Hi Sebastian,
There is no option for defining an elliptical cross section directly in OptiGrating. If you’re interested in simulating gratings in fibers with elliptical cross sections, one option would be to use OptiGrating’s “Other Waveguide” module. This requires you to provide the mode parameters, which you could evaluate using some other software, like OptiMode.
If adding an azimuthal dependence to the index modulation is sufficient for your purposes, you can do so in OptiGrating using the “azimuthal photosensitivity” parameter in the “Single Fiber Profile” menu. The azimuthal photosensitivity acts as an envelope function for the index modulation, and can be set as a user-provided function.
If you have questions about either of these options, please don’t hesitate to contact me directly at amine.abouzaid@optiwave.com
Amine
