We report on the measurement of nonlinear phase shift phiv NL induced by a strong pump at wavelength lambda_p on a weak signal at lambda_s through a cascade of two second-order interactions in a periodically poled lithium-niobate waveguide. The experiment is performed by use of an interferometric scheme especially designed to be insensitive to slow mechanical and thermal drift effects. The observed behavior of phiv NL as a function of pump power and of wavelength difference lambda_p − lambda_s is in good agreement with the theoretical predictions.
© 2005 Optical Society of America
(130.2790) Integrated optics : Guided waves
(130.3730) Integrated optics : Lithium niobate
(190.2620) Nonlinear optics : Harmonic generation and mixing
(190.4390) Nonlinear optics : Nonlinear optics, integrated optics
Carlo Liberale, Vittorio Degiorgio, Marco Marangoni, Gianluca Galzerano, and Roberta Ramponi, "Measurement of the nonlinear phase shift induced by cascaded interactions in a periodically poled lithium niobate waveguide," Opt. Lett. 30, 2448-2450 (2005)