We demonstrate control of the nonlinear conversion across a beam profile by using periodically poled lithium niobate with a laterally nonuniform quasi-phase-matching grating. As a representative experiment, generation of a flat-top second-harmonic beam is demonstrated.
© 1998 Optical Society of America
(050.2770) Diffraction and gratings : Gratings
(140.0140) Lasers and laser optics : Lasers and laser optics
(160.3730) Materials : Lithium niobate
(190.2620) Nonlinear optics : Harmonic generation and mixing
G. Imeshev, M. Proctor, and M. M. Fejer, "Lateral patterning of nonlinear frequency conversion with transversely varying quasi-phase-matching gratings," Opt. Lett. 23, 673-675 (1998)