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Nano Optics - Single dipole near infinite interface

Posted Oct 29, 2012, 7:25 a.m. EDT Version 4.3 2 Replies

Jean-Christophe Lavocat
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I am trying to reproduce far field radiation patterns for single emitters close to an infinite dielectric interface. Namely, I place an emitter in air, in the vicinity of a glass substrate (10[nm] above). The dipole moment is oriented toward the interface.

I expect a far field angular pattern similar to the one attached (expected_behavior.jpg where they put the dipole in water instead of air). Instead I get something like the other picture (dipole_near_interface.png).

Light should be directed along the critical angle (in Air/Glass case -> 41 degrees). Instead of that, I find an extremum at around 50 degrees.

I define the dipole as a point dipole. I have PML, but I guess that have two different materials touching could be a problem here. Therefore i want to know if I am indeed limited to finite systems, or if I can model a dipole with two infinite materials .

Thanks for reading,
Jean-Christophe

ps : Model made with C.4.3
2 Replies Last Post Sep 1, 2014, 5:24 a.m. EDT
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Hello Jean-Christophe Lavocat

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Huan Hu
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Posted: 1 decade ago May 18, 2013, 2:00 a.m. EDT
Hi, I carefully read your model but I didn't found anything wrong... But when I tried a very similar model (electric dipole in vaccum and use a spherical layer as PML) I get a error as 'NaN or Inf found when solving linear system using SOR.' And sometimes pml can not work when there is a dipole (it's easy to see that in a 2d model). I guess that maybe related to your question and I wonder how you make it work with point dipole source and pml layer. Can you give me some advises?
Hi, I carefully read your model but I didn't found anything wrong... But when I tried a very similar model (electric dipole in vaccum and use a spherical layer as PML) I get a error as 'NaN or Inf found when solving linear system using SOR.' And sometimes pml can not work when there is a dipole (it's easy to see that in a 2d model). I guess that maybe related to your question and I wonder how you make it work with point dipole source and pml layer. Can you give me some advises?
Nitzan Livneh
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Posted: 1 decade ago Sep 1, 2014, 5:24 a.m. EDT
Hi,

The dipole orientation in the file you uploaded is (0,0,1). A dipole pointing to the Z direction will not radiate in the Z direction. In order to get the "expected behavior" just change the dipole orientation to any (x,y,0), (1,0,0) for example.
I'm sure it's no longer relevant for you, but for other people (like me) who are looking for advice, it might help.

Nitzan
Hi, The dipole orientation in the file you uploaded is (0,0,1). A dipole pointing to the Z direction will not radiate in the Z direction. In order to get the "expected behavior" just change the dipole orientation to any (x,y,0), (1,0,0) for example. I'm sure it's no longer relevant for you, but for other people (like me) who are looking for advice, it might help. Nitzan

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