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Scattering boundary condition and port with plane wave

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Dear all,

I want to simulate the periodic nanostuctures on silicon. now i am using comsol 4.3a version which is not supported PML with port boundary. for that i need to define the Scattering boundary condition at the port and also how to calculate the Reflection and transmittance for port.

some body help me how to implement both scattering boundary condition at the port.

Thanks

4 Replies Last Post 2013年8月9日 GMT-4 23:57

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Posted: 1 decade ago 2013年5月23日 GMT-4 17:07
Hi Syer.

Are you doing this simulation in a time domain study? You can only define a port in time domain simulation by setting a scaterring boundary condition and specify the E0 in time.

If you are doing in a frequency domain study the two ports can be specify and the reflection coefficient are automatic computed by comsol. If you want a passive port (exit of the waveguide), you just select a port with zero input power.

Are you imposing a TM00 boundary condition in the port?

Kind Regards,

dudu
Hi Syer. Are you doing this simulation in a time domain study? You can only define a port in time domain simulation by setting a scaterring boundary condition and specify the E0 in time. If you are doing in a frequency domain study the two ports can be specify and the reflection coefficient are automatic computed by comsol. If you want a passive port (exit of the waveguide), you just select a port with zero input power. Are you imposing a TM00 boundary condition in the port? Kind Regards, dudu

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Posted: 1 decade ago 2013年5月25日 GMT-4 00:16
Hi Dudu,

I am using a plane TM polarized wave at the port boundary in the frequency domain. I am using comsol 4.3a version which PML at port not supported for that i need to define the Scattering boundary condition for take care PML condition at the port. Now my question is how will i define port with plane wave in TM or(TE ) Mode and same time scattering boundary condition at the port boundary.


Thanks

Hi Dudu, I am using a plane TM polarized wave at the port boundary in the frequency domain. I am using comsol 4.3a version which PML at port not supported for that i need to define the Scattering boundary condition for take care PML condition at the port. Now my question is how will i define port with plane wave in TM or(TE ) Mode and same time scattering boundary condition at the port boundary. Thanks

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Posted: 1 decade ago 2013年5月31日 GMT-4 19:38
Hi Syed,

I have managed to produce a plane wave in a periodic structure using two ports. In the port definition use: user defined with magnetic field imposition (or electric) in a direction parallel to the port and input the propagation constant. The propagation const in vacuum is 2*pi*freq/c.

Using the port boundary condition allows you to compute the reflection and transmittance. The scattering b.c. doesn't.

I am having a problem with this simulation only for small dimensions. It works fine in the mm scale or above but it doesn't converge in the um scale or bellow. Have you experienced this problem as well?
Hi Syed, I have managed to produce a plane wave in a periodic structure using two ports. In the port definition use: user defined with magnetic field imposition (or electric) in a direction parallel to the port and input the propagation constant. The propagation const in vacuum is 2*pi*freq/c. Using the port boundary condition allows you to compute the reflection and transmittance. The scattering b.c. doesn't. I am having a problem with this simulation only for small dimensions. It works fine in the mm scale or above but it doesn't converge in the um scale or bellow. Have you experienced this problem as well?

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Posted: 1 decade ago 2013年8月9日 GMT-4 23:57
Hello Ricardo,

Have you solved this problem? I am having the same problem now. Thank you.
Hello Ricardo, Have you solved this problem? I am having the same problem now. Thank you.

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