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arXiv · 1804.07358

Theory of electromagnetic wave frequency upconversion in dynamic media

Kenan Qu·Qing Jia·Matthew R. Edwards·Nathaniel J. Fisch
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Abstract

Frequency upconversion of an electromagnetic wave can occur in ionized plasma with decreasing electric permittivity and in split-ring resonator-structure metamaterials with decreasing magnetic permeability. We develop a general theory to describe the evolution of the wave frequency, amplitude, and energy density in homogeneous media with a temporally decreasing refractive index. We find that upconversion of the wave frequency is necessarily accompanied by partitioning of the wave energy into low-frequency modes, which sets an upper limit on the energy conversion efficiency. The efficiency limits are obtained for both varying permittivity and varying permeability.

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BibTeXRIS

Kenan Qu, Qing Jia, Matthew R. Edwards, Nathaniel J. Fisch. 2018-04-19. Theory of electromagnetic wave frequency upconversion in dynamic media. https://doi.org/10.1103/physreve.98.023202

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