As. Bonnetbendhia et F. Starling, GUIDED-WAVES BY ELECTROMAGNETIC GRATINGS AND NONUNIQUENESS EXAMPLES FOR THE DIFFRACTION PROBLEM, Mathematical methods in the applied sciences, 17(5), 1994, pp. 305-338
We consider the two-dimensional scalar problem of the diffraction of a
plane wave by an infinite grating of conducting bodies immersed in a
periodical dielectric medium. A Fredholm-type formulation is derived a
nd studied. The existence of a solution is proved and some uniqueness
results are established. A detailed description of the guided modes of
the grating is carried out. Finally, various non-uniqueness examples
for the diffraction problem are exhibited.