A comparative study of semiconductor-based plasmonic metamaterials. (arXiv:1108.1531v1 [physics.optics])

A comparative study of semiconductor-based plasmonic metamaterials. (arXiv:1108.1531v1 [physics.optics]): "
Recent metamaterial (MM) research faces several problems when using
metal-based plasmonic components as building blocks for MMs. The use of
conventional metals for MMs is limited by several factors: metals such as gold
and silver have high losses in the visible and near-infrared (NIR) ranges and
very large negative real permittivity values, and in addition, their optical
properties cannot be tuned. These issues that put severe constraints on the
device applications of MMs could be overcome if semiconductors are used as
plasmonic materials instead of metals. Heavily doped, wide bandgap oxide
semiconductors could exhibit both a small negative real permittivity and
relatively small losses in the NIR. Heavily doped oxides of zinc and indium
were already reported to be good, low loss alternatives to metals in the NIR
range. Here, we consider these transparent conducting oxides (TCOs) as
alternative plasmonic materials for many specific applications ranging from
surface-plasmon-polariton waveguides to MMs with hyperbolic dispersion and
epsilon-near-zero (ENZ) materials. We show that TCOs outperform conventional
metals for ENZ and other MM-applications in the NIR.

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