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arXiv · 1012.1351

First-Principle Homogenization Theory for Periodic Metamaterials

Andrea Alu
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Abstract

We derive from first principles an accurate homogenized description of periodic metamaterials made of magnetodielectric inclusions, highlighting and overcoming relevant limitations of standard homogenization methods. We obtain closed-form expressions for the effective constitutive parameters, pointing out the relevance of inherent spatial dispersion effects, present even in the long-wavelength limit. Our results clarify the limitations of quasi-static homogenization models, restore the physical meaning of homogenized metamaterial parameters and outline the reasons behind magnetoelectric coupling effects that may arise also in the case of center-symmetric inclusions.

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Andrea Alu. 2010-12-06. First-Principle Homogenization Theory for Periodic Metamaterials. https://doi.org/10.1103/physrevb.84.075153

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