Helical light emission from plasmonic vortices via magnetic tapered tip

N Maccaferri,D Garoli,Y Gorodetski

doi:10.1088/1742-6596/961/1/012001

N Maccaferri, D Garoli + Show 1 more

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https://doi.org/10.1088/1742-6596/961/1/012001

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Abstract

We investigate an architecture where a plasmonic vortex excited in a gold surface propagates on an adiabatically tapered magnetic tip and detaches to the far-field while carrying a well-defined optical angular momentum. We analyze the out-coming light and show that, despite generally high losses of flat magnetic surface, our 3D structure exhibits high energy throughput. Moreover, we show that once a magneto-optical activity is activated inside the magnetic tip a modulation of the total power transmittance is possible.

Highlights

Structured optical beams became a subject of an intense research [1], due to numerous potential applications they offer in the fields of super-resolution imaging [2], optical tweezing [3], nanomanipulation [4] and telecommunications [5]
We investigate an architecture where a plasmonic vortex excited in a gold surface propagates on an adiabatically tapered magnetic tip and detaches to the far-field while carrying a welldefined optical angular momentum
plasmonic vortices (PVs) are usually generated by coupling propagating vortex beams to the plasmonic mode on a metal surface by using center-symmetric coupling structure, known as plasmonic vortex lenses (PVLs) [9]

Summary

Introduction

Structured optical beams became a subject of an intense research [1], due to numerous potential applications they offer in the fields of super-resolution imaging [2], optical tweezing [3], nanomanipulation [4] and telecommunications [5]. A special interest is dedicated to investigation of the interaction of structured light with metallic nanostructures, resulting in Surface Plasmon Polaritons (SPPs) carrying angular momentum (AM) [6,7,8,9,10,11,12,13] These surface confined electromagnetic distributions are generally defined by a field singularity surrounded by a helical phase front, referred here as plasmonic vortices (PVs). These effects can be solely controlled by the properly designed 3D shape of the tip and by the illuminating beam parameters.

Published under licence by IOP Publishing Ltd

Findings

Conclusions