Metallo-dielectric structured materials, or in other words metamaterials (MTM), are in principle a well established
composite to improve efficiency, functionality, and weight of micro-wave components. In recent times, it has been
demonstrated that the functionalities of metamaterials can be scaled down to optical frequencies by nano structuring
techniques. Examples include negative index materials in the near infrared and visible frequency range, cloaking
structures, filters, and structures for improved sensing of environmental gases.
The physical processes in plasmonic metamaterials depend strongly on the excitation of surface plasmons and the
interaction between them.
We have learned how to control the plasmon-photon and the plasmon-plasmon interaction for manipulating the
electromagnetic response in a metamaterial at wavelengths well below the vacuum wavelength. Many interesting
and novel optical applications and devices are expected. For instance sub-wavelength imaging, compact
communication devices as polarisation splitters, slow light media structures, compact colour filters, and resonators.
All-plasmonic circuits are also the basis for ultra-dense photonic integration not achievable through the conventional
optical integration.
With examples of several metamaterial structures we try to illustrate the application potential of MTMs and
comment on their fabrication feasibility to show whether metamaterials can hold their promise. Their investigation is
in any case a rewarding adventure.
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