Transition metamaterials with spatially separated zeros

The State University of New York at Buffalo, Buffalo, New York 14260, USA.
Optics Letters (Impact Factor: 3.29). 09/2011; 36(18):3624-6. DOI: 10.1364/OL.36.003624
Source: PubMed


We report analytical and numerical studies of the effect of the separation distance between zeros of dielectric permittivity and magnetic permeability on the phenomena of resonant absorption and anomalous field enhancement in transition metamaterials. Our studies indicate that these phenomena are robust and strongly polarization-dependent in the presence of the spatial shift between these points. These results are likely to be important for future fundamental and applied studies in the areas of transformation, polarization, and nonlinear optics in metamaterials.

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    ABSTRACT: We theoretically and numerically investigate the phenomenon of resonant field enhancement of Gaussian beams in two types of transition metamaterials: with a positive-zero-negative index profile and with a positive-zero-positive index profile and demonstrate strongly localized resonant field enhancement in both cases. This study is likely to have applications in the fields of nano-optics, sub-wavelength imaging, and nano-fabrication and lays a foundation for the studies of more complex vector and vortex beam propagation in graded-index metamaterials.
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    Scientific Reports 10/2013; 3:2954. DOI:10.1038/srep02954 · 5.58 Impact Factor
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