Setting up a simple angle-of-incidence electromagnetic 2D simulation

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Hello,

I am currently trying to figure out how to set up a basic electromagnetic wave propagation experiment hitting a sample at some angle of incidence. The module I'm using is Wave Optics at the Frequency Domain, and I'm looking into 2D simulations.

To just test out the waters, I'm trying to simulate a very simple setup with just a single rectangle of air. I have two ports on the top and bottom of the setup, the top being the excitation port. I'm trying to make the two boundaries on the sides to be PMLs and not periodic BCs. I suppose I should use the Scattering Boundary Conditions, but I am not quite sure how to specify the parameters of it.

My question is: How should I specify the excitation port to produce a propagating plane wave at an angle of incidence? I've been trying to play around the the propgation constant parameter and manipulate the electric field amplitude to be angle-dependent in the proper way, but all it has caused are weird electric field patters that don't resemble a simple propagation at an angle. I may be glossing over another parameter which I must work with, but I am not sure how to take it from there.

I believe I have succeeded perforiming something similar in 3D, since it has the option to setup the pitch-yaw-roll angle of the k-vector. However, I did not see something like that in 2D.

I appreciate any help in advance that could shed some light into the right direction (pun totally intended).

Thank you.


2 Replies Last Post Dec 2, 2019, 10:02 PM EST

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Posted: 5 days ago Dec 2, 2019, 3:37 PM EST
Updated: 5 days ago Dec 2, 2019, 10:37 AM EST

Consider using the wave-scattering formalism, instead of ports. You can specify the components of the incident wave. See the attached screen shot for where to do that.

Consider using the *wave-scattering formalism*, instead of ports. You can specify the components of the incident wave. See the attached screen shot for where to do that.


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Posted: 5 days ago Dec 2, 2019, 10:02 PM EST
Updated: 5 days ago Dec 2, 2019, 5:05 PM EST

Hi,

Thank you for your help! I've tried to go down this route to see if it works. I've disabled both ports, and specified all sides to be Scattering Boundary Conditions. However, I believe that it still behaves oddly. I've attached a picture of my wave-scattering settings. I've also attached the results of the electric field pattern for normal incidence (alpha = 0), and oblique incidence (alpha = 30 degrees, approproately converted to radians). The normal incidence seems (somewhat) plausible, but I'm not quite sure about the oblique case.

My thought process was to manipulate the components of the background electric field to depend on the angle in a way that the wave will propagate normal to the electric field. Am I on track?

Thanks!

Hi, Thank you for your help! I've tried to go down this route to see if it works. I've disabled both ports, and specified all sides to be Scattering Boundary Conditions. However, I believe that it still behaves oddly. I've attached a picture of my wave-scattering settings. I've also attached the results of the electric field pattern for normal incidence (alpha = 0), and oblique incidence (alpha = 30 degrees, approproately converted to radians). The normal incidence seems (somewhat) plausible, but I'm not quite sure about the oblique case. My thought process was to manipulate the components of the background electric field to depend on the angle in a way that the wave will propagate normal to the electric field. Am I on track? Thanks!

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