We carried out second-harmonic generation in quasi-phase-matched α-phase lithium niobate channel waveguides realized by proton exchange and surface periodic poling. Owing to a limited ferroelectric domain depth, we could observe the interplay between second-harmonic generation and self-phase modulation due to cascading and cubic effects, resulting in a nonlinear resonance shift. Data reduction allowed us to evaluate both the quadratic nonlinearity in the near infrared as well as the depth of the uninverted domains.
© 2007 Optical Society of America
Original Manuscript: January 16, 2007
Revised Manuscript: March 22, 2007
Manuscript Accepted: March 22, 2007
Published: June 15, 2007
S. Stivala, A. Pasquazi, L. Colace, G. Assanto, A. C. Busacca, M. Cherchi, S. Riva-Sanseverino, A. C. Cino, and A. Parisi, "Guided-wave frequency doubling in surface periodically poled lithium niobate: competing effects," J. Opt. Soc. Am. B 24, 1564-1570 (2007)