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Ultra-wideband Antireflection Temporal Medium

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 نشر من قبل Yi Zhang
 تاريخ النشر 2021
  مجال البحث فيزياء
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We show that it is possible to achieve a perfect impedance matching by designing an antireflection temporal medium, which is omnidirectional and frequency-independent in an ultra-wide band. Our approach is an extension of the antireflection temporal coating by Pacheco-Pe~na et al [Optica 7, 323 (2020)]. We demonstrate that a specially-engineered multi-stage discrete or continuous temporal changing in the permittivity of the temporal medium allows ultra-wideband reflectionless wave propagation, which has been confirmed analytically and numerically. As an illustrative example for application, the proposed approach is applied to match a dielectric slab with free space for an ultra-wideband pulse.



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