Diffraction of obliquely incident Gaussian beams on waveguide gratings with infinitely long grooves is described. The analysis is based on the angular spectrum of the beam and on the grating response derived from the four-wave coupled-mode theory, which simultaneously considers all four (approximately) synchronous waves. Results concerning the shapes of the emerging beams and their directions, the power content, and the possibility of beam splitting could differ significantly from those obtained by means of two-wave coupling. The analysis method is general and can be performed on many kinds of realistic beam shapes and applications.
© 1998 Optical Society of America
Nahum Izhaky and Amos Hardy, "Oblique Incidence of Gaussian Beams on Waveguide Gratings with the Four-Wave Coupled-Mode Theory," Appl. Opt. 37, 5806-5815 (1998)