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arXiv · 1710.01625

New Electromagnetic Modes in Space-Time Modulated Dispersion-Engineered Media

Nima Chamanara·Zoé-Lise Deck-Léger·Christophe Caloz·Dikshitulu Kalluri
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Abstract

We report on new electromagnetic modes in space-time modulated dispersion-engineered media. These modes exhibit unusual dispersion relation, field profile and scattering properties. They are generated by coupled codirectional space-time harmonic pairs, and occur in space-time periodic media whose constituent materials exhibit specific dispersion. Excitation of a slab of such a medium with subluminal modulation results in periodic transfer of energy between the incident frequency and a frequency shifted by a multiple of the modulation frequency, whereas superluminal modulation generates exponentially growing frequencies. These modes may find applications in optical mixers, terahertz sources and other optical devices.

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Nima Chamanara, Zoé-Lise Deck-Léger, Christophe Caloz, Dikshitulu Kalluri. 2017-10-04. New Electromagnetic Modes in Space-Time Modulated Dispersion-Engineered Media. https://doi.org/10.1103/physreva.97.063829

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