Beam shaping using genetically optimized two-dimensional photonic crystals.

J Opt Soc Am A Opt Image Sci Vis

Département de physique, de génie physique et d’optique, Faculté des Sciences et de Génie, Université Laval, Québec G1V 0A6, Canada.

Published: December 2012

We propose the use of two-dimensional (2D) photonic crystals (PhCs) with engineered defects for the generation of an arbitrary-profile beam from a focused input beam. The cylindrical harmonics expansion of complex-source beams is derived and used to compute the scattered wave function of a 2D PhC via the multiple scattering method. The beam shaping problem is then solved using a genetic algorithm. We illustrate our procedure by generating different orders of Hermite-Gauss profiles, while maintaining reasonable losses and tolerance to variations in the input beam and the slab refractive index.

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http://dx.doi.org/10.1364/JOSAA.29.002673DOI Listing

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