have to use “thin lens”. Here you write that for this you need to enable the function “fill lens”: Boundary conditions for focusing source
And I have a question: Why, when I enable “fill lens” , the absorption becomes more than without it? But with “fill lens” when this is observed diffractionIs. It possible to do without “fill lens”? And can I use “scalar approximation”, but chose waist radius which matches NA 0.7 ?
I have attached the FDTD file with my simulation.
Thanks in advance!
TiN 100nm NA0,7 2.fsp (290.3 KB)