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arXiv · 2102.13305

Temporal Brewster angle

Victor Pacheco-Peña·Nader Engheta
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Abstract

Controlling amplitude, phase and polarization of electromagnetic waves is key for a full manipulation of wave-matter interactions. The Brewster angle is one of the important features in this context. Here, we exploit metamaterial concepts with a time-modulated permittivity to propose the temporal equivalent of the spatial Brewster angle, a concept we call temporal Brewster angle. We consider temporal boundaries (as the temporal equivalent of the spatial boundaries between two media) by rapidly changing the permittivity of the medium, where a wave travels, from isotropic to an anisotropic permittivity tensor. It is theoretically shown that when the incidence angle coincides with that of the temporal Brewster angle a forward (temporal transmission) wave is produced while the backward (temporal reflection) is eliminated. We provide a closed-form analytical expression of the temporal Brewster angle and demonstrate its performance both theoretically and numerically. Our findings may provide a fresh view on how to control electromagnetic wave propagation and wave-matter interactions in real time using temporal metamaterials.

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Victor Pacheco-Peña, Nader Engheta. 2021-02-26. Temporal Brewster angle. https://doi.org/10.1103/physrevb.104.214308

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