title: Shaping of light beams by 3D direct laser writing on facets of nonlinear crystals.
abstract: We demonstrate experimentally spatial-mode conversions of light beams generated in a quadratic nonlinear process by micron-scale structures placed on the facets of nonlinear crystals. These structures were printed on the crystal facets using a three-dimensional (3D) direct laser writing system. The functional structures were designed to modify the phase of the beam at specific wavelengths, thereby enabling conversion of a fundamental Gaussian laser beam into different high-order Hermite-Gaussian modes, Laguerre-Gaussian modes, and zeroth-order Bessel beams of the second harmonic. This facet functionalization opens exciting new opportunities for robust and compact beam shaping in a nonlinear interaction without compromising the conversion efficiency.
authors.forename: Shlomi
authors.initials: S
authors.lastname: Lightman
authors.forename: Raz
authors.initials: R
authors.lastname: Gvishi
authors.forename: Gilad
authors.initials: G
authors.lastname: Hurvitz
authors.forename: Ady
authors.initials: A
authors.lastname: Arie