We report what are to our knowledge the first observation and characterization of quadratic spatial solitons in periodically poled lithium niobate (PPLN). Using a Nd:YAG (1064-nm) source, we observed self-trapped solitary-wave propagation over more than six diffraction lengths as a result of the cascaded quadratic nonlinear process. Low-threshold operation (5-kW peak power) was measured for the quasi-phase-matched PPLN structure designed for frequency doubling.
© 1999 Optical Society of America
(190.2620) Nonlinear optics : Harmonic generation and mixing
(190.4420) Nonlinear optics : Nonlinear optics, transverse effects in
(190.5530) Nonlinear optics : Pulse propagation and temporal solitons
B. Bourliaguet, V. Couderc, A. Barthélémy, G. W. Ross, P. G. R. Smith, D. C. Hanna, and C. De Angelis, "Observation of quadratic spatial solitons in periodically poled lithium niobate," Opt. Lett. 24, 1410-1412 (1999)