In a study concerned with second-harmonic generation at grating couplers, Kull et al. [Opt. Lett. 16, 1930 (1991)] observed a curious phenomenon in which the second-harmonic efficiency exhibits dips, instead of peaks, when the angle of incidence of the pump beam is scanned through its resonant value. This surprising result has not been explained. It is our aim to show that this effect is closely related to the existence of nonlinear zeros.
© 1995 Optical Society of America
R. Reinisch, J. L. Coutaz, J. F. Roux, E. Popov, and M. Nevière, "Nonlinear zeros in second-harmonic generation at grating couplers," Opt. Lett. 20, 347-349 (1995)