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arXiv · 1512.04285

Focused electromagnetic doughnut pulses and their interaction with interfaces and nanostructures

T. A. Raybould·V. A. Fedotov·N. Papasimakis·I. J. Youngs·N. I. Zheludev
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Abstract

We study the propagation properties and light-matter interactions of the focused doughnut pulses, broadband, single-cycle electromagnetic perturbations of toroidal topology first described by Hellwarth and Nouchi in 1996. We show how focused doughnuts are reflected and refracted at planar metallic and vacuum-dielectric interfaces leading to complex distortions of the field structure. We also identify the conditions under which these toroidal pulses excite dominant dynamic toroidal dipoles in spherical dielectric particles.

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T. A. Raybould, V. A. Fedotov, N. Papasimakis, I. J. Youngs, N. I. Zheludev. 2015-12-14. Focused electromagnetic doughnut pulses and their interaction with interfaces and nanostructures. https://doi.org/10.1364/oe.24.003150

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