This study investigates the enhancement and nanofocusing of a radially polarized electric field by a conical plasmonic structure (CPS). The CPS is a dielectric cone with nanometer metal cladding on a dielectric substrate. Concentric circular slanted grooves are etched on the surface of the dielectric substrate. These grooves converge the incident field on the structure. Angled periodic gratings are engraved on the CPS metal surface near the tip, creating a plasmonic momentum and contributing to the field enhancement above the apex. The symmetry of the incident radially polarized light and the structure significantly boosts nanofocusing and field enhancement. The optimal width of the nanofocusing and the electric field enhancement factor obtained are approximately 9 nm and 30000, respectively. Because of its impressive effects, this scheme is a valuable tool for plasmonic, optics, and laser applications.

中文翻译：

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利用轴对称等离子体结构和凹槽来纳米聚焦和超增强径向极化电场

本研究研究了锥形等离子体结构（CPS）对径向极化电场的增强和纳米聚焦。CPS 是在介电基板上具有纳米金属包层的介电锥体。在介质基片表面刻蚀出同心圆斜槽。这些凹槽将入射场会聚在结构上。成角度的周期性光栅刻在尖端附近的 CPS 金属表面上，产生等离激元动量并有助于顶点上方的场增强。入射径向偏振光和结构的对称性显着增强了纳米聚焦和场增强。获得的最佳纳米聚焦宽度和电场增强因子分别约为9 nm和30000。由于其令人印象深刻的效果，该方案是等离子体、光学和激光应用的宝贵工具。