I want to simulate the coupling between a Guassian beam and a sandwich waveguide structure and the focus position should be adjusted along the Z-axis. I tried to use the User-Defined profiles but ddidn't succeed.
Malcolm White
I've no experience with the software, but I expect you need the beam waist at the point in the problem where it hits your sample, or in the middle of your sample. I expect the phase distribution is just the same as setting a far-field convergence angle towards the centre of the beam waist. The bigger the input aperture the smaller the beam waist can be and and/or the further from the input aperture it can be. It may be that you are asking for a beam waist that is too small, too far from an aperture that is also too small. The software may just not give an answer if you ask for that. Try making the input aperture larger and shortening the distance to the beam waist, and making the beam waist larger, then, when you have a combination that works, change one or two of them so that the other(s) can be adjusted back to what you want. The beam waist will never be less than half a wavelength across, even for very large apertures very close to the waist.
0 votes
0 thanks
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Optics
More Wenda Cui's questions See All
Similar questions and discussions