Grating Solver Development Company
Deep Grating Example:
GSolver is numerically stable for very deep gratings. To illustrate this create a simple binary grating in Aluminum. (See the User's Manual for guidance.)
In this example I looked at the TE and TM polarization diffraction efficiency as a function grating (grove) depth. The aluminum substrate and 50% duty cycle aluminum grating had 800 lines/mm, 1 micron wavelength at 30 degrees incidence. 13 orders (total of 27) were retained.
The figure below shows the TE diffraction efficiency for a groove depth from 10 to 20 microns. This calculation could be extended to groove depths well beyond thousands of wavlengths without encountering numerical issues.
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This next figure shows the same calculation for the TM mode.
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