Experiments observation of engineering photonic jet array by core-shell phase diffraction grating

摘要

In this Letter, we investigated the experimental observation of the specific spatially localized photonic jet array formed by core-shell phase diffraction gratings (PDGs). The core-shell PDG consists of a metallic shell (copper, silver, and gold) and a dielectric core (polydimethylsiloxane) with the hemispherical and triangular grooves. The finite-difference time-domain technique is employed to simulate the near-field scattering of optical radiation at different core-shell PDGs. The direct imaging of a photonic jet array is performed by a scanning optical microscope for experimental verification. Our numerical and experimental results showed that each type of core-shell PDGs generate the photonic jet array with unique properties. The optical intensity of the photonic jet array is greatly enhanced by gold-coating PDG due to surface plasmon resonance. The presented core-shell PDGs can be manipulated to design high-efficiency optical elements for steering the photonic jet array in a wide range of applications. (C) 2020 Optical Society of America