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arXiv · 2306.12808

The theory of electromagnetic line waves

S. A. R. Horsley·A. Dwivedi
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Abstract

Whereas electromagnetic surface waves are confined to a planar interface between two media, line waves exist at the one-dimensional interface between three materials. Here we derive a non-local integral equation for computing the properties of line waves, valid for surfaces characterised in terms of a general tensorial impedance. We find a good approximation -- in many cases -- is to approximate this as a local differential equation, where line waves are one-dimensional analogues of surface plasmons bound to a spatially dispersive metal. For anisotropic surfaces we find the oscillating decay of recently discovered `ghost' line waves can be explained in terms of an effective gauge field induced by the surface anisotropy. These findings are validated using finite element simulations.

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S. A. R. Horsley, A. Dwivedi. 2023-06-22. The theory of electromagnetic line waves. https://arxiv.org/abs/2306.12808

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