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Problem when simulating nanowire absorption

Posted 24.05.2011, 04:27 GMT-4 RF & Microwave Engineering, Studies & Solvers 4 Replies

Olivier Demichel
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Hy all,

I'm simulating the absorption of a nanowire in vaccum. I started with a 2D model in the RF module. My geometry is a nanowire in vacuum surrounded by cartesian air-PML. I solved the problem for the scattered field. The incident field propagates along the y direction and is either x or z polarized.

I have no problem with the x-polarization, however when I solve the problem for the z-polarized field, the scattered field is not well absorbed by the PML (see fig in attachment) and it does not change if I increase the size of the PML and/or the mesh size.

Can somebody explain why ?

Furthermore, I'm trying to simulate the absorption in the 3D geometry and to reduce the model size, I want to model only a quarter of a nanowire, which boundary condition should be apply ? I found that perfect electric/magnetic BC are not rigorously correct in that case. Is there a way to impose different BCs on each component of the fields on the surface ?

Thanks a lot !

Olivier
4 Replies Last Post 24.10.2016, 04:01 GMT-4
Shakeeb Bin Hasan
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Posted: 1 decade ago 27.05.2011, 08:35 GMT-4
I cannot say if this will completely eliminate your problem, but your PMLs don't seem to be properly drawn. I would suggest you to have a look at the tutorial model "Dielectric scattering" in which they do exactly what you are trying to do here.

All the best
I cannot say if this will completely eliminate your problem, but your PMLs don't seem to be properly drawn. I would suggest you to have a look at the tutorial model "Dielectric scattering" in which they do exactly what you are trying to do here. All the best
Tom Celano
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Posted: 1 decade ago 17.06.2011, 13:19 GMT-4
I found that having the PMLs intersect eachother on the outside surface works well, you could also try putting a scattering boundary on the outside of each of the PMLs. I am also trying to model nanowire absorption and I was wondering what you were using to induce the electric field down the sample. I tried using a scattering boundary but this requires an open face without a PML, and for some reason when I tried using a port at the inner face of a PML it did not work.

Hope this helps.
I found that having the PMLs intersect eachother on the outside surface works well, you could also try putting a scattering boundary on the outside of each of the PMLs. I am also trying to model nanowire absorption and I was wondering what you were using to induce the electric field down the sample. I tried using a scattering boundary but this requires an open face without a PML, and for some reason when I tried using a port at the inner face of a PML it did not work. Hope this helps.
Olivier Demichel
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Posted: 1 decade ago 18.06.2011, 03:57 GMT-4
Hey Tom,
you just have to use the "solve for scattered field" mode in the settings of the emw physics. This will allow you to define an incident electric field in the non-pml regions.
have fun
Olivier
Hey Tom, you just have to use the "solve for scattered field" mode in the settings of the emw physics. This will allow you to define an incident electric field in the non-pml regions. have fun Olivier
M.H.Elshorbagy
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Posted: 8 years ago 24.10.2016, 04:01 GMT-4
Hi Olivier

Could you please tell me how to set x polarization in 2D

Thanks in advance

M.H.Elshorbagy
Hi Olivier Could you please tell me how to set x polarization in 2D Thanks in advance M.H.Elshorbagy

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