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Dispersive 2D Cherenkov radiation on a dielectric nano-film.

ABSTRACT: We report a modified two-dimensional Cherenkov radiation, which occurs on a high-index dielectric nano-film driven by uniformly moving electron-beam. It is essentially different from the ordinary Cherenkov radiation in that, in the nondispersive medium, it shows unique dispersion characteristics-the waves with higher frequencies radiate at larger Cherenkov angles. Its radiation frequency and direction are essentially determined by structure parameters as well as the beam-velocity. By means of fully electromagnetic simulations and theoretical analyses, we explored the mechanism and requirements of this radiation. This new Cherenkov radiation may lead to promising applications in a broad range of fields.

SUBMITTER: Liu W

PROVIDER: S-EPMC5517661 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Dispersive 2D Cherenkov radiation on a dielectric nano-film.

Liu Weihao W

Scientific reports 20170719 1

We report a modified two-dimensional Cherenkov radiation, which occurs on a high-index dielectric nano-film driven by uniformly moving electron-beam. It is essentially different from the ordinary Cherenkov radiation in that, in the nondispersive medium, it shows unique dispersion characteristics-the waves with higher frequencies radiate at larger Cherenkov angles. Its radiation frequency and direction are essentially determined by structure parameters as well as the beam-velocity. By means of fu ...[more]

PMID: 28724940

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