Binary grating
We want to analyze a binary metallic grating, e.g. from paper: Li,
Haggans, "Convergence of the coupled-wave method for metallic
lamellar diffraction gratings," J. Opt. Soc. Am. A 10, 1184-1189 (1993).
It consist of a lamellar grating with a groove depth of 1 μm. The
dielectric has an optical index of 0.22-i*6.71. The incident wavelength
λ, the period Λ, and the height of the grating is 1 μm. The angle of
incidence is equal to 30º. The incident polarization is TM.
Firstly, we have to set the following parameters in the file
main.m as follows:
number_of_orders=41;
lambda=1;
use_dispersion=2; % 2= no dispersion
theta0=30;
polarization=1; % 1=TM polarization
grating=0; % 0=binary grating
Lambda=1;
thickness_total=1;
n1=1;
n3=0.22-6.71*1i;
ng=1;
nr=n3;
duty_cycle=.5;
shift=.5;
measurement=0; % 0=shows all diffraction efficiencies
We obtain this result:
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