Hello @fgomez ,
After going through the entire processes my study follows as …
1.my simulation set up is a CoFeB thin film about 40 nm on thick (say 5~10 um ) SiO2 with a plane wave source angled at 45 degrees.
2. I investigated the R,T as a function of the incident angle of the source and thereby noticed that it will change but my interested wavelength is (say) 600nm.
3. Since I am using the angled source, I used the Bloch BCs in the direction of the E-Field plane of oscillation (Blue arrows of the source) and others are chosen as PML and this is continued all the while even though the polarization is changed.
4. Also, the incident angle of the source changes with respect to the wavelength of the broadband source, so I investigated the series of simulations which keep the angle fixed throughout the spectrum of the source and succeeded.
5. Besides that, I investigated with BFAST source and found the result is fitting my expectations. But the point where struck is I need the R,T as a function of mesh accuracy ( which I can get by running different simulations) for the respective structure. This R,T changes if I change the thickness of the SiO2 and FDTD area. So I want to know the perfect thickness to be inserted and meshing the very thin CoFeB using the mesh override and thick SiO2 in a normal manner needs a confirmation that it is acceptable. In other words, the convergence as a function of mesh accuracy as shown in here. testing the convergence
6. I calculated that using the method similar to the above example but found the max error of the R,T is getting away but not getting closer. I feel that if it is like that means convergence is not good by virtue of numerical dispersion. Is that right? or do I need to understand something in a different manner?
I see the script used in the convergence testing uses the stackrt code and it compares the analytical and simulation results. but what is the error means physically there and the maximum difference between the R, T Vs accuracy slider?
there is another example using TFSF source for the periodic structure which can check convergence as a function of mesh accuracy as shown in TFSF_convergence. But this is not suitable for me as you and @aya_zaki said previously. so no need to consider this example for convergence checking.
I apologize you if you feel that you already answered this in a different manner. But the complexity of my investigation led me to make this discussion.
Hope I explained well about my problem and in a simple sentence, how the convergence as a function of mesh accuracy is confirmed for meshing a particular thickness of the thin film deposited on a thick substrate with the above conditions? How to understand the max difference Vs slider value as shown in here