Curved space plasmonic optical elements.

We have designed and experimentally studied non-planar curved space plasmonic optical elements. Three different smooth curved space plasmonic structures were studied: a dome that acts either as a focusing element or as a deflector for plasmonic beams, a cone that acts as a plasmonic prism, and a tapered book cover that alters the size of a plasmonic guided wave. The functional mechanism of these elements relies purely on the curvature-induced effective potential and does not require any additional dielectric layer for shaping the plasmonic beams.

Dynamic control of light beams in second harmonic generation.

In this Letter, we report the dynamic control of the spatial shape of the second harmonic (SH) beam generated in a nonlinear crystal, by controlling the phase of the input fundamental beam before entering the crystal. This method enables 2D beam shaping and does not require any special fabrication beforehand. We have shown in simulation and experiment that this is possible for both short and long crystals: for short crystals, we assume the transverse phase of the SH beam is doubled relative to the input phase of the fundamental beam; for longer crystals, genetic algorithms were used in order to solve the inverse phase problem, which generally does not have an analytical solution.

Nonlinear diffraction from high-order Hermite-Gauss beams.

We investigate experimentally and theoretically the nonlinearly diffracted second harmonic light from the first-order Hermite-Gauss beam. We investigate the cases of loosely and tightly focused beams in a periodically poled lithium niobate crystal in the temperature range near the birefringent phase matching. Unlike the case of fundamental Gaussian beam, the nonlinear diffracted beam is spatially structured.

Rapidly accelerating Mathieu and Weber surface plasmon beams.

We report the generation of two types of self-accelerating surface plasmon beams which are solutions of the nonparaxial Helmholtz equation in two dimensions. These beams preserve their shape while propagating along either elliptic (Mathieu beam) or parabolic (Weber beam) trajectories. We show that owing to the nonparaxial nature of the Weber beam, it maintains its shape over a much larger distance along the parabolic trajectory, with respect to the corresponding solution of the paraxial equation-the Airy beam.