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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
Herpin equivalence in temporal metamaterials
Giuseppe Castaldi1, Massimo Moccia1, Nader Engheta2
1Department of Engineering, Fields & Waves Lab, University of Sannio, Benevento, I-82100, Italy.
Abstract:
In analogy with spatial multilayers, we put forward the idea of Herpin equivalence in temporal metamaterials characterized by step-like time variations of the constitutive parameters. We show that, at a given frequency, an arbitrary temporal multistep exhibiting mirror symmetry can be replaced by an equivalent temporal slab with suitable refractive index and travel-time. This enables the synthesis of arbitrary values of the refractive index, in a way that differs fundamentally from the effective-medium approach, and adds new useful analytical machinery to the available toolbox for the study and design of temporal metamaterials, with potentially intriguing applications to anti-reflection coatings and filters.
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