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arXiv · 1012.1353

Restoring the Physical Meaning of Metamaterial Constitutive Parameters

Andrea Alu
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Abstract

Metamaterial homogenization is often based on implicit assumptions inspired to natural material models. Retrieved effective permittivity and permeability, however, are often non-physical, especially near the array resonances, of most interest for metamaterial applications. We explain here the nature of typical homogenization artifacts, relating them to an inherent form of magneto-electric coupling associated with the finite phase velocity along metamaterial arrays. Our findings allow restoring the proper definition and physical meaning of local constitutive parameters for metamaterials.

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Andrea Alu. 2010-12-06. Restoring the Physical Meaning of Metamaterial Constitutive Parameters. https://doi.org/10.1103/physrevb.83.081102

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