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arXiv · 1411.7779

Anisotropic Metamaterial Optical Fibers

Dheeraj Pratap·S. Anantha Ramakrishna·Justin G. Pollock·Ashwin K. Iyer
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Abstract

Internal physical structure can drastically modify the properties of waveguides: photonic crystal fibers are able to confine light inside a hollow air core by Bragg scattering from a periodic array of holes, while metamaterial loaded waveguides for microwaves can support propagation at frequencies well below cutoff. Anisotropic metamaterials assembled into cylindrically symmetric geometries constitute light-guiding structures that support new kinds of exotic modes. A microtube of anodized nanoporous alumina, with nanopores radially emanating from the inner wall to the outer surface, is a manifestation of such an anisotropic metamaterial optical fiber. The nanopores, when filled with a plasmonic metal such as silver or gold, greatly increase the electromagnetic anisotropy. The modal solutions in anisotropic circular waveguides can be uncommon Bessel functions with imaginary orders.

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Dheeraj Pratap, S. Anantha Ramakrishna, Justin G. Pollock, Ashwin K. Iyer. 2014-11-28. Anisotropic Metamaterial Optical Fibers. https://doi.org/10.1364/oe.23.009074

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