I designed double slit experiment using RF module in COMSOL and tried to get interference patter, The results are following with 930MHz frequency.
What do you predict from the pattern?
Looking at your picture is seems to me that your slots are half a wavelength apart. If that is so, then you should see a peak at 0 degrees (directly ahead), and nulls at +/-90 degrees. This is what you seem to be getting. Your slots are too close together to see a convincing interference pattern with several peaks and troughs. One wavelength apart would be a start, but you need the slots to be several wavelengths apart, like 2 or even 4 wavelengths, to see more peaks. The pattern will not be in the final form until the wave is 8 wavelengths from the slots if they are 2 wavelengths apart, or 32 wavelengths from the slot if they are 4 wavelengths apart. If the slots are 1 wavelength apart you would expect to see nulls at +/-30 degrees and peaks at 0 degrees and +/-90 degrees and the size of your simulation is probably big enough.
What you see is exactly what you should expect, if your your experiment had been designed. It appears that you may not have worked out what your slot spacing should have been before you started.
Hello Tanasam Shaheen ,
Malcolm White is right, the slits are too close (compare to the wavelength) this is why you don't see clear interference.
If you put smaller wavelength, you may see some interference.
The wavelength corresponding to your simulation is 0.322 m. I guess that your scale is in meter. The distance between your slits is in the same order as the wavelength.
Can you please plot the Poynting vector flux distribution : sqrt(emw.Poavx^2+emw.Poavy^2+emw.Poavz^2) ?
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