Wedge-shaped inclined slit long-focal-depth Plasmon lens

Abstract

The invention discloses a wedge-shaped inclined slit long-focal-depth Plasmon lens. The wedge-shaped inclined slit long-focal-depth Plasmon lens is characterized in that the wedge-shaped inclined slit long-focal-depth Plasmon lens is formed by constructing a vertical central slit with uniform width and wedge-shaped inclined slits which are bilaterally symmetrical with the central slit on a planar metal film; the lens can realize the focusing effect with long focal depth when the lens is in the vertical incidence condition of polarized light of a transverse magnetic line; in the structure, the central slit is selected as a lens symmetric axis; the wedge-shaped inclined slits appear in pairs for the central slit and are symmetrical with the central slit; the wedge-shaped inclined slits incline outwards relative to the central slit on an incidence plane end, and the slit towards outside most has a bigger inclination angle; when the slit incident end is wider than the emitting end, the symmetric slit inner wall inclination angle, outer wall inclination angle and the width are the same; and the wedge-shaped inclined slit long-focal-depth Plasmon lens realizes the focusing effect with long focal depth for the polarized light of the transverse magnetic line for the planar metal Plasmon lens. The wedge-shaped inclined slit long-focal-depth Plasmon lens is compact in structure, is convenient for preparation and production in reality, and has better application prospects in the optical micro manipulation field, the optical micro processing field and the like.

Description

technical field [0001] The invention belongs to the field of subwavelength photonics and integrated optics, in particular to a transverse magnetic linearly polarized light focusing lens based on the plasmon effect. Background technique [0002] Surface plasmon polaritons (SPPs), electromagnetic waves (EW) coupled with collective electron oscillations propagating at the interface between metals and dielectrics, have been rapidly developed in the past 10 years. Because of their excellent properties, they offer great potential to control beam propagation and modulate the distribution of light fields at the nanoscale, and have attracted extensive attention in this field. More and more plasmonic components have been proposed to achieve various functions and have shown good performance in both simulations and experiments. [0003] Surface plasmons can break through the diffraction limit and have strong local field enhancement characteristics, which can realize nanoscale optical i...

AI Technical Summary

Problems solved by technology

Hongyan Shao et al. published in the journal "Plasmonics" in 2016 entitled "Plasmonic Planar Lens Based on Slanted NanolistArray" proposed a planar metal lens structure that can achieve tight focusing of linearly polarized light, overcoming the structural difficulties of curved lenses , but there is still a lot of room for optimization in its focusing effect such as the depth of focus

Images