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How to observe a field patterns other than excited frequency

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Is it possible to observe field pattern other than the excited frequency. One smple experiment I am exciting a 500 nm width, 30 nm height Si waveguide at 193.42 THz with numeric port (boundary mode analysis study), am giving 193.42 THz at frequency domain, say I want to observe the field patterns at 300 or 200 THz, that means it will appear blank (no field since excited at 193.42 THz) . I can only see te field patterns at the excited ones (mean by frequency entered in the frequency domain, i.e., the excited ones), despite of giving a parametric sweep at other frequencies. So how to observe field patterns at different frequency other than the excited frequency?


1 Reply Last Post 15.05.2020, 21:21 GMT-4
Robert Koslover Certified Consultant

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Posted: 5 years ago 15.05.2020, 21:21 GMT-4

If you are doing a parametric sweep of frequency, and have configured the solver properly, then it will presumably step through, compute, and store the solutions at all of the frequencies listed in your parametric frequency sweep. You should then be able to access those solutions via the pull-down menus that are accessible via the various results plotting options. Now, if you are instead talking about something else, such as having a single "excitation" frequency while expecting to see some other frequencies being generated by means of physics interactions occurring within your structures/materials, then you are talking about a non-linear physics problem. In that case, you should probably not be trying to study this in the frequency domain at all, but should consider a time-domain model.

If that advice doesn't help, then I suggest you post your model to the forum so that others can take a closer look at it and can then provide more helpful and specific comments and advice. Good luck.

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Scientific Applications & Research Associates (SARA) Inc.
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If you are doing a parametric sweep of frequency, and have configured the solver properly, then it will presumably step through, compute, and store the solutions at *all* of the frequencies listed in your parametric frequency sweep. You should then be able to access those solutions via the pull-down menus that are accessible via the various results plotting options. Now, if you are instead talking about something else, such as having a *single* "excitation" frequency while expecting to see some *other* frequencies being generated by means of physics interactions occurring within your structures/materials, then you are talking about a *non-linear* physics problem. In that case, you should probably not be trying to study this *in the frequency domain* at all, but should consider a time-domain model. If that advice doesn't help, then I suggest you post your model to the forum so that others can take a closer look at it and can then provide more helpful and specific comments and advice. Good luck.

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