Linearly Polarized (LP) modes

Hi all,

I'm willing to calculate linearly polarized modes, that is, modes with
only four non-zero components and azimuthal symmetry in a multimode
optical fiber (see for example www.rp-photonics.com/lp_modes.html ).

By using the mode analysis study I get to compute the first two LP0m
modes (I'm specially interested in modes LP01, LP02, LP03....).
Although, I have to compute more than 10 modes to get LP01 and LP02
modes. I have incremented drastically the number of modes computed but
I'm not able to get to the LP03 mode.

I wonder if there is a way I can "force" the results to have (for
example) Ex=0 and Hy=0 ?
Or even better, to force the resulting fields to have azimuthal symmetry?

A suggestion from the support staff is to restrict to a subset of solutions modeling a slice of the fiber's cross section (see file attached). Unfortunately, with this approach I'm only able to reproduce doughnut type fields (mixtures of TEM modes), but not the LP modes I'm looking for.

As you can see all the solutions have null electric field at the center of the fiber, while LP01, LP02 and LP03 have a maximum field at that point.

Thanks in advance.
Best,
--
Felipe BM