Finite-size nondiffracting beam from a subwavelength metallic hole with concentric dielectric gratings

摘要

We show that finite-size nondiffracting beams can be generated by a subwavelength metallic hole with surrounding dielectric grating structures. An analytic field model that describes the diffractive formation of finite-size nondiffracting beams is addressed. The generation of finite-size nondiffracting beams from a subwavelength metallic hole with surrounding concentric dielectric binary gratings is numerically demonstrated by three-dimensional rigorous coupled wave analysis.