Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
How to visualize or calculate scattering of IR light on periodic metastructures?
Posted 09.03.2022, 16:40 GMT-5 Ray Optics, RF & Microwave Engineering, Wave Optics 3 Replies
Please login with a confirmed email address before reporting spam
Is it possible to calculate or visualize light scattering after interacting with a periodic structure?
I am using the RF module to simulate the incoming IR light onto a structure with microfeatures and have applied the Floquet boundary conditions on the sides. I would like to measure or visualize the scattering of light once the IR light interacts with the microfeatures.
I came across the following tutorial but it is geared towards gratings as opposed to different shapes of microfeatures:
https://www.comsol.com/model/diffraction-grating-19083
Any advice would be greatly appreciated!
Please login with a confirmed email address before reporting spam
What do you want to calculate exactly? In an infinitely periodic structure like the one you described the reflected angle is always emposed by your port boundary conditions. If you want to simulate the scattering off of a larger structure in multiple directions you need to simulate a larger structure. or at least a floquet port that supports multiple modes.
Please login with a confirmed email address before reporting spam
What do you want to calculate exactly? In an infinitely periodic structure like the one you described the reflected angle is always emposed by your port boundary conditions. If you want to simulate the scattering off of a larger structure in multiple directions you need to simulate a larger structure. or at least a floquet port that supports multiple modes.
Thank you for writing. I want to see if there is a way to visualize light rays interacting with a unit cell containing microfeatures. Or if it is possible, how to measure how much light is scattered from normal incidence after interacting with the geometry. An example geometry is shown in the attached image (source: https://www.youtube.com/watch?v=Wj1v-9-Ak_8).
Attachments:
Please login with a confirmed email address before reporting spam
What do you want to calculate exactly? In an infinitely periodic structure like the one you described the reflected angle is always emposed by your port boundary conditions. If you want to simulate the scattering off of a larger structure in multiple directions you need to simulate a larger structure. or at least a floquet port that supports multiple modes.
Thank you for writing. I want to see if there is a way to visualize light rays interacting with a unit cell containing microfeatures. Or if it is possible, how to measure how much light is scattered from normal incidence after interacting with the geometry. An example geometry is shown in the attached image (source: https://www.youtube.com/watch?v=Wj1v-9-Ak_8).
One you have microstructures you can't really speak of light rays. I am still not sure what you mean by 'how much light scatteres from normal incidence'. If the structure is sub-wavelength all you will get is a reflection and transmission coefficient. There are plenty of tutorial that calculate this so I don't think this is what you mean. The reflection coefficient of a conducting structure will be 1 with some phase shift.
if you mean scattering in different directions you have to expose a larger area. You have to possibly include the diffraction orders or expose it with a gaussian beam or ambient field and calculate the far field pattern.