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arXiv · 2108.05178

Ultra-wideband Antireflection Assisted by Continuously Varying Temporal Medium

Yi Zhang·Liang Peng·Zhengjie Huang·Lixin Ran·Dexin Ye
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Abstract

We demonstrate that reflectionless propagation of electromagnetic waves between two different materials can be achieved by designing an intermediate temporal medium, which can work in an ultra-wide frequency band. Such a temporal medium is designed with consideration of a multi-stage variation of the material' s permittivity in the time domain. The multi-stage temporal permittivity is formed by a cascaded quarter-wave temporal coating, which is an extension of the antireflection temporal coating by Pacheco-Pe\~na et al [[1] Optica 7, 323 (2020)]. The strategy to render ultra-wideband antireflection temporal medium is discussed analytically and verified numerically. In-depth analysis shows that the multi-stage design of the temporal media implies a continuously temporal variation of the material' s constitutive parameters, thus an ultra-wideband antireflection temporal medium is reasonably obtained. As an illustrative example for application, the proposed temporal medium is adopted to realize impedance matching between a dielectric slab and free space, which validates our new findings.

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Yi Zhang, Liang Peng, Zhengjie Huang, Lixin Ran, Dexin Ye. 2021-08-11. Ultra-wideband Antireflection Assisted by Continuously Varying Temporal Medium. https://arxiv.org/abs/2108.05178

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