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Assign the material for background in RF module

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Hi all,

I am simulating an aperture in RF 3D module. I created a silicon ellipse lens and an aperture, and I wanted to see the far field beam passed through the aperture and the silicon lens. And I want to change the background material to Silicon too. I found the global material is the material valid throughout the model. But is this material also valid for the background (outside of the model)?

Hope someone can tell me how to do it. Thanks very much in advance!


2 Replies Last Post 28 nov. 2019, 05:05 UTC−5
Edgar J. Kaiser Certified Consultant

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Posted: 5 years ago 28 nov. 2019, 04:30 UTC−5

There is no material outside the model. You can only assign material within the model, i.e. within the meshed geometry. The far field is calculated at the inner boundary of a PML.

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Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
There is no material outside the model. You can only assign material within the model, i.e. within the meshed geometry. The far field is calculated at the inner boundary of a PML.

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Posted: 5 years ago 28 nov. 2019, 05:05 UTC−5

Dear Mr. Kaiser,

Thanks for your reply. In my model, I set the background field as a Gaussian beam with 30um beam waist, and I want to see the far-field beam of this beam passing through an aperture. However, my working wavelength is 80um. In this case, the paraxial approximation is not satisfied. That is the reason why I want to make the background to be silicon. So the beam will be much less divergent. I tried to increase the size of the silicon ellipsoid, but it's too large to compute.

I have attached the mph file below. Could you please help me to have a look and give me some advice?

Thanks a lot!

Dear Mr. Kaiser, Thanks for your reply. In my model, I set the background field as a Gaussian beam with 30um beam waist, and I want to see the far-field beam of this beam passing through an aperture. However, my working wavelength is 80um. In this case, the paraxial approximation is not satisfied. That is the reason why I want to make the background to be silicon. So the beam will be much less divergent. I tried to increase the size of the silicon ellipsoid, but it's too large to compute. I have attached the mph file below. Could you please help me to have a look and give me some advice? Thanks a lot!

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