Hi all,
I am working on an eigenfrequency study on a 3D optical disk resontor. My resonator is a 3-layer structure with refractive index of 3.4/3.5/3.4 from top to bottom. What I found is that when I change the surrounding environment refractive index from 1 to 1.1, the quality factor for the same mode drops a lot, like from 23000 to 6800. I was surprised at the result and suspect this is caused by some numerical defects.
I searched eigenfrequecy around 286** THz. I set the mesh size in all of the region smaller than freespace wavelength/((refractive index)5) and I think the mesh is OK. I tried both scattering boundary condition and PML, and they gave me similar results. Could any one comment on this problem or give me some advice on how to get reliable quality factor?
I will really appreciate your help. Thanks!