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arXiv · 1610.08704

Negative refractive index induced by percolation in disordered metamaterials

Brian A Slovick
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Abstract

An effective medium model is developed for disordered metamaterials containing a spatially random distribution of dielectric spheres. Similar to effective medium models for ordered metamaterials, this model predicts resonances in the effective permeability and permittivity arising from electric- and magnetic-dipole Mie resonances in the spheres. In addition, the model predicts a redshift of the electric resonance with increasing particle loading. Interestingly, when the particle loading exceeds the percolation threshold of 33\%, the model predicts that the electric resonance overlaps with the magnetic resonance, resulting in a negative refractive index.

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Brian A Slovick. 2017-03-08. Negative refractive index induced by percolation in disordered metamaterials. https://doi.org/10.1103/physrevb.95.094202

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