Multiorder nonlinear diffraction in frequency doubling processes

Nonlinear Physics Centre, CUDOS, Research School of Physics and Engineering, The Australian National University, Canberra ACT, Australia.
Optics Letters (Impact Factor: 3.29). 04/2009; 34(6):848-50. DOI: 10.1364/OL.34.000848
Source: PubMed


We analyze experimentally light scattering from chi(2) nonlinear gratings and observe two types of second-harmonic frequency-scattering processes. The first process is identified as Raman-Nath type nonlinear diffraction that is explained by applying only transverse phase-matching conditions. The angular position of this type of diffraction is defined by the ratio of the second-harmonic wavelength and the grating period. In contrast, the second type of nonlinear scattering process is explained by the longitudinal phase matching only, being insensitive to the nonlinear grating period.

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