Most electromagnetic phenomena pertaining to metamaterials are observed at the resonance positions. In this review, we have collated and analyze the most prevalent forms of resonance-based phenomena observed in metamaterials to serve as a ready reference for future researchers. Our focus will be on metamaterials operating at the terahertz frequency domain. Starting with the origin and evolution of fundamental LC resonances in metamaterials, we would explain occurrence of typical even and odd higher order resonance modes. We have also discussed Fano resonances in asymmetric gap resonators-based metamaterials. Further, quantum phenomena analogues, such as, electromagnetically induced transparency (EIT) or Plasmon Induced Transparency (PIT), which can significantly influence the metamaterials resonances are also discussed. Thereafter, origins to ultra-sharp resonances in toroidal metamaterials, along with chiral metamaterials and resonance mode hybridization effects in the context of terahertz metamaterials are described. This review should be useful for undertaking.

中文翻译：

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太赫兹域电磁超材料的共振现象：综述

大多数与超材料有关的电磁现象都是在共振位置观察到的。在这篇综述中，我们整理并分析了在超材料中观察到的最普遍的基于共振的现象形式，以作为未来研究人员的现成参考。我们的重点将放在在太赫兹频域运行的超材料。从超材料中基本 LC 共振的起源和演变开始，我们将解释典型偶数和奇数高阶共振模式的发生。我们还讨论了基于非对称间隙谐振器的超材料中的 Fano 谐振。此外，还讨论了量子现象类似物，例如电磁感应透明 (EIT) 或等离子体感应透明 (PIT)，它们可以显着影响超材料共振。此后，描述了环形超材料中超尖锐共振的起源，以及太赫兹超材料背景下的手性超材料和共振模式杂化效应。这种审查应该有助于进行。