Hello there,
I am trying to get a linear, dipole-like source in a circular cavity, taking advantage of cylindrical coordinates. I am looking for the best way to do that and encountered two problems, with the linearity of the source and positioning. First, I assumed that to get a linear point like source I need two sources Er and Ephi 90 degrees out of phase, but simulating a quick, 2D case of a source in free space and comparing emission patterns (Er, Ephi, Ez) it doesn't look the case - the best way to do that seems to be addition of m=+1 and m=-1 simulations with Er source only. While it solves the problem for flux monitors (simply adding fluxes) I am not sure if the LDOS and Harminv are affected in any way, would it be enough to take results for only one simulation? Secondly, my source should ideally lie in the middle of the simulation area, so r=0. From looking at spectrum from a broadband source in such scenario, it looks completely wrong, with several steep peaks, not a smooth Gaussian-like distribution. This problem disappears if the source is placed a bit off the center, but that, as I assume, results in a more ring-like source and the electrical field patterns are no longer correct. I tried placing it in the center and giving it a bigger size and got a combination of these two cases - a Gaussian like shape with a few protruding peaks. I guess it is some effect from having a source at the edge of simulation area, but is there any way to get around it? Best wishes, Dominika
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