Prism coupling into second-order nonlinear waveguides

M. G. Masi, and G. Assanto

Opt. Commun. 146, 95-98 (1998)


We numerically investigate the effects of second-harmonic generation in the coupling of an external laser beam into a thin-film waveguide in the presence of a quadratic susceptibility c(2). A nonlinear phase shift through a cascading mechanism affects the in-coupling of a fundamental frequency beam, modifying the effective detuning. Conversely, such nonlinear behaviour can be exploited for in situ evaluation of the waveguide quadratic characteristics.